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Transcript
Dalhousie Heat Flow Probe Hardware Reference Manual Doc:ument #:1626 Version 1.0 January 10, 2000 I I I I I Prepared by: AMIRD< Systems Inc. 77 Chain Lake Drive Halifax, Nova Scotia B3S lEI Prepared for: Department of Oceanography Dalhousie University Halifax, Nova Scotia B3H 4Jl ~ Approved: ~~(1 ~'I Project Manager -Brett Eskritt AM~ i I I I @ (2000) Dalhousie University. All rights reserved. The information contained herein includes information which is confidential and proprietary to Dalhousie University and may not be used or disclosed without prior written consent of Dalhousie University. I I I I I I ii Revision Date Description of Revision 1.0 January 10, 2000 Initial release . I I I I I I I I I I I I iii Table of Contents 1. Introduction 2. Hardware Users Manual 2 2.1 Lower Board External Connections 2 2.1.1 Tilt Sensor Inputs 3 2.1.2 Thermistor Connections 4 2.1.3 Bridge Resistors 5 2.1.4 Lower Multiplexor Controls 6 2.1.5 Jog Detector Inputs 7 2.2 Upper Board External Connections 7 2.2.1 Heater Power Supply 8 2.2.2 Pinger Power Supply 9 2.2.3 Pinger Connection 9 2.2.4 Isolated RS-232 10 2.2.5 Electronics Power Supply 10 2.2.6 Heater Connection 11 2.3 Lower Board Jumper Settings 11 2.3.1 Analog to Digital Converter Microcontroller Programming Jumpers 12 2.3.2 Audible Jog Detector Indicator 13 2.4 Upper Board Jumper Settings 13 2.4.1 Pinger Microcontroller Programming Jumpers 14 2.4.2 Pinger Frequency Select Jumpers 14 3. Hardware Reference 3.1 Introduction 15 I 3.2 Thermistor Analog to Digital Conversion -Lower Board 15 3.2.1 Slew Rate Limiting of Amplifiers 15 3.2.2 Offset Resistor Settings 17 3.2.3 Gain Resistor Settings 18 3.2.4 Balance Adjust 18 3.3 Voltage and Current Monitors -Upper Board 18 3.3.1 Heat Pulse Voltage Monitor 18 3.3.2 Heat Pulse Current Monitor 19 3.3.3 Heat Pulse Battery Pack Monitor 19 3.3.4 Pinger Battery Pack Monitor 20 3.3.5 Electronics Battery Pack 20 3.3.6 Isolated Grounds 20 I 4. Assembly Instructions 4.1 Upper Board Assembly 22 4.2 Upper Board ECO List 26 4.3 Upper Board Notes ; 28 I iv 4.4 Lower Board Assembly 28 4.5 Lower Board ECD List 31 4.6 Lower Board Notes ""." ' '."'.' '..' 32 Appendix A: Lower Board Original Schematics 33 Appendix B: Lower Board Revised Schematics 38 Appendix C: Upper Board Original Schematics 43 Appendix D: Upper Board Revised Schematics , Appendix E: Lower Board Bill of Materials 57 Appendix F: Upper Board Bill of Materials 60 Appendix G: Lower Board Assembly Drawings 64 Appendix H: Upper Board Assembly Drawings 67 Appendix I: Lower Board Mechanical Drawing 70 Appendix J: Upper Board Mechanical Drawing 72 I I I I I I I I , 50 I v List of Tables Table 2-1: Lower Board External Connector Description 2 Table 2-2: Tilt Sensor Signal Description "'.' ""."""""""'..."""""""""" 3 Table 2-3: Thermistor Signal Description ".".."."""."."'...'.' """"""'.'." 5 Table 2-4: Bridge Resistor Connections 6 Table 2-5: Reference Resistor Connections 6 Table 2-6: Lower MUX Control Signals 7 Table 2-7: Jog Detector Signal Description 7 Table 2-8: Upper Board External Connector Description 8 Table 29: Heater Power Supply , 9 Table 2-10: Pinger Power Supply ".."'.'.'."".""'.""'.'.."""""""".'...' 9 Table 2-11: Pinger Connection "." """ """""'."""." 9 Table 2-12: Serial Connections for PC DTE """""."".""""""""'.""""" 10 Table 213: Isolated RS-232 Signals 10 Table 2-14: Electronics Battery Pack '.""".".""""'..""."""""""""."""""" 10 Table 215: Heat Pulse Connection 11 Table 2-16: 2-Pin Jumpers Associated with Programming the ADC Microcontroller .'..' ' """"'..' 12 Table 2-17: 3-Pin Jumpers Associated with Programming the ADC Microcontroller 13 Table 2-18: Audible Jog Detector Indicator 13 Table 2-19: 2-PinJumpers Associated with Programming the Pinger Microcontroller 14 Table 2-20: 3-Pin Jumpers Associated with Programming the Pinger Microcontroller 14 Table 2-21: Pinger Frequency Selection 14 Table 3-1: Input Range versus Offset Setting 18 Figure 1-1: Heat Flow Probe Board Stack 1 Figure 2-1: Lower Board External Connector Location 2 Figure 2-2: Configuration of Combination Thermistor/Reference Channels 4 Figure 2-3: Upper Board External Connector Location 8 Figure 2-4: Lower Board Jumper Location 11 Figure 2-5: Upper Board Jumper Location , 13 Figure 3-1: Thermistor Analog Section 15 Figure 3-2: Effect of Amplifier Slew Rate Limiting , 16 Figure 3-3: Nonlinearity Error 17 I I I I A:M~ I DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 January 10, 2000 1 1. Introduction The Heat Flow Probe (HFP) was developed by AMIRIX Systems for the Department of Oceanography at Dalhousie University. The HFP was based on a previous design developed at the Department of Oceanography. The previous HFPs were lost at sea. The new design was reconstructed from the documentation available. The HFP consists of a 4-board stack as shown in Figure 1-1. Two of the boards were manufactured by AMIRD< Systems and two of the boards were purchased from third parties. The Tattletale Module was purchased from Onset Computer Corporation. The Tattletale FLASH Module was purchased from Peripheral Issues. The two boards developed by AMIRIX Systems are referred to as the Upper Board and the Lower Board. The Lower Board contains all of the high precision analog circuitry associated with the thermistors. The Upper Board contains all of the power electronics. Figure 1-1: Heat Flow Probe Board Stack I I This document includes a Hardware Users Manual, a Hardware Reference, and Assembly Instructions for the two boards. The Hardware Users Manual discusses all of the external connectors and the jumpers. This section should aid the user in assembling the completed unit. The Hardware Reference highlights the changes in the Hardware from the Conceptual Design Document (DN1518). The Conceptual Design Document contains the majority of the detailed design information. The Assembly Instructions contain the information required to build additional units. The Appendices include the schematics, the assembly drawings and the bill of materials that would be required to build additional units. I I I .llMI~ January 10, 2000 DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 2 2. Hardware Users Manual 2.1 Lower Board External Connections The connectors on the lower board are shown in Figure 2-1. ~ /11..Jl 1~I 'f..J5 I ~-- ..Jl. "..J5 / ( "" / \ I \ \ TPll 0 I TP2 0 TPl / 0 \. ""'" " I TPB 0 \\ 0 0 TP1't \ TP12 TP10 0 TP13 TP9 0 0 / / / .--/ " "'- "'""--'- 0[=~~~ J~ Figure 2-1: Lower Board External Connector Location The function of each of the connectors is shown in Table 2-1. A detailed description of each of the connectors is presented in the following sections. I Table 2-1: Lower Board External Connector Description I 2.1.1 Tilt Sensor Inputs The pinout of the tilt sensor connector (lower board -J1) is shown in Table 2-2. This interface connects to two tilt cells such as the Accustar Electronic Clinometer with a ratiometric output. The lower board supplies a +5 volt reference and a ground signal. The sensors output a voltage that is a fraction of the +5 volts supplied to it. The ratio of the output voltage to the reference voltage is proportional to the angle of inclination. At an inclination of 0 degrees the tilt cells output a voltage of 2.5 volts. The tilt cells output a voltage of 3.5 volts at an angle of +60 degrees and 1.5 volts at an angle of -60 degrees. This translates to a gain of 16.67 m V / degree. The equation describing the voltage at the input of the board with a 5-volt reference is shown below. V,ill_inpU, = 0.01667 * Angle + 2.5 (volts/ degree) Equation 1 The voltages are buffered by non-inverting buffers before being sampled by the analog to digital converters on the Tattletale. The X-axis and Y-axis non-inverting buffers have a gain of 1.169 V IV. Therefore the nominal gain from sensor to Tattletale input is 19.4833 m V I degree. The equation describing the voltage at the input of the analog to digital converter is shown below. .I I I I Vtilt_atod = 0.0194833 * Angle + 2.9225 (volts/degree) Table 2-2: Tilt Sensor Signal Description I I A:M~ Equation 2 I DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 January 10, 2000 4 2.1.2 Thermistor Connections The pinout of the thermistor connector (lower board -15) is shown in Table 2-3. This connector is where the thermistor elements are connected. There are 9 regular thermistor channels and 4 combination thermistor/reference channels. To use the regular thermistor channels a thermistor element should be connected between one of the thermistor pins (J5 -pins 1 to 9) and the feedback voltage (J5 -Pin 14). As an example thermistor 1 should be connected between pin 1 and pin 14, thermistor 2 between pin 2 and pin 14 up to thermistor 9 which is between pin 9 and pin 14. To use the combination thermistor/reference channels as thermistors resistors R42, R43, R44, R45 should be removed. Four additional thermistors can then be attached between the thermistor pins (J5 -pins 10 to 13) and the feedback voltage (J5 -Pin 14). To use the combination thermistor/reference channels as reference channels R42, R43, R44, R45 would be populated forming the lower half of the resistive divider. Both configurations are illustrated in Figure 2-2. I I v.. REFERENCE CONRGURATION V- --;jJJ IJ248 bJ5 Ptn 10 ~,~PW111 J5P.,12 J5 Pin R42 J5 PIn '4 Voe Figure 2-2: Configuration of Combination Thermistor/Reference Channels I DN: 1626 -Dalhousie Hea't Flow Probe Hardware Reference Manual V1.0 Reference Designator and Pin Number JS-Pin I JS-Pin2 JS-Pin3 )SPin4 I 1 IS- PinS Js Pin 6 JS Pin 7 JS Pin 8 JSPin9 rs -Pin 10 rs -Pin 11 fS Pin 12 fS - I I Pin 13 rSPin14 January 10, 2000 5 Description Signal Direction with ReSDect to Instrument Input ~ Input Input Input Input Input Input ~ Input Input Input Input Output Thermistor 1 Thermistor 2 Thermistor 3 Thermistor 4 Thermistor 5 Thermistor 6 Thermistor 7 Thermistor 8 Thermistor 9 Thermistor la/Reference 4 Thermistor II/Reference 5(-<{ /rJu I Thermis~/Reference 6 f... k "lJ Thermistor 13/Refer~~~,,;<.. k, Feedback V oltage (V~l Table 2-3: Thermistor Signal Description 2.1.3 Bridge Resistors One arm of the resistor bridge is formed with a thermistor (connected to JS) and a bridge resistor (connected between J20 to J21 or J22 to J24). The bridge resistors (referred to as Rbr) are intended to be easily changeable so that a different set of bridge resistors can be used for every thermistor string. The resistors should be soldered to the forked terminal blocks which mate to the connectors (120 to J21 or J22 to J24). The connections required to complete the resistive bridge are shown in Table 2-4. ~ I I I I I January 10, 2000 DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 6 I Table 2-4: Bridge Resistor Connections The reference resistive dividers are also populated using the same forked terminal and DIP socket combination. For the reference resistive dividers a fixed resistor is used instead of a thermistor. A bridge resistor is also required to complete that arm of the bridge. Reference Resistor Refl Ref2 Ref3 Header Connection J22F to J24F J22G to J24G J22H toT24H Bridge Resistor Rbr14 Rbr15 Rbr16 Connection J22C to J24C J220 to J240 J22E to J24E Table 2-5: Reference Resistor Connections 2.1.4 Lower Multiplexor Controls The pinout of the lower multiplexor (MUX) control connector (lower board -J6) is shown in Table 2-6. This connector is intended to connect to the MUX in the lower unit. The additional MUX signals (MUX4 and MUX5) would increase the total number of possible thermistors to 52. The +12 V, -12 V and +5 V supplies are intended to power the MUX in the lower unit. The MUX signals are driven by a 74LSO4 inverting buffer. These output signals have TTL logic levels. I ~M~ I I Table 2-6: Lower MUX Control Signals I I 2.1.5 Jog Detector Inputs The pinout of the jog detector connector (lower board -J7) is shown in Table 2-7. This connector is intended to interface to a traditional geophone. The gain required to trigger a jog can be adjusted with potentiometer R56. To aid in tuning the gain the audible jog detect jumper 08) can be populated. The buzzer will ring for a fixed period of time every time the JOG signal is asserted. . I Table 2-7: Jog Detector Signal Description 2.2 Upper Board External Connections .I The connectors on the upper board are shown in Figure 2-3. I I I .lt1iiii~ DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 / January 10, 2000 '" "Ej 8 '" /I I I ~ \ / '\ ~"" "" "" ~0 / ,/ / / Figure 2-3: Upper Board External Connector Location I The function of each of the connectors is shown in Table 2-8. A detailed description of each of the connectors is presented in the following sections. Table 2-8: Upper Board External Connector Description 2.2.1 Heater Power Supply The pinout of the heater power supply (upper board -}8) is shown in Table 2-9. This connector is intended to interface to the battery pack for the high power heat pulse electronics. This battery pack should be 28 volts. The heat pulse circuitry can handle up to 20 amps. AliII~ DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 I January 10, 2000 9 Table 2-9: Heater Power Supply 2.2.2 Pinger Power Supply The pinout of the pinger power supply (upper board -J4) is shown in Table 2-10. This connector is intended to interface to the battery pack for the pinger electronics. This battery pack should be 36 volts. The maximum output power of the pinger is 50 watts RMS. Assuming an efficiency of 95%, the current draw from the battery would be approximately 1.5 amps. I Table 2-10: PinKer Power Supply I 2.2.3 Pinger Connection The pinout for the pinger (upper board -J5) is shown in Table 2-11. This connector is intended to interface to the ITC-3013 transponder. The two terminals connect directly to the transformer and inductor. The pins were arbitrarily labeled the positive and negative terminal. The orientation of these signals can be either way. Reference Designator and Pin Number TS-Pint Description Signal Direction with Respect to Instrument Output Output Positive Terminal Negative Terminal Table 2-11: Pinger Connection I I AM~ 2.2.4 Isolated RS-232 The pinout for the RS-232 connector (upper board -J7) is shown in Table 2-13. A cable can be made to connect the serial port of a standard PC to this device. The connections required for a 25-pin and a 9 pin PC serial port (usually a DTE device) are shown in Table 2-12. For example a PC with a 9 pin serial port should have the TXD signal on pin 3, the RXD signal on pin 2 and the ground signal on pin 5. The TXD, RXD and GND signals on the PC serial port connect to ISO_TXD2, ISO_RXD and GND respectively on the HFP serial port. Table 2-12: Serial Connections for PC DTE Reference Designator and Pin Number I Description Signal Direction with Respect to Instrument Input ]7-Pinl ]7-Pin2 Output T7-Pin3 Invut RS-232 Input Signal aSO_TXD2) R5-232 Output Signal (ISO_RXD2) Ground Table 2-13: Isolated RS-232 Signals 2.2.5 Electronics Power Supply The pinout of the electronics power supply (upper board -Jl) is shown in Table 2-14. This connector is intended to interface to the electronics battery pack. This battery pack should nominally be 18 volts. The DC to DC converter that runs off this battery pack will operate properly on an input voltage ranging from 9 volts to 18 volts. I Table 2-14: Electronics Battery Pack I January 10, 2000 DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 11 2.2.6 Heater Connection I I The pinout for the heater (upper board -J9) is shown in Table 2-15. The load resistor is connected across this connector. The 4-pin connector should be used as a Kelvin connection. The high current leads of the load should be connected to pin 1 and pin 4. The sense leads should be connected to pins 2 and 3. Reference Designator and Pin Number ~ J9 -Pin 1 J9 I + Heat Pulse + Sense CoImection Sense CoImection Heat Pulse ~~ :Pin2 J9-Pin3 I Description Signal Direction with Respect to Instrument Outout T9-Pin4 Table 2-15: Heat Pulse Connection 2.3 Lower Board Jumper Settings The jumpers on the lower board are shown in Figure 2-4. The purpose of these jumpers is discussed in the following sections. / '""'" / / / / \ \ I \ \ .J8 CJ \ \ \ ~o ~ """ " " " / ~ I~ ,/ / ~ /' Figure 2-4: Lo,ver Board Jumper Location ,/\MIRiX / / / /I \ DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 January 10, 2000 12 2.3.1 Analog to Digital Converte r Microcontroller Programming Jumpers The majority of the jumpers are associated with programming the 89C51 microcontrollers. In the operational mode the serial communication lines (RXD and TXD) are used to communicate with the Tattletale8. These signals have an alternate function when in the In System Programmable (ISP) mode. In the ISP mode the serial communication lines are used to communicate program data. The jumpers (JP3, JP4) need to be populated for normal operation. To program the device the jumpers should be removed and then the serial communication (RXD and TXD) can be driven via J23. The programming header J23 can be connected to a PC serial port with an RS-232 to 1TL converter. The device can then be reprogrammed with the appropriate software. The jumper configuration for both modes of operation are described in Table 2-16. I On reset of the device the 89C51 samples the status of the PSEN signal. If this signal is high (or not connected) the device branches to address OxOOOO where the normal operation application code exists. If this signal is tied low the device branches to address OxFCOO where the ISP boot loader exists. To issue a reset to the device the JP2 jumper can be removed and the pushbutton pressed. The 89C51 device is a FLASH based part. In order to program the FLASH a 12-volt supply is required. To program the device the EA/Vpp signal 04 -Pin 2) must be connected the 12-volt supply 04 -Pin 1). For normal operation the EA/Vpp signal 04 -Pin 2) must be connected to the S-volt supply 04 -Pin 3). The EA/Vpp signal 04 -Pin 2) should not be left open. If the pin floats low then the device may attempt to fetch code from external memory (which does not exist). The jumper configuration for both modes of operation are described in Table 2-17. Designator I Description Populated Not Populated Pushbutton Controlled Programming mode JP2 ADC Microcontroller Reset Selection n'8 Controlled JP3 AOC Microcontroller RXD Connection JP4 ADC Microcontroller TXD Connection JPS AOC Microcontroller Normal operational mode Normal operational mode Programming mode PSEN Programming mode Normal operational mode Table 2-16: 2-Pin Jumpers Associated with Programming the ADC Microcontroller AM~ Desip;nator -,~!!pt~on J4 AOC Microcontroller 13 January 10, 2000 DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 Pin 1 to Pin 2 Pin 3 to Pin 2 Programming mode Normal operational mode Table 2-17: 3-Pin Jumpers Associated with Programming the ADC Microcontroller 2.3.2 Audible Jog Detector lndic ator The piezoelectric buzzer is intended to aid the adjustment of the gain in the jog detector circuitry. The Audible Jog Detector Enable jumper can be populated to enable the buzzer. For normal operation this jumper should be removed. Oesi ator Oescri Po ulated Not Po ulated J8 Audib Detector Enable Enabled Disabled Table 2-18: Audible Jog Detector Indicator 2.4 Upper Board Jumper Settings The jumpers on the upper board are shown in Figure 2-5. The purpose of these jumpers is discussed in the following sections. '""'" "\ / / /I \ , r=J.a §~ / \ ~ / "" '"'" / / '" /' ~ --'" Figure 2-5: Upper Board Jumper Location I / I DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 !anUllry 10, 2000 14 2.4.1 Pinger Microcontroller Programming Jumpers For a description of these jumpers in Table 2-19 and Table 2-20 refer to Section 2.3.1. The jumpers used by the pinger microcontrolIer are similar in function to the jumpers used on the analog to digital converter microcontrolIer I Populated Designator I Description I JPl JP2 JP3 JP4 I I Pinger Microcontroller 1T8 Controlled Reset Selection Normal Pinger Microcontroller operational RXD Connection mode Pinger Microcontroller Normal operational TXD Connection mode Pinger Microcontroller Programming mode PSEN Not PoDulated Pushbutton Controlled Programming mode Programming mode Normal operational mode Table 2-19: 2-Pin Jumpers Associated with Programming the Pinger Microcontroller Desienator I Description J3 PinltoPin2 Pinger Microcontroller Programming mode Pin 3 to Pin 2 Normal operational mode Table 2-20: 3-Pin Jumpers Associated with Programming the Pinger Microcontroller 2.4.2 Pinger Frequency Select Jum pers The remaining three jumpers UP8, JP7, JP6) select the frequency of the pinger. Pinger Frequency Pin2er FreQuency Select Jumpers IPS populated populated populated populated unpopulated unpopulated unpopulated unDoDulated JP7 populated populated unpopulated unpopulated populated populated unpopulated unpopulated JP6 populated unpopulated Eopulated unpopulated populated unpopula!ed populated unDopul~ed (kHz) 5.9956 7.9942 9.0066 9.9879 11.000 0 11.991 3 13.012 Table 2-21: Pinger Frequency Selection 6 13.9831 3. Hardware Reference 3.1 Introduction This section is not intended to be a complete hardware reference that covers all aspects of this design. A lot of the detail has already been captured in the Conceptual Design Document (DN:1518). This section will highlight any differences from the Conceptual Design Document. I 3.2 Thermistor Analog to Digit al Conversion -Lower Board 3.2.1 Slew Rate Limiting of Amp lifiers One problem associated with the switched DC bridge technique is the slew rate limiting of the operational amplifiers. The simplified schematic of the analog thermistor section is shown in Figure 3-1. This is a copy of the schematic that was shown in the conceptual design document and has been included here for reference purposes. Recall that the bridge is exciting by an alternating +5 volt -5 volt square wave. The amplifiers A1, A2, A3, A4 all experience slew rate limiting. Precision amplifiers were chosen for their low offset voltage drift versus temperature. Unfortunately precision amplifiers typically do not have fast output stages causing rather poor slew rate limiting. Figure 3-1: Thennistor Analog Section DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 16 January 10, 2000 The result of the slew rate limiting can be observed at the input to the voltage to frequency converter. Ideally this voltage should be a constant DC voltage. The actual voltage is shown in Figure 3-2 indicated as U4-1. From a performance point of view this effect seems to manifest itself as a nonlinearity. The nonlinearity of the measurement improves if the bridge is fixed at a constant 5 volt excitation. The nonlinearity appears to increase as the number of bridge reversals (number of CLK_RMS cycles) is increased. ~; ~: ~."j: I~'-'_~'..-::'lf-_'..I.II.II~l.~_,r.I~- -:;-:_-::~I'l~ @: CD 0.00 V 7.10 V 2. OO}ls 179}ls u6-6 ;_.+-..; ! ;-..;...+-+-!"-.; ;.+t-++.++~.;-+++-: 8- u4--1 .-1-'._.; J I._.I...J I , ,...J ; ...'-J...';'_.'_..' ' I-'-1 ' -J , , , L.; , L..-, L.I.-.' , 1 Ch1 5.00 V ew- 5.00 V M 100).15 A Ch2 '\. 1.30 V 0-+'" 177.400]JS 7 SeD 1999 06:43: 16 Figure 3-2: Effect of Amplifier Slew Rate Limiting In an attempt to reduce the nonlinearity, a schottkey diode was added between pin 7 on the VtoF converter (5 VIN) and ground. This did improve the nonlinearity slightly but this is still not as good as with a fixed DC bridge excitation. The nonlinearity is shown in Figure 3-3 for three different test cases. The normal operation is shown as the "No Cap" trace. The operation with a fixed DC bridge excitation is shown as the trace labeled "No RMS". The normal operation with the diode connected to pin 7 (5 VIN) on the VtoF is shown as the trace labeled "Diode". A:M~ I January 10, 2000 DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 17 In conclusion, the majority of the nonlinearity is due to the switching of the bridge. The addition of the diode improves the situation slightly. The slight improvement was not considered enough to warrant modifying the design to include the diode. The nonlinearity can be decreased by reducing the number of bridge switches within a measurement. Residuals 400 ~ 300 -200 0 - No Cap -+Eo- Diode --No RMS c ~ 100 0 (.) -0 "'(ij ~ 'C -100 ~ 0 ~ -200 -300 -400 1.8 I I m 1.9 2 2.1 2.2 2.3 2.4 Resistance (kOhm) 2.5 2. 6 2. 7 Figure 3-3: Nonlinearity Error 3.2.2 Offset Resistor Settings The Tattletale controls the input range used for the thermistor measurements. The offset selected can range from 0 to 7. The offset setting determines the parallel combination of resistors (R15, R16, R17, R18 on the lower board) used for the offset resistor. The offset resistor (often referred to as Ro in Dalhousie documentation) is one of the resistors in the nonthermistor arm of the bridge. The offset resistor determines the balanced operating point of the bridge. The input range for each of the offset settings is shown in Table 3-1. PSPICE simulations were used to determine the upper and lower limits of the range. Actual values will vary from these values. In the table the " j j" indicates the parallel combination of resistors. ~M~ DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 January 10, 2000 18 I Table 3-1: Input Range versus Offset Setting I 3.2.3 Gain Resistor Settings The gain of this bridge circuit is determined by the amount of feedback around the bridge. The amount of feedback is set by a resistive divider consisting of R20 and R22. The Tattletale can change the gain by switching a resistor, R19, in parallel with R20. The current Heat Flow Probe configuration does not populate R19. There was not a specified gain for the second gain setting therefore a resistor value could not be determined. This functionality existed in the original design and was not deleted in the new design. If in practice gain changes are required then this resistor can be populated appropriately. 3.2.4 Balance Adjust To reconstruct a steady positive voltage, at the input of the VtoF, from the alternating DC Bridge an inverter amplifier is required. The MUX (U4) alternately selects the inverting and then the noninverting path to reconstruct a DC voltage. The potentiometer (RIO) in the inverting path is used to null out the offset associated with this inverting amplifier stage. 3.3 Voltage and Current Monit orB -Upper Board I 3.3.1 Heat Pulse Voltage Monito r The voltage across the heater is used to calculate the power delivered to the load. The voltage across the load is scaled by a resistive divider consisting of R26 and R27. This scaled voltage is then passed through an instrumentation amplifier with a gain of unity. The total gain from voltage across the heater coil to the voltage at the Tattletale input is given below. DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 January 10, 2000 (volts/volt) 19 Equation 3 The input range of the Tattletale's analog to digital converters is from OV to 4.096V. Given this range the heat pulse voltage monitor will operate properly with inputs ranging from OV to 24.576V 3.3.2 Heat Pulse Current Monitor The current through the heater coil is sensed with a 0.01 Ohm current sense resistor (R31). The voltage across this resistor is amplified by an instrumentation amplifier (U13) with a gain of 10. The transfer function from the current through the heater coil to the voltage at the Tattletale input is given below. Gain =0.01* 100000 R32 =0.1 (volts/amp) Equation 4 The input range of the Tattletale's analog to digital converters is from OV to 4.096V. Given this range the heat pulse current monitor will operate properly with inputs ranging from 0 amps to 40.96 amps. 3.3.3 Heat Pulse Battery Pack Monitor The voltage at the heat pulse battery pack is used to determine when the battery pack is nearly depleted. The voltage at the battery pack is scaled by a resistive divider consisting of R22 and R23. This scaled voltage is then passed through an instrumentation amplifier with a gain of unity. The total gain from voltage across the heater coil to the voltage at the Tattletale input is given below. (volts/volt) Equation 5 This voltage monitor should return the same value as the heat pulse voltage monitor when the heat pulse is active. When the heat pulse is inactive this voltage monitor reads the actual voltage on the battery pack while the heat pulse voltage monitor will be pulled low. I The input range of the Tattletale's analog to digital converters is from OV to 4.096V. Given this range the heat pulse voltage monitor will operate properly with inputs ranging from OV to 24.576V. DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 January 10, 2000 20 3.3.4 Pinger Battery Pack Monito r The voltage at the pinger battery pack is used to determine when the battery pack is nearly depleted. The voltage at the battery pack is scaled by a resistive divider consisting of R22 and R23. This scaled voltage is then passed through an instrumentation amplifier with a gain of unity. The total gain from voltage across the heater coil to the voltage at the Tattletale input is given below. (volts / volt) I Equation 6 The input range of the Tattletale's analog to digital converters is from OV to 4.096V. Given this range the pinger battery pack monitor will operate properly with inputs ranging from OV to 35.6037V 3.3.5 Electronics Battery Pack The voltage at the electronics battery pack is used to determine when the battery pack is nearly depleted. The voltage at the battery pack is scaled by a resistive divider consisting of R3 and R4. This scaled voltage is then passed through a noninverting operation amplifier stage with a gain of 2.05 V IV. The total gain from voltage across the heater coil to the voltage at the Tattletale input is given below. = 0.235841 (volts/volt) Equation 7 The input range of the Tattletale's analog to digital converters is from OV to 4.096V. Given this range the electronics battery inputs pack monitor will operate properly with ranging from OV to 17.3676V. 3.3.6 Isolated Grounds The ground reference for the heat pulse battery pack and the pinger battery pack are isolated from the ground reference for the electronics battery pack on the boards. The instrumentation amplifiers (used by the monitors) are used to bridge the two ground references. However the instrumentation amplifiers do require a resistive connection between the grounds. There are two resistors (R33 and R20 on the upper board) that provide this resistive connection. These resistors are currently populated with 100 Ohm resistors. If the grounds for each of the battery packs are common then these resistors can be removed to eliminate any possibilities of ground loops. DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual Vl.0 January 10, 2000 21 4. Assembly Instructions This document describes the assembly instructions for the Dalhousie Heat Flow Probe. This unit consists of two boards: the upper board and the lower board. The assembly instructions have been organized into three sections the assembly instructions, the ECO list and assembly notes. The assembly instructions deal with any components that are unaffected by any ECO changes. If a component was changed due to an ECO it would have been removed from the assembly instruction section and a new instruction added to the ECO list. I The following documentation is relevant to these assembly notes. For each of the boards there are two appendices containing schematics. The Original Schematics were used to layout the board. The Revised Schematics contain all the ECO's and component changes backannotated onto the schematic. ~ . I i I I I Lower Board Original Schematics Revised Schematics Bill of Materials Assembly Drawings Mechanical Drawing SCH-OO211O-Q1 SCH-OD2110-D2 BOM-DO2114-D2 MECH-OO2116-01 MECH-OO2249-D1 Appendix Appendix Appendix Appendix Appendix I Upper Board Original Schematics Revised Schematics Bill of Materials Assembly Drawings Mechanical Drawing SCH-OO2109-01 SCH-OO2109-D2 BOM-DO2113-D2 MECH-OO211S-DI MECH-DO2249-DI Appendix C Appendix D Appendix F Appendix H Appendix J A B E G January 10, 2000 DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 22 4.1 Upper Board Assembly 1. Populate the following components. Qty. Reference Desianator 9 C1, C2, C4, AM Part Manufacturer Part Number Number 2885 ECS- T1 ED226R Description Manufacturer Panasonic 22uf Tantalum SMT Cap C5, C6, C40, C41, C42, C43 16 C3, C7, C8, I 2886 ECJ-1VF1 E104Z Panasonic C9, C11, I C12, C13, C14, C16, C17, C22, C23, C24, C25, C26, .1uF, 25VDC Cap, 0603 C27 1 C10 2992 PCS31 06CT -NO Panasonic 10uF Tanatalum, 3528 I 1 C15 2964 C18, C19, 2840 ECE-A 1JGE471 Panasonic Electrolytic Capacitor, 470uF,63V 3 ECS- T1EY105R Panasonic volts C20 C21 1 uF Tantalum Cap, 25 2841 ECS-T1CY475R 2994 8130DICT -ND I Panasonic 4.7uF Tantalum Cap, 16 volts 1 I D1 IR Schottkey, SMA, 30 amps 3 02,03,04 4232 BAS16 ROHM Switching Diode 6 F1, F2, F3 2862 122088 Littelfuse Fuse Clips, PCB 5 1501, 1502, 2819 PS2701-1NEC-ND I NEC 2930 PZCO2SMN Sullins Jumper, 2 Pins 5760 TSW-105-08-G-D- Samtec 2x5 Right Angle Mount Optical Coupler, SO4 1503,1504, 1505 7 JP1. JP2. JP3, JP4. JP6. JP7, JP8 IJP5 RA terminal strip 3 J4. J5, J8 2905 277-1027-ND Phoenix 1 J3 2931 PZCO3SAAN Sullins 2 Pin 5.08mm Screw Terminal .l\:M~ Jumper, 3 Pins, G~ DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 Oty. Reference Desianator 1 J6 J7 AM Part Manufacturer Part 2865 Manufacturer Description Number Number 5682 January 10, 2000 SSW-108-01-G-D Samtec 1803439 Phoenix 1 20 socket dual row connector 1 3 contact Connector header, Vertical, 3.81mm 1 1 J22 2966 640457-4 AMP J9 2920 277-1249-ND Phoenix PZ1 2852 AI-175 Projects 640457--4 Right An Ie Connector 4 position 5.08 mm Screw Terminal Sub miniature Piezo Unlimited Audio Indicator 2 01,03 2820 MTP4N50E 4 02, 04, OS, 2814 MMBT2222L T1 6006 P1MOACT-ND Panasonic 1M, 5%, 0805 R2 6015 P10K5CCT-ND Panasonic 10.5K, 1%,0805 RS, R6, R8, 3010 P10KOCCT -ND Panasonic 10K, 1%,0805 4490 P100KCCT-ND Panasonic 100K, 1%,0805 6008 P3K9ACT -NO Panasonic R21 4900 PORECT -ND R31 2821 MP916-.01 07 3 R1, R68, Motorola Power FET Motorola NPN Transistor R69 4 R32 7 R3, R7, R10, R22, R2S, R26, R29 3 R13, R19, ! 3.9K, 5%, 0805 R28 I 1 1 R30 N/A 1 R24 N/A 3 R15, R16, N/A P391 OR, 5%, 1206 I Panasonic I .01 ohm Precision I Caddock Power Resistor ECT-ND Panasonic P102VCT-ND Panasonic P512ACT -ND Panasonic N/A P681 ECT -ND Panasonic N/A P222ECT Panasonic N/A P133CCT-ND Panasonic N/A P203CCT -ND Panasonic 1428 RM782AT151J KOA 2842 EVQ-QHVO2W Panasonic i 390, 5%, 1206 11K, 5%, 1210 I I 5.1K. 5%, 0805 I R17 I 2 R11, R14 2 R12, R18 2 R4, R9 2 R23, R27 2 R20, R33 51 1 T2 U2 i 680, 5%, 1206 -ND 2.2K, 5%,1206 13K, 1%,0805 20K, 1%,0805 100,5%,0805 Pushbutton Switch, SMT Transformer 2816 67117970 Schott Corp. 2892 LM2904M-ND National Dual Low Power CD-amp 23 DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 January 10, 2000 I 2. Populate the terminal plugs so the notch points into the board. This ensures that the wires are oriented off the board instead of over the top of the board. Qty. Reference Desianator 1 J1 J'M Part Manufacturer Part Number Number 2866 1803426 Manufacturer Phoenix Description 2 contact Connector header, Vertical, 3.81mm 1 J7 2865 1803439 Phoenix 3 contact Connector header, Vertical, 3.81mm 3. Populate the fuse holders. I I AMI~ 24 4. Assemble and attach the POT cores. Qty. Reference AM Part Manufacturer Part Designator Number L1 2882 Manufacturer Description Number 991-193-00 Philips Magnetics 2883 991-199-00 Philips Magnetics 2884 991-191-00 2880 3622PA275-3C81 Terminal Plate for 36x22 core 1 Brass Cover for 36x22 core _~hil!ps Magnetics I Spring for 36x22 core Philips Magnetics Pot Core, 36><22, Gapped, 3C81 1 5686 3622F1D Philips Magnetics Bobbin 2882 991-193-00 Philips Magnetics Terminal Plate for 1 2883 991-199-00 Philips Magnetics 1 2884 991-191-00 36x22 core Philips Maanetics I Sprina for 36x22 core 1 2881 3622PLOO-3C81 Philips Magnetics 1 5686 3622F1D Philips Maanetics I Bobbin 1 T1 36x22 core I Brass Cover for Pot Core, 36x22, UNGaDDed. 3C81 5. Populate the jumpers. Reference Designator I Status ~ Populate Populate PoDulate .TP2 JP3 Povulate Pin 2 to Pin 3 I I I I AM~ DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 January 10, 2000 26 6. Populate Q6. Bolt the transistor to the board with the machine screw and nut. Populate the DC to DC converter (U3). It is important to note that the DC to DC converter must be populated after the transistor is bolted down. The head of the screw is counter sunk under the DC to DC converter. 4.2 Upper Board ECO List 1. Connect U1 pin 57 to +5V. The ECO must be attached to the Tattletale footprint so that it does not interfere with the Squishy bus connector. The pullup resistor R1 is attached to +5V. This may be the most convenient place to attach the ECO wire to. 2. The serial communication lines between the TattleTale and the two 8051s are not crossed on the board (TXD goes to TXD and RXD goes to RXD). Therefore, the traces connected to pin 18 and pin 19 on the Tattletale pad need to be cut before the first via and crossed using wire. 3. On the original schematics and board, REFADJ (pin 99) is connected to VREG (pin 110) on the TattleTale. This connection needs to be broken. The trace from pin 99 can be cut before it hits the first via underneath the TattleTale. 4. Before attaching the Tattletale, check that the Tattletale's step down DC/DC converter (LTCl174) is configured to supply 600mA. Pin 7 (Ipgm) should be lifted from its pad and connected to pin 6 (Vin). All of the hardware to attach the Tattletale and Persistor FLASH card to the Upper Board should be included with the Tattletale. I 5. Two pull-up resistors are required on the emitters of the two optocouplers used in the isolated RS232 driver circuit. On U9 (MAX250CPD) connect pin 10 (RIIN) to pin 14 (YCC) using a lK resistor. Instead of using pin 14, the positive side of capacitor C20 may be used. On UI0 (MAX251CPD) connect pin 3 (TIIN) to pin 7 (BYPASS) using a lK resistor. Instead of using pin 7, the positive side of capacitor C21 may be used. Both resistors could possibly be mounted underneath the sockets for U9 and UI0. Qty. Reference Designator 2 R70, R71 AM Part Manufacturer Part Number 5834 Manufacturer Description Number CFR12JR1KO Yaego 10K leaded 1/8W resistor 6. Populate the sockets for U9, UlO. Qty. - Reference AM Part Manufacturer Part Desianator Number U9 2871 Manufacturer Description AR14-HZL Assmann 14 pin Machined IC AR14-HZL Assmann 14 pin Machined IC 1 Sockets 1 U10 2871 Sockets 7. I Populate the socketed RS232 parts. 8. The SHUTDOWN signal on U9 (MAX250CPD) was originally intended to be controlled by the TattleTale. However, we cannot guarantee this port line to be set properly when running the TattleTale in PicoDOS or other debugging tools. Hence, we may loose communication with the unit. Therefore, pin 1 on U9 needs to be connected to ground and disconnected from the signal line by either lifting the pin, or cutting the trace. Pin 1 can be connected to the positive side of C6 to be grounded. It may possible to put this ECO under the socket to improve the appearance of this ECO. A:fiii,~ 4.3 Upper Board Notes 1. The footprint for 06 (89C51RC) appears to be incorrect. The leads on the device are longer than the pads, which may cause some problems when soldering the device. This should be corrected if the board is laid out again. 2. The silkscreen labels for resistors R23 and R33 are interchanged on the actual board layout. Therefore, the slot marked R33 needs to be populated with R23 and the slot marked R23 needs to be populated with R33. Check the assembly diagram. Do not trust the silkscreen. 4.4 Lower Board Assembly I 1. Populate the following components. Qty. Reference Desianator 35 C1, C2, C3, AM Part Manufacturer Part Number 2886 Manufacturer Description Number ECJ-1 VF1 E1 042 Panasonic C4, C6, C7, .1uF, 25VDC Cap, 0603 C8, C9, C10, I C11, C12, C13, C14, C15, C16, C17, C18, C19, C21, C22, C23, C24, C25, C26, C27, C29, C30, C31, C32, C33, C36, C37, C38, C39, C50 I 1 C5 2887 ECQ-P1H223GZ 2 I C20 2840 ECS- T1 EY1 05R Panasonic 1 uF Tantalum Cap, Panasonic 1 uF, 0805 Ceramic Panasonic .O22uf Polypropylene Film Cap 25 volts 1 C34 2961 ECJ-2VF1C105Z 1 C28 2992 PCS-3106CT -ND 1 C35 2901 ECU-V1 H223KBX Cap, 16V Panasonic 10uF Tantalum Cap, 3528 ! Panasonic .022uF Capacitor, §OV,0805 AM~ Oty. Reference DesiQnator 6 C44, C45, AM Part Manufacturer Part 2885 Manufacturer 11 ED226R Panasonic C46, C47, 4 C48. C49 D1, D2, D3, Description Number ECS- Number 22uf Tantalum SMT Cap 4232 BAS16 Rohm Switching Diode Dual Schottky Diode D5 1 D4 2929 BAT54SCT -ND Zetex 1 JP1 5760 TSW-105-08-G-D- Samtec JP2, JP3, 2930 terminal strip RA 5 2x5 Right Angle PZCO2SAAN Sullins Jumper, 2 Pins, Gold PZC03SAAN ZSS- Sullins Jumper, 3 Pins. Gold 108-05-G-D- 915 Samtec 2x8 connector for 1" JP4, JPS, J8 1 J4 2931 1 J9 5759 board spacino 310-93-164-41-001 1 J20, J21, J22, 5685 Mil-Max J24 11 pin IC Strip Header (64 pin to be cut into 4x11) 640457--4 Right 1 8 J23 RS, R7, R21, 2966 640457-4 Amp Anale Connector 6033 2312-241-71004 BCC .1%, 0805 25ppm R23, R6, R9, Resistor, 100K R13. R14 R11 6034 2312-241-79763 ecc .1%, 0805 25ppm Resistor, 4 97.6K 6018 P200KACT -NO Panasonic 200K,5%,O805 R8 3012 P1KOCCT-ND Panasonic 1K, 1%, 0805 R10, R56 R12 2838 3214J-1-203E Bourns Trim Pot, SMT 6017 P39KACT -ND Panasonic 39K.5%,O805 4490 P1 OOKCCT -ND Panasonic 100K, 1%.0805 5798 P1692CCT -ND Panasonic 16.9K, 1%,0805 6035 2312-241-71003 BGG R51, R55, R58, R59 1 1 6 R2, R4, R52, R54, R61, R64 R1, R3 2 R15 .1%, 0805 25ppm Resistor. 10K R16 6066 2312-241-76493 BCC .1%, 0805 25ppm Resistor. 64.9K 1 R17 6037 2312-241-72943 BCC .1%,080525ppm Resistor, 29.4K 1 R18 6038 2312-241-75622 BCC R20 6040 2312-241-77503 eGG .1%,080525ppm Resistor,5.62K 1 .1%,080525ppm Resistor, 75K .A1fii,~ c.. DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 . Qty. 1 Reference Desianator R22 AM Part Manufacturer Part Number January 10, 2000 Manufacturer Description Number I 6039 30 2312-241-72672 BCC '.1%,080525ppm Resistor, 2.67K 1 R40 3010 1 R41 6019 4 R42, R43, P10KCCT -ND P2K2ACT -ND Panasonic Panasonic 10K, 1%,0805 2.2K. 5%, 0805 Select On Test R44, R45 4 2826 P470KACT -ND Panasonic 470K, 5%, 0805 R57. R53 3239 P15KACT-ND Panasonic 15K, R63, R62 2907 P1 K5ACT -ND Panasonic 1.5K, 5%, 0805 R6S 2825 P47KACT Panasonic 47K, 5%, 0805 1 R67 6006 P1MOACT-ND Panasonic M, 5%, 0805 51 2842 EVQ-QHVO2W Panasonic Pushbutton Switch, 1 U1 2892 LM2904M-ND National Dual Low Power 4 U3, U5, U6, 2803 OP177FS Burr Brown Ultraprecision Operational R49, R50, R60, R66 :?:.. 2 1 1 1 -ND 5%, 0805 SMT U11 Amplifier, I S08 2 U4, US 2807 ADG419BRM Analog Devices Dual Precision Analog Switch, uSOIC 1 U7 4925 1 U9 2858 1 U10 2991 1 U12 2809 AD588JO Analog Devices CY37064P44- Cypress CPLD, 44 pin TOFP ADG202AKR Analog Devices Analog Switch, P89C51 RC+JB Philips Precision Voltage Reference 125AC 16S0lC Flash ISP Microcontroller, 32K, PQFP44 1 U13 2808 ADG426BRS Analog Devices 16 Channel Analog MUX, SSOP PackaQe ! Motorola 1 U14 2904 DM74LSO4M-ND 1 U15 2804 MC4741CD Motorola 1 U16 2805 CD4013BCM National 1 X1 2919 SG-636PCE- Epson LS TTL Inverter, SO-14 Quad 741 OP-AMP, 50-14 Dual Flip-Flop, 4000CM08, 80-14 33.000MC2 .II:MI~ 33MHz Oscillator 2. Populate the Ferrite Beads. Use a single loop of 22 Gauge solid wire to attach the ferrite beads to the PCB. Qty. Reference Designator 7 L1, L2, L3, AM Part Manufacturer Part Number 2918 Manufacturer Description Number FB73-226 JW Miller Ferrite Beads, 0-40MHz I I 3. Populate the terminal plugs so the notch points into the board. This ensures that the wires are oriented off the board instead of over the top of the board. f}~1 ~ 4. Populate the jumpers. I 4.5 Lower Board ECO List 1, Before populating 02 there is a trace which must be cut under the device. The trace from 02 pin 12 goes to a via and attaches to one of the planes. The trace must be cut before the via. 02 can then be populated. Attach the 51 pF capacitor Afiii,~ DN: 1626 -Dalhousie Heat Flow Probe Hardware Reference Manual V1.0 January 10, 2000 32 to the board (hot glue or epoxy) close to pin 12. Connect one side of the capacitor to Cos (U2 pin 12) and the other side to ground (U2 pin 16). Qty. Reference AM Part Manufacturer Part Desianator Number Number 1 U2 1 C51 Manufacturer De!iCriptili>n 2806 AD652KP Analog Devices V to F Converter. 5807 PCC510CCT -NO Panasonic 51 pF, 1206, SMT, PLCC20 NPO ceramic capacitor 4.6 Lower Board Notes 1. The footprint for U12 (89C51RC) appears to be incorrect. The leads on the device are longer than the pads which causes some problems when soldering the device. ",fiii;;~ I I I I I I I I I I A1iW~ I - ~- '- 2 ~ ~ I E E ~ 5 ~ ~ I/} .. ~~~ 2~~ ... 0 :I: ~§& .g ~§& ! " ~~ ~~ ~~HII' ~I