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Transcript
BalloonSat Assembly Manual
LaACES Student Ballooning Course
August 2004 (revised 06/01/2007)
S. B. Ellison
Electronics Development Group
Department of Physics and Astronomy
Louisiana State University
Baton Rouge, LA
Description
BalloonSat is a simple micro-controller based development board, which serves as the platform for learning to use
and apply the Parallax BASIC Stamp micro-controller. BalloonSat includes additional memory, an analog-to-digital
converter, a real time clock and large prototyping area. BalloonSat can be used as a simple data acquisition system
in the laboratory or integrated into a student designed balloon payload where it can serve as the payload flight
computer.
BalloonSat is programmed with the Parallax, Inc. BASIC Stamp Editor using the PBASIC language. PBASIC is
version of the BASIC language enhanced with a number of specialized input/output (I/O) instructions well suited for
data collection and control applications. The Stamp Editor runs on a personal computer where user programs are
written, edited, and then downloaded to the BASIC Stamp module. Several different versions of the BASIC Stamp
are available from Parallax, Inc. BalloonSat uses the BS2P24 module.
Background
The BalloonSat design evolved from CanSat, a project conceived by Professor Bob Twiggs at Stanford University's
Space Science Development Laboratory. The original CanSat included an auxiliary EEPROM memory chip for data
storage and a modem (modulator-demodulator) to allow connection to an external radio transmitter and receiver.
The LaACES design for BalloonSat eliminates the modem of CanSat, but provides a number of enhancements
including a 4-channel analog-to-digital converter, voltage reference, temperature sensor and 4 on-board LED’s for
use as visual indicators. CanSat provided pins for connecting external hardware. BalloonSat retains these expansion
pins but provides a prototyping area with GND and VCC power buses for use by user provided components or
circuits.
Theory of operation
Operation of BalloonSat is best understood by referring to the BalloonSat Block Diagram and the BalloonSat
schematic diagram. Integrated circuit U1 is the Parallax BS2P24 micro-controller module. This module looks
somewhat like an integrated circuit but is actually a hybrid containing several integrated circuits, transistors and
passive components on the 24 pin dual-in-line carrier. This component alone, with a suitable power source and
connection to a personal computer running the Parallax software is a self-contained microcomputer. The BASIC
Stamp module contains on-chip flash memory for program storage. Once programmed, the BASIC Stamp can be
disconnected from the personal computer. The BASIC Stamp begins execution of its downloaded program on
power-up.
06/01/2007
BalloonSat Assembly Manual
1
U3
+5 VDC
REGULATOR
V IN
+5VDC
Personal
Computer
RS-232
DS1
DS2
DS3
DS4
P7
P6
P5
P4
U1
BASIC
STAMP
BS2P24
I/O
Pins
P0 – P7
P14
P15
P13
Ch 0
Ch 1
I/O
Pins
P8 – P15
U4
ADC
U5
V REF
Ch 2
U6 Ch 3
TEMP
SENSOR
P8
U2
EEPROM
MEMORY
VBATT
P9
P10
U7
REAL
TIME
CLOCK
P12
P11
BalloonSat Block Diagram
The major functional subsystems of BalloonSat are depicted in the block diagram. The schematic diagram shows all
the components and electrical connections. The BASIC Stamp and other integrated circuits all require a clean,
stable +5VDC power source, commonly designated as VCC. BalloonSat will accept an external DC power source of
+9 to 15VDC. Diode D1 (in the schematic diagram) is a protective device to prevent damage which would be caused
by connecting a power source of the wrong polarity. Voltage regulator U3 maintains a constant +5VDC output
under conditions of changing input voltage or amount of current required by BalloonSat. The regulator can supply
enough current for all of BalloonSat’s on-board components as well as some user supplied circuitry connected to the
expansion pins or the prototyping area. You should consult the U3 datasheet and make a careful estimate of the
power required by any added electronics. Under some conditions, U3 may run hot. A heat sink could be required to
help maintain U3 at a safe temperature.
The simplest I/O subsystem consists of LED’s DS1 – DS4. The individual LED’s are controlled by I/O pins P4, P5,
P6, P7. The series resistors shown in the schematic limit the current to a safe value. These I/O lines could be used
for other purposes but the series resistors R1, R2, R3, R4 and/or the LED’s might need to be removed, particularly if
these pins are needed as input bits. The values of R1-R4 can be changed if more or less current is desired.
The other peripherals, EEPROM, ADC, and RTC communicate with the BASIC Stamp via a synchronous serial
interface. The block diagram summarizes which I/O pins are used for each device. The BASIC Stamp always serves
06/01/2007
BalloonSat Assembly Manual
2
as the master device in synchronous serial communication. The master initiates all operations and generates the
required serial clock signal. Various protocols have been established in the industry for doing synchronous serial
I/O. Some common protocols are the Inter-Integrated Circuit (I2C) developed by Phillips Semiconductor, Microwire
from National Semiconductor, Serial Peripheral Interface (SPI) created by Motorola and the Dallas Semiconductor
OneWire protocol. Component datasheets will usually describe the protocol used in sufficient detail for writing and
debugging user programs. Example circuits and programs are often available from the chip manufacturer’s
databooks or websites.
The BASIC Stamp has a flash memory for storing the executable program and a limited amount of RAM (random
access memory) for variables and data. The flash memory retains the program even if power is lost. The RAM is
volatile, data is lost on power failure. U2, a 24LC64, is an electrically-erasable-programmable-read-only-memory
(EEPROM) integrated circuit. EEPROM is non-volatile but can be erased and used again. Most EEPROM’s have a
limited number of write cycles before it “wears out” but this is usually on the order of 50,000 writes. It is possible to
“wear out” the EEPROM if a user program “runs away” and repeatedly writes to the EEPROM chip. Inadvertently
placing a write routine in an endless loop is a common programming mistake. Fortunately, the EEPROM chip used
in BalloonSat is not expensive. U2 conforms to the I2C synchronous serial protocol using I/O pin P8 as the bidirectional data line and P9 as the serial clock. See the 24LC series datasheet for details of using the EEPROM.
It is often necessary or desirable to have the current time and/or date available to a BASIC Stamp program. For
example, a data logging application may need to save a measurement along with the time/date of the measurement
for later analysis. Applications may need to perform operations at specified intervals or times or to log the time and
date of an event that occurs. It is possible to program the BASIC Stamp to perform time keeping but a better
approach is to have a dedicated RTC (real time clock) that continually runs regardless of what other tasks the
BASIC Stamp may be performing. Usually an RTC will also have provisions for continuing to run even through a
power outage. BalloonSat uses a Dallas Semiconductor DS1302 time keeping chip with provisions for an external
backup battery. An external battery can be connected to P3 on the BalloonSat board. There is no reverse polarity
protection on this circuit. The current requirements are so small that a backup battery will typically last its shelf life
for this type of application. For extreme environmental conditions the choice of battery does require some care.
Review the DS1302 datasheet for voltage and current requirements. Note that this backup battery only serves the
RTC. The other system of BalloonSat still require the VCC supply for proper operation.
The DS1302 uses a simple three wire serial interface. I/O pin P11 is used as a serial clock. I/O pin P10 is the bidirectional data line, and I/O pin P12 is a chip-select for the DS1302. Although BalloonSat has only U7 connected
to these I/O pins, the chip select function allows multiple peripherals to share the same clock and data lines as long
as only one of the bussed chips has its chip-select line asserted. U7 requires crystal Y1, a 32.768 kHz resonator, as
the frequency determining element of its internal oscillator.
BalloonSat features an 8-bit Analog-to-Digital converter with an on chip 4-channel input multiplexer. This IC,
designated U4, is a National Semiconductor ADC0834. The multiplexer allows up to 4 input voltages to be
digitized by a single ADC. An Analog Devices AD780 voltage reference integrated circuit provides a selectable 2.5
or 3.0 volt reference for the ADC. Jumper JMP2 is provided on the BalloonSat printed circuit board for selecting the
desired reference level. Leaving the jumper removed selects 2.5 V. Placing a shorting jumper at JMP3 connects pin
8 of U5 to GND, selecting 3.0 V as the reference output. The AD780 has an internal temperature transducer
providing a 2 mV/oC output. As shown in the block diagram and schematic, the TEMP output from U5 is amplified
by opamp U6. Resistors RV1, R5 and R6 determine the voltage gain of this stage. Variable resistor RV1 can be
adjusted by a small screwdriver for fine adjustments.
The output from U6 can be connected to Ch3 of the ADC. On the BalloonSat board jumper JMP3 allows selecting
either the amplified temperature transducer signal or an external voltage source as the input to Ch3. Pads are
provided on the circuit board for connecting inputs to the ADC channels. The safe voltage level for these signals is 0
(GND) up to the reference voltage (2.5 or 3.0). External signal conditioning electronics may be required to interface
other levels.
The ADC0834 communicates with the BASIC Stamp with the MICROWIRE synchronous serial interface. I/O pin
P14 is the serial clock, pin P13 is the data line, and P15 is the chip select. Notice in the schematic that the DI (data
in) and DO (data out) are both connected to P13. The BASIC Stamp, under software control, will configure P13 as
an input or an output depending upon whether the ADC is being written to or being read. It would also be possible to
06/01/2007
BalloonSat Assembly Manual
3
have separate data in and data out I/O lines but it is frequently necessary to conserve I/O pins, particularly in larger
systems.
BalloonSat can be expanded even further via connector P2. This optional feature allows a connecting external
circuitry to the BASIC Stamp I/O pins. All of the I/O lines, P0 through P15, GND and VCC are available on P2.
When designing devices which will interface to the BASIC Stamp I/O pin usage must be allocated to prevent
contention of devices. It is possible to have multiple I2C devices sharing the same hardware I/O lines if each device
has a unique I2C address. MICROWIRE devices can share clock and data lines but must have individual chip selects
to prevent bus contention. It might be necessary to disable some of BalloonSat’s internal devices if they are not
needed for a given application. This will free I/O pins for use by external peripherals. Of course, caution must be
exercised not to apply negative voltages or voltages greater than +5VDC to P2 or any of BalloonSat’s connections.
Frequently there is a need to create a custom circuit as part of BalloonSat but without the time and expense of a
separate circuit board. The prototyping area provides space for soldering components directly on BalloonSat. Pads
are provided for GND and VCC and for the BASIC Stamp I/O lines P0 through P15. It is best to draw the desired
circuit and layout a tentative component placement plan prior to actually beginning soldering components to the
BalloonSat board. Components can be unsoldered and removed but there is always the possibility of damaging the
circuit board by excessive heat from the soldering iron. Be sure that BalloonSat’s power supply has been
disconnected before mounting or soldering components in the prototyping area. Be careful not to short connections
to GND or VCC. After any modifications, visually inspect the prototyping area before powering up BalloonSat.
If high current devices such as some incandescent lamps, motors or relays are connected to BalloonSat they should
not be connected to VCC unless the total current required is well under 1 ampere and has a relatively low duty cycle.
A separate power source for high current loads is recommended.
06/01/2007
BalloonSat Assembly Manual
4
ASSEMBLY – Stage 1
BalloonSat will be assembled in two stages. In Stage 1 assembly you will complete the bare essentials of
BalloonSat including the BASIC Stamp, serial connection to the computer and the power supply section. This basic
configuration will be tested before moving on to Stage 2.
The following components are required for Stage 1:
□
□
□
□
□
□
□
BalloonSat printed circuit board
D1
1N5819 diode
C2
0.1 uf monoceramic capacitor
C5
0.1 uF monoceramic capacitor
J1
DB-9F pcb mount connector
J2
2-pin power connector and mating plug
U3
LM340 or 7805 +5 Voltage Regulator IC
□
□
□
□
□
□
24-pin DIP socket (for U1)
C1
47 uF electrolytic capacitor
C4
15 uF electrolytic capacitor
C10
0.1 uF monoceramic capacitor
JMP1 4X2 header and 4 shunts
U1
BS2P24 BASIC Stamp module
PUT YOUR SAFETY GLASSES ON!
Refer to the BalloonSat component layout diagrams and schematic diagrams.
Unassembled BalloonSat Printed Circuit Board (Component side view)
06/01/2007
BalloonSat Assembly Manual
5
BalloonSat with minimum required components (STAGE 1)
□ Socket for U1.
Install the 24-pin IC socket for U1 but DO NOT yet plug the BASIC Stamp module into its
socket. The BASIC Stamp module should be kept in its anti-static bag until needed. Make sure to orient the socket
correctly. Insert the socket into the printed circuit board and make sure that it is flat against the board before
soldering. Solder only two “corner” pins at first. Verify the orientation before soldering the other pins. Be careful
not to use too much solder.
□ Jumper JMP1
Jumper JMP1 is a 4X2 header with 0.1” pin-to-pin
spacing. The metal pins have a short side and a
long side. The short side (approximately 0.12”) are
soldered into the circuit board. The long side
(0.24”) stick up above the circuit board. In normal
operation shorting jumpers or shunts are placed
across the pins to complete the electrical circuit.
Some applications require removing one or more
jumpers.
06/01/2007
BalloonSat Assembly Manual
6
□ Connector J1.
Place the 9-pin right angle connector onto the
board. Make sure that all pins are protruding
through the board and that the connector is flat
against the board before soldering.
□ Connector J2
J2 has two pins in a plastic housing. The short
pin side is soldered into the printed circuit
board. The long pin side is where the mating
connector will attach.
□ Voltage Regulator U3
The orientation of voltage regulator U3 is very
important. The silk screen layer on the printed
circuit board shows a rectangular outline corresponding to the metal flange of the the component. Be sure to orient
the regulator properly before soldering.
Diode
Diode D1 is polarized! Make sure to orient it properly. The band indicating the cathode should match the band on
the printed circuit board component outline.
□ D1
1N5818 or 1N5819
Capacitors
Install the following electrolytic capacitors. Be sure to observe proper polarity!
□ C1
47 uF
□ C4
15 uF
Install the following monolithic ceramic capacitors. Polarity is not important but try to orient the components so that
their value markings are visible and not obscured by other parts. Solder into place and trim the leads.
□ C2
0.1uF
□ C5
0.1uF
□ C10 0.1uF
Testpoints
It is useful to have convenient testpoints for connecting to GND
and VCC. BalloonSat has three locations for testpoints, two for
GND and one for VCC. Each of the testpoints is marked by a
small rectangle on the silkscreen layer and has two plated-thru
holes. The two holes for each testpoint are electrically connected.
Pins may be soldered here or a loop of bare solid wire can be
used. The wire loop is convenient for attaching clips on
multimeter or oscilloscope leads.
06/01/2007
BalloonSat Assembly Manual
7
□ Testpoints (3 locations)
This completes the Stage 1 assembly of BalloonSat. Note that integrated circuit U1 (the BASIC Stamp module) is
NOT installed at this time. A few tests will be done before installing the BASIC Stamp.
Initial tests.
Prior to installing the BASIC Stamp micro-controller, you will verify
that the power supply section is functioning properly. BalloonSat
requires an external power source such as a laboratory DC power
supply capable of providing 9 to 15 VDC at approximately 100
milliamperes of current.
Use clip leads or fabricate a power cable to plug into J2 on the
BalloonSat board. It is suggested that you color code the leads so that
the GND or COMMON lead is BLACK and the + lead is RED.
Voltage checks
If the laboratory power supply has current limiting, set the
current limit to no more than 100 milliamperes and the
voltage to 9 volts. If the power supply is not adjustable, any
voltage from 9 to 15 VDC is suitable. Turn on the power
supply and measure the voltage at the + pin of J2 on
BalloonSat. This is the voltage input to BalloonSat and
should be between 9 and 15 volts. Next measure the voltage
at the VCC testpoint on BalloonSat. It should measure 5.00
volts, plus or minus 0.25 V, or between +4.75 and +5.25
VDC.
If the power supply has a current meter, it should measure
near zero. The current can also be measured by inserting an
appropriate multimeter set up for current measurement in
series between the power supply and BalloonSat.. Measured
current should be between 0 and 10 milliamperes. The only
load at this point of assembly is the internal circuitry of voltage regulator U3.
Measure the voltages at the following locations to verify that the expected voltage is present.
Pin No.
U1-21
U1-23
U2-8
U4-14
U5-2
U6-7
U7-1
Expected Value
5 V (VCC)
0 V (GND)
5V
5V
5V
5V
5V
Measured Value
Turn off the power supply and disconnect the power cable from J2 when the BalloonSat is not in use. This
completes the preliminary testing. If the voltage tests results were not as expected, visually inspect the BalloonSat
board for defective or missing solder joints or other construction or wiring errors.
06/01/2007
BalloonSat Assembly Manual
8
Operational Test
Install the BASIC Stamp BS2P24 module, U1, into its socket. You may need to gently form the leads to allow then
to fit easily into the socket. Be sure to identify pin 1 of the BASIC Stamp module. Refer to the photographs and
component layout diagram for the proper orientation of U1 in the 24-pin socket. Press the chip firmly into the
socket.
□ U1 BS2P24 Basic Stamp Module.
Place four shorting jumpers on JMP1. These configure the built-in serial port of the BASIC Stamp to communicate
with the serial port on the computer.
□ Shorting jumpers placed on JMP1 (4 positions on JMP1)
The final test for the Stage 1 BalloonSat is to verify communication with the BASIC Stamp Editor
Install the Parallax BASIC Stamp Editor on a suitable personal computer. The BASIC Stamp Editor can be
downloaded from Parallax, Inc. (www.parallax.com). Version 2.2 was current as of 08/17/2005.
Connect BalloonSat to the laboratory power supply and adjust for +9 VDC.
Connect a standard serial cable from an available serial port on the computer to the DB-9 connector on BalloonSat.
For computers without a standard serial port, you can use a USB-to-serial adapter. It should be installed and
configured according to the instructions accompanying the adapter.
Turn on the power supply, then
run the BASIC Stamp Editor.
From the Run pull down menu
select Identify.
You should see a window showing the type
of BASIC Stamp detected and its hardware
revision number.
06/01/2007
BalloonSat Assembly Manual
9
Programs can be written and downloaded to the BASIC Stamp. Type in the simple BASIC program example shown
below or write you may write your own program. Download and Run.
'Output a count to the debug screen each second
'{$STAMP BS2P}
'STAMP directive (specifies a BS2P)
cycles VAR Word
'Variable to store counted cycles.
cycles = 0
DEBUG CLS,"BalloonSat starting...",CR
Loop:
cycles = cycles + 1
PAUSE 1000
DEBUG "Cycle: ", DEC cycles,CR
GOTO Loop
EXAMPLE PROGRAM
You should see BalloonSat writing to the debug window each second with the incremented value of the variable
“cycles”
Although BalloonSat is functional at this point its capabilities are rather limited. Stage 2 assembly will complete
BalloonSat by adding several useful peripherals.
06/01/2007
BalloonSat Assembly Manual
10
Assembly – Stage 2
Complete the assembly of BalloonSat by installing the remaining components on the printed circuit board. Refer to
the schematic diagram, component layout diagram and photographs as needed. Check off the boxes below as
components are installed.
IC Sockets
Install integrated circuit sockets on the BalloonSat board. The silk screen outline on the board shows the proper
orientation for the notch in the socket. Solder one pin at each diagonally opposite corner and check that the socket is
flat against the board. If necessary, carefully reheat the corner pins while pressing the socket against the board. Be
careful not to burn your fingers! Do not insert the integrated circuits into the socket at this time.
□ U2 Socket (8-in)
□ U4 Socket (14-pin)
□ U5 Socket (8-pin)
□ U6 Socket (8-pin)
□ U7 Socket (8-pin)
Jumper Headers
BalloonSat can be configured for different options by placing suitable shorting jumpers or shunts at locations JMP1,
JMP2, and JMP3. You should already have soldered the 4X2 header into the board at location JMP1. Suitable
headers can now be installed at locations JMP2 and JMP3.
□ JMP2 (2-pin header)
□ JMP3 (3-pin header)
A shorting jumper can now be plugged onto the header at location JMP2. The presence or absence of a jumper
selects the A/D converter reference voltage. See the datasheets for the AD780 and ADC0834 for details.
A shorting jumper can be installed at location JMP3 to select the signal source for channel 3 of the A/D converter.
Channel 3 can be connected to either the on-board temperature sensor or to a user supplied source.
Capacitors
Install the following electrolytic capacitors. Be sure to observe proper polarity!
□ C7
□ C20 15 uF
15 uF
Install the following monolithic ceramic capacitors. Polarity is not important but try to orient the components so that
their value markings are visible and not obscured by other parts. Solder into place and trim the leads.
□ C6
0.1uF
□ C12 0.1uF
06/01/2007
□ C8
0.1uF
□ C11 0.1uF
□ C13 0.1uF
□ C21 0.1uF
BalloonSat Assembly Manual
□ C3
0.1uF
11
SIP Sockets and Resistor Networks
Single Inline Package (SIP) sockets should be installed at locations RN1 and RN2. If necessary, 10-pin SIP sockets
can be fabricated from a 20-pin machined pin DIP (dual inline package) socket by carefully cutting away the plastic
in the middle of the socket. Place the socket flat against the board and solder the end pins only. Verify that the
socket is flat against the board before soldering the other pins. Notice that the sockets are not polarized but the
resistor networks are. Pin 1 of the resistor networks are typically marked with a dot or band. This Pin 1 mark should
match the pin 1 designation on the printed circuit board, a small square on the component symbol.
□ SIP Socket at RN1
□ Resistor Network RN1 (10K)
□ SIP Socket at RN2
□ Resistor Network RN2 (10K)
Resistors
R1, R2, R3 and R4 are mounted vertically to save space on the printed circuit board. Bend one resistor lead taking
care not to damage the body of the resistor. Insert into board and solder.
□ R1
□ R3
□ R2
□ R4
2.2K
2.2K
2.2K
2.2K
Resistors R5 and R6 are mounted flat against the printed circuit as
shown by the silkscreen component outline.
□ R5
□ R6
1.2K
6.2K
LED’s DS1-DS4
Orient the LED cathode (flatted side or short lead) towards the edge of
the board. The anode (long lead) is next to the associated resistor. Try to mount the LED’s “neatly”, all the same
height and aligned with each other.
□ DS1 LED
□ DS2 LED
□ DS3 LED
□ DS4 LED
Variable Resistor
Place variable resistor RV1 flat against the circuit board. Solder only one pin. Make sure the part is flat against the
board, then solder the remaining pins. Orient RV1 so that the screwdriver adjustment shaft matches the symbol on
the silkscreen component outline.
□ RV1
500 ohm
Crystal Resonator
Mount and solder crystal Y1. The wire leads are delicate, so handle and solder with caution. The body of the crystal
should be oriented flat against the circuit board as shown in the photograph above.
□ Y1
32.768kHz
06/01/2007
BalloonSat Assembly Manual
12
Integrated Circuits
The BASIC Stamp module U1 should already be in its socket. Voltage regulator IC U3 was installed in Stage 1. The
remaining IC’s can now be installed into their respective sockets. Refer to the BalloonSat schematic and layout
diagrams for component locations. All integrated circuits must be properly oriented.
□ U2
24LC64
□ U4
ADC0834
□ U5
AD780
□ U6
AD820 (or OP07)
□ U7
DS1302
Optional Components
BalloonSat provides space for connecting external electronics at locations PL, PH and P2. The type of connection
will depend upon the requirements for your application. Connections could be made by soldering wires directly to
the board or by mounting suitable connectors at these locations.
Voltage Checks
Repeat the voltage checks that were done at the Stage 1 assembly.
Pin No.
U1-21
U1-23
U2-8
U4-14
U5-2
U6-7
U7-1
Expected Value
5 V (VCC)
0 V (GND)
5V
5V
5V
5V
5V
Measured Value
Verify that voltage reference U5 is operating properly. Pin 6 of U5, an AD780 is the reference output.
Measure the voltage at U5 pin 6 with respect to GND. With jumper JMP2 open, the voltage at U5 pin 6 should be
2.50 VDC.
Place a shorting jumper across JMP2. Measure the voltage at U5 pin 6 with respect to GND. The voltage at U5 pin 6
should now be 3.00 VDC.
Pin No.
U5-6 with JMP2 open
U5-6 with JMP2 shorted
Expected Value
2.50 VDC
3.00 VDC
Measured Value
U5 pin 3 is the temperature transducer output. The voltage level measured with a high input impedance digital
multimeter (DMM) will be the ambient temperature (in degrees Kelvin) x 2 mv/degree. At room temperature this
will be approximately 0.57 VDC.
06/01/2007
BalloonSat Assembly Manual
13
Pin No.
U5-3
Expected Value
About 0.57 VDC
Measured Value
If you warm or cool U5, the voltage at U5 pin 3 should change accordingly.
This completes the Stage 2 assembly of BalloonSat.
06/01/2007
BalloonSat Assembly Manual
14
BalloonSat bill of materials
QTY Reference Designator
1
10
3
1
4
1
1
1
1
1
1
1
1
1
2
1
1
1
1
1
1
1
1
1
1
3
1
1
6
1
2
Description
C1
C2,C3,C5,C6,C8,C10,C11,C12,C13,C21
C4,C7,C20
D1
DS1,DS2,DS3,DS4
J1
J2
JMP1
JMP2
JMP3
R1,R2,R3,R4
R5
R6
RN1,RN2
RV1
P2
PCB
U1
U2
U3
U4
U5
U6
U7
Y1
06/01/2007
47 uF 25wvdc radial lead electrolytic, 3.5mm lead spacing
0.1uF monoceramic, radial 0.1" lead spacing
15 uF 10WVDC electrolytic capacitor, radial 2mm lead spacing
1N5819 Schottky diode, DO-35 package
Red LED 0.1 lead spacing
DB-9F connector, pcb mount 09 MSl RCPT RA 318
ED1660
Mate for J2, p/n ED1613
4 X 2 pin header 0.1" pin spacing
1 X 2 pin header
1 X 3 pin header
2.2K 1/4 W 5% axial lead resistor
1.2K 1/4W 5% axial lead resistor
6.2K 1/4W 5% axial lead resistor
10K Resistor network, SIP10 package
500 ohm variable resistor 3299W package (see Activity P4)
2 x 10 pin header or 2 X 10 shrouded header – optional component
Printed circuit Board, LSU p/n BSAT12
BS2P24 BASIC Stamp module, DIP24 package
24LC64 Integrated Circuit, EEPROM 64k bit, DIP8 package
LM340 or 7805 Integrated Circuit, Voltage regulator fixed +5V, TO-220 package
ADC0834 Integrated Circuit, 4 channel ADC, DIP14 package
AD780 Integrated Circuit, Voltage reference IC, DIP 8 package
AD820 or OP-07 IC, operational amplifier, DIP 8 package
DS1302N
Socket, IC DIP8
Socket, IC DIP14
Socket, IC DIP24
Shunt, 0.1"
Crystal resonator 32.768kHz
Socket, SIP10
BalloonSat Assembly Manual
15
BalloonSat Schematic Diagram
06/01/2007
BalloonSat Assembly Manual
16
BalloonSat Component Placement Diagram (Silk Screen Overlay)
BalloonSat Copper Layers (Red = Top Copper; Blue = Bottom Copper)
06/01/2007
BalloonSat Assembly Manual
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