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TECHNICAL INFORMATION
Class-T Digital Audio Amplifier Evaluation Board using Digital Power
Processing (DPPTM) Technology
EB-TA2022
2 Channel TA2022 Demo Board
February 2001, for Rev.1.5 & Rev.1.6 Boards
General Description
The EB-TA2022 demonstration board is an easy to use platform, which demonstrates the features of the
TA2022 integrated digital audio power amplifier from Tripath Technology. The evaluation board includes
an output relay, a DC offset servo, and a DC protection circuit.
Features
Benefits
Ø
Ø
Ø
Ø
Ø
Ø
2 x 90W continuous output
power @ 0.1% THD+N, 4Ω, ±31V.
2 x 100W continuous output
power @ 1.0% THD+N, 4Ω, ±31V.
2 x 60W continuous output
power @ 0.1% THD+N, 8Ω, ±35V.
150uV A-weighted output noise voltage,
Av = 18.
Outputs short circuit protected.
Ø
Ø
Quick, easy evaluation and testing of the
TA2022 amplifier.
No external power MOSFETs.
Ready to use in many applications:
Ø 2 channel stereo systems.
Ø Powered 2.1 speaker systems.
EB-TA2022, Rev. 1.5 and Rev. 1.6
1
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TECHNICAL INFORMATION
OPERATING INSTRUCTIONS
Power Supply Description
There are two external power supplies required to operate this board: V+, and V- (see Figures 1 and
2). Minimum and maximum supply voltages are ±20V and ±36V, respectively, depending on the load
impedance. It is not recommended that the EB-TA2022 be operated above ±31V when driving 4 ohm
loads, single ended, as the internal current limit circuit may activate, causing the amplifier to mute.
With load impedances of 5 ohms or greater, the EB-TA2022 can safely be operated up to the TA2022
recommended maximum supply voltage of ±36V.
All output and power supply connections are made using 0.156” spaced, 0.045” diameter headers
(Male: Molex 26-48-1XX2, Female: Molex 09-50-8XX1).
Figure 1 shows the proper supply configuration for the EB-TA2022 Demoboard.
Vs
- +
0V(Black)
Gnd
Vs
V+(Yellow)
V-(Orange)
Vo2
Gnd
- +
Vo1
TA2022
In1
In2
Mute
Audio
Source
Figure 1
EB-TA2022, Rev. 1.5 and Rev. 1.6
2
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TECHNICAL INFORMATION
Connector
Power Supply
JP3 (yellow)
V+
JP3 (black)
0V
JP3 (orange)
V-
Table 1
Input Connections
The audio inputs use industry standard RCA connectors and are marked In1 and In2. The input can
be a test signal or music source. The TA2022 input stage operates from a single 5V supply and the
inputs are AC-coupled to remove the 2.5V DC bias. To eliminate turn on/off pops caused by charging
the DC blocking capacitors, you must mute the amplifier before plugging in, or removing, the input
cable.
Output Connections
The audio outputs are provided through connector JP2, a single 0.156” spaced, 0.045” diameter
header (Male: Molex 26-48-1XX2, Female: Molex 09-50-8XX1). A banana plug terminated, four-wire
harness is provided with the EB-TA2022. The TA2022 can be operated as a two-channel singleended amplifier, bridged mono output amplifier or with a passive crossover for a 2.1 channel
application (refer to Application Note 13). Outputs can be passive speaker(s), or test measurement
equipment and a resistive load with an impedance of at least 4 ohms (8 ohm bridged).
TA2022 Control Circuitry
The user can mute the EB-TA2022 amplifier with the SPDT switch, SW2. See Mute Control under
Amplifier Section.
EB-TA2022, Rev. 1.5 and Rev. 1.6
3
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TECHNICAL INFORMATION
EB-TA2022 Board
Power
V- 0V V+
Outputs
Vo2
Gnd
Gnd
Vo1
HMUTE
LED
In1
In2
Mute
Figure 2
Circuit Discussion
Amplifier Section
Schematic 1 shows the amplifier section of the EB-TA2022. For the most part, this is the circuitry that
is inside the “boundary of holes” on the EB-TA2022 and represents the near minimal circuitry for
operation of the TA2022. Extra circuitry includes EMI precautions (the 100pF / 1,000pf capacitors at
all inputs and outputs), output relays and DC offset correction servos, and the HMUTE LED. The 5V
generation circuitry, D5 and Q1, can be eliminated if the designer supplies 5V externally. The
following is a discussion of the EB-TA2022 demo board amplifier section and the output-offset voltage
correction and relay sections.
EB-TA2022 Basic Amplifier Operation
The TA2022 has 3 major operational blocks: the signal processor, the MOSFET driver and the power
MOSFETs. The signal processor is a 5V CMOS block that amplifies the audio input signal and
EB-TA2022, Rev. 1.5 and Rev. 1.6
4
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TECHNICAL INFORMATION
converts the audio signal to a switching pattern. The switching pattern is spread spectrum with a
typical idle switching frequency of 650 kHz. The switching patterns for the two channels are not
synchronized and the idle switching frequencies are set to differ by at least 40 kHz to avoid increasing
the audio band noise. The idle switching frequency difference is accomplished by offsetting the
feedback capacitors, C13 and C14, for each channel. In the EB-TA2022, C13 is 560pf for channel 1
and C14 is 330pf for channel 2, which are typical values for the feedback capacitors.
The MOSFET driver has a simple switching power supply integrated to generate the VN10 bootstrap
supply. Special floating or bootstrapped supplies, VBOOT1 and VBOOT2, are used to power the
high side MOSFET drivers. VN10 must be stable (regulated) at 10V to 12V above VNN. The VN10
circuitry in the EB-TA2022 typically produces 11V above VNN. In order to help eliminate noise in the
VN10 supply, decoupling capacitors C28, C4 and C5 are used.
The power MOSFETS are N-channel devices configured in half-bridges and are used to supply power
to the audio load. The outputs of the power MOSFETS, OUT1 and OUT2, are low pass filtered using
inductors L2 and L3 to remove the high frequency switching pattern.
TA2022 Amplifier Gain
The TA2022 amplifier gain is the product of the input stage gain and the modulator gain. Refer to the
sections, Input Stage Design, and Modulator Feedback Design, for an explanation on how to
determine the external component values.
AVTA2022 = AVINPUTSTAGE * AVMODULATOR
AVTA2022
_ RF x
RI
(
)
RFBC * (RFBA + RFBB) + 1
RFBA * RFBB
For the EB-TA2022;
RI (R1, R3) = 20kΩ
RF (R26, R27) = 20kΩ
RFBA (R12, R15) = 1kΩ
RFBB (R23, R24) = 1.1kΩ
RFBC (R8, R25) = 9.1kΩ
AVTA2022
_ 20kΩ x
20kΩ
(
9.1kΩ * (1kΩ + 1.1kΩ) + 1
1kΩ * 1.1kΩ
)
= 18.37 V/V
EB-TA2022, Rev. 1.5 and Rev. 1.6
5
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TECHNICAL INFORMATION
Input Stage Design
As shown in Figure 3, the input stage of the EB-TA2022 is set as a constant gain, inverting amplifier.
OAOUT1
C17
3.3uf
R1
20K
TA2022
2
V5
R26
20K
INV1
INPUT1
+
BIASCAP
AGND
V5
+
INV2
C15
3.3uf
R3
20K
R27
20K
-
AGND
OAOUT2
INPUT2
Figure 3. Input Stage
Input Capacitor Selection
Input capacitors C15 and C17 are calculated once a value for the input resistors R1 and R3 has been
determined. R1, C17 and R3, C15 determine the input low frequency poles (Fp) for channel 1 and
channel 2, respectively. Typically, this pole is set below 10Hz. C15 and C17 are calculated using:
CI =
1
2πFp x RI
For For the EB-TA2020;
CI = C15, C17
RI = R1, R3
FP= 2.4 Hz
RI = 20KΩ
CI =
1
= 3.3 µF
2π (2.4Hz) x (20KΩ)
EB-TA2022, Rev. 1.5 and Rev. 1.6
6
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TECHNICAL INFORMATION
Modulator Feedback Design
The modulator converts the signal from the input stage to the high-voltage output signal. The
optimum gain of the modulator is determined from the maximum allowable feedback level for the
modulator and maximum supply voltages for the power stage. Depending on the maximum supply
voltage, the feedback ratio will need to be adjusted to maximize performance. The values of
feedback network R12, R15, R23, R24, R8, and R25 (see figure 4) define the gain of the modulator
for channel 1 (see explanation below). Once the feedback network values are chosen, based on the
maximum supply voltage, the gain of the modulator will be fixed even as the supply voltage fluctuates
due to current draw.
For the best signal-to-noise ratio and lowest distortion, the maximum modulator feedback voltage
should be approximately 4Vpp. This keeps the gain of the modulator as low as possible, and still
allows headroom so that the feedback signal does not clip the modulator feedback stage.
Figure 4 shows how the feedback from the output of the amplifier is returned to the input of the
modulator. The input to the modulator (FBKOUT1/FBKGND1 for channel 1) can be viewed as inputs
to an inverting differential amplifier. Resistors R12, R15, R23 and R24 bias the feedback signals to
approximately 2.5V. Resistors R8 and R25 scale the output signals down to 4Vpp.
½ TA2022
V5
R12
1K
R15
1K
R8
9.1K
Processing
FBKOUT1
OUT1
&
FBKGND1
OUT 1 GROUND
Modulation
R25
9.1K
R23
1.1K
R24
1.1K
AGND
Figure 4. Modulator Feedback
EB-TA2022, Rev. 1.5 and Rev. 1.6
7
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TECHNICAL INFORMATION
The modulator feedback resistors are:
VPPmax, (VNNmax) = 36V
R12, R15 = 1kΩ (User specified)
R23, R24 = R12 x VPPmax
(VPP – 4)
R8, R25 = R12 x VPP
4
= 1kΩ x 36V = 1.125kΩ, Use 1.1kΩ
(36V – 4V)
= 1kΩ x 36V
4
= 9kΩ, Use 9.1kΩ
The Note: The above equations assume that VPP = |VNN|
Av – MODULATOR = R8 x (R12 + R23) + 1 = 9.1kΩ x (1kΩ + 1.1kΩ) + 1 = 18.37 V/V
(R12 x R23)
1kΩ x 1.1kΩ
Mute Control
To ensure proper device operation, including minimization of turn on/off transients that can result in
undesirable audio artifacts, Tripath recommends that the EB-TA2022 be muted prior to power up or
power down of the 5V supply.
If turn-on and/or turn-off noise is still present with the EB-TA2022 board, the cause may be other
circuitry external to the EB-TA2022. While the TA2022 has circuitry to suppress turn-on and turn-off
transients, the combination of power supply and other audio circuitry with the EB-TA2022 in a
particular application may exhibit audible transients. One solution that will completely eliminate turnon and turn-off pops and clicks is to use a relay to connect/disconnect the TA2022 from the speakers
with appropriate timing during power on/off.
EB-TA2022 Output Capability
The EB-TA2022 can output 100 watts into a 4ohm load at 1% THD+N from ± 31V supplies. The
maximum amplifier output power is determined by a number of factors including the TA2022 junction
temperature, the load impedance and the power supply voltage.
Tripath does not recommend driving loads below 4 ohm, as the EB-TA2022 amplifier efficiency will be
seriously reduced and the amplifier may prematurely current limit.
EB-TA2022, Rev. 1.5 and Rev. 1.6
8
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TECHNICAL INFORMATION
Output Filter Design
Tripath amplifiers generally have a higher switching frequency than PWM implementations allowing
the use of higher cutoff frequency filters, reducing the load dependent peaking/drooping in the 20kHz
audio band. This is especially important for applications where the user may attach any speaker to
the amplifier (as opposed to a system where speakers are shipped with the amplifier), since speakers
are not purely resistive loads and the impedance they present changes over frequency and from
speaker model to speaker model. In the EB-TA2022, an RC network, or “zobel” (R10 & C18, and
R13 & C20) is used at the filter output to control the impedance “seen” by the TA2022. The TA2022
nd
works well with a 2 order, 80kHz LC filter with L2 & L3 = 10uH, C16 & C19 = 0.22uF, R10 & R13 =
6.2 ohm, and C18 & C20 = 0.22uF.
Output inductor selection is a critical design step. The core material and geometry of the output filter
inductor affects the TA2022 distortion levels, efficiency, power dissipation and EMI output. The
inductor should have low loss at 650kHz with 72Vpp. The EB-TA2022 uses a T94-2 iron powder
core, wound to 11.3uH with 19awg wire (38 turns). For more information on other type filter
inductors, see the TA-2022 Audio Amplifier Datasheet.
Protection Circuits
The EB-TA2022 is guarded against over-current and over/under-voltage conditions. If the TA2022
device goes into an over-current or over/under-voltage condition, the HMUTE goes to a logic HIGH
indicating a fault condition. When this occurs, the amplifier is muted, all outputs are TRI-STATED,
and will float to approximately 2.5VDC. For more information on TA2022 fault conditions, see the
TA2022 Audio Amplifier Datasheet.
Fault LED Indicator
The HMUTE (pin 32) is a 5V logic output that indicates various fault conditions within the device.
These conditions include: over-current, over-voltage and under-voltage. The HMUTE output directly
drives LED D4, through a series 2 kΩ resistor (R4).
Output-Offset Voltage Correction and Relay Section
The output-offset voltage in the EB-TA2022 is automatically nulled using a “DC servo”. Schematic 2
shows the circuitry used to eliminate the output-offset (DC servo) and to control the output relay.
The inverting integrators, U2A and U2B, integrate the output offset (from Vo1a and Vo2a) and feed
the result into the non-inverting feedback input, FBKGND1(2), of the amplifier. While the integrator
output will nominally be between 2.3V and 2.7V, the initial output, before any integration, is
EB-TA2022, Rev. 1.5 and Rev. 1.6
9
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TECHNICAL INFORMATION
approximately 0.5V. This causes a large offset, so a relay is used to disconnect the amplifier outputs
from the speakers while the offset is corrected. The LM358 does not handle the 600+ kHz amplifier
output ripple well, so the amplifier output, Vo1a(Vo2a) is filtered by R52 and C46 (R54 and C47)
before being integrated.
The relay has two control signals: HMUTE and abnormal output offsets sensed by the window
comparator U3. The relay control, Q2, will turn on slowly due to R42, R53 and C44, but will turn off
quickly since C44 is actively discharged by U3 or Q4. D7 serves to limit the voltage on the gate of
Q2, thereby limiting the current through Q2 and the current through K1. K1 is a 24V relay, but the
voltage at V+ can vary between 20V and 36V, so the relay is driven by approximately 20mA,
independent of V+.
The supply voltage, V+, can exceed the maximum operating voltage for U2 and U3, so Vcomp is a
13V supply (via R40 (3K resistor) and D6 (13V zener)), which is used to power U2 and U3. The two
voltages, 1.5V and 4V, for the window comparator are also derived from Vcomp.
Layout Discussion
Component Layout
The TA2022 is a power (high current) amplifier that operates at relatively high switching frequencies.
The output of the amplifier switches between the VPP and VNN at high speeds while driving large
currents. This high-frequency digital signal is passed through an LC low-pass filter to recover the
amplified audio signal. Since the amplifier must drive the inductive LC output filter and speaker loads,
the amplifier outputs can be pulled above the supply voltage and below ground by the energy in the
output inductance. To avoid subjecting the TA2022 to potentially damaging voltage stress, it is critical
to have a good printed circuit board layout. It is recommended that the EB-TA2022 evaluation board
be used for all applications and only be deviated from after careful analysis of the effects of any
changes.
In order to achieve the best performance and reliability of the TA2022, the EB-TA2022 evaluation
board was designed with the following layout considerations in mind.
The following components are important to place near their associated TA2022 pins and are ranked
in order of layout importance, either for proper device operation or performance considerations.
1. Capacitors C38 and C39 provide high frequency bypassing of the amplifier power supplies
and serve to reduce spikes across the supply rails. The bypass capacitors are within 1/8”
(3mm) of the VNN (8,9) and VPP (4,12) pins. Please note that both VNN1 and VPP1, as well
as VNN2 and VPP2, are decoupled separately. In addition, the voltage rating for C38 and
C39 is 100V, as this capacitor is exposed to the full supply range, VPP-VNN.
EB-TA2022, Rev. 1.5 and Rev. 1.6
10
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TECHNICAL INFORMATION
2. D8 and D9 are fast recovery PN junction diodes that minimize undershoots of the outputs
with respect to power ground during switching transitions and abnormal load conditions such
as output shorts to ground. For maximum effectiveness, these diodes are located close to
the output pins and returned to their respective VNN1 (2).
3. C13 and C14 are the feedback capacitors, which remove very high frequency components
from the amplifier feedback signals and lower the output switching frequency by delaying the
feedback signals.
4. C4 provides high frequency bypassing for the VN10 (pin 2). Very high currents are present
on these supplies.
5. C8 and C42 filter the bootstrap supplies for channel 1 and channel 2 respectively. These
capacitors should be located as close to the TA2022 device as possible.
6. C28 filters the feedback signal, VN10FDBK, for the hysteretic VN10 buck converter. The
feedback signal is noise sensitive and care should be taken with the connection of C28 to
VNN.
7. D1 is the flywheel diode for the VN10 buck converter and prevents VN10SW (pin 5) from
going more than one diode drop below VNN.
In general, to enable placement as close to the TA2022, and minimize PCB parasitics, the capacitors
listed above are surface mount and located on the “solder” side of the board.
Some components are not sensitive to location but are very sensitive to layout and trace connection.
1. To maximize the damping factor and reduce distortion and noise, the modulator feedback
connections are routed directly to the inputs of the output inductors L2 and L3.
2. The output filter capacitors C16 and C19, and zobel capacitors C18 and C20, should be star
connected with the load return and the output ground feedback signal should be taken from
the star point. This is suggested by the routing on the EB-TA2022 schematic, but, for
space/layout reasons, this was not fully implemented on the EB-TA2022 demonstration
board.
3. The modulator feedback resistors R11, R5, R12, R15, R20, R22, R23, R24, R7, R8, R21 and
R25 are grounded and attached to 5V together. These connections serve to minimize
common mode noise via the differential feedback.
EB-TA2022, Rev. 1.5 and Rev. 1.6
11
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TECHNICAL INFORMATION
Grounding Layout
Proper grounding techniques are required to maximize the TA2022 functionality and performance.
Parametric parameters such as THD+N, Noise Floor and Crosstalk can be adversely affected if
proper grounding techniques are not implemented on the PCB layout. The following discussion
highlights the grounding layout of the EB-TA2022 as well as general “audio system” design rules.
The TA2022 is divided into two sections: the input section, which spans pin 15 through pin 32, and
the output (high power) section, which spans pin 1 through pin 14. On the EB-TA2022 evaluation
board, the ground is divided into two distinct sections, one for the input and one for the output. To
minimize ground loops and keep the audio noise floor as low as possible, the input and output
grounds are connected at a single point. The single point connection is through ferrite bead L6.
The analog grounds, pin 15 and pin 20 are connected locally at the TA2022 for proper device
functionality. The EB-TA2022 uses an analog ground plane to minimize the impedances between pin
15 and pin 20 as well as the other analog ground connections, such as the V5 supply bypassing, and
feedback divider networks. The ground for the V5 power supply is connected directly to pin 20.
Additionally, any external input circuitry such as preamps, or active filters, should be referenced to pin
20.
For the power section, Tripath has traditionally used a “star” grounding scheme. Thus, the load
ground returns and the power supply decoupling traces are routed separately back to the power
supply. In addition, any type of shield or chassis connection would be connected directly to the
ground star located at the power supply. These precautions both minimize audible noise and
enhance the crosstalk performance of the EB-TA2022.
The EB-TA2022 incorporates a differential feedback system to minimize the effects of ground bounce
and cancel out common mode ground noise. As such, the feedback from the output ground for each
channel is properly sensed. This is accomplished by connecting the output ground “sensing” trace
directly to the star formed by the output ground return, output capacitors, C16 and C19, and the zobel
capacitors, C18 and C20.
Pin 3, VN10GND is used for the VN10 buck converter in the TA2022. In the EB-TA2022, pin 3 is
connected to the main power supply ground plane without any loss in functionality or reduction of
performance.
Heat Sink Thermal Characteristics
In most applications it will be necessary to fasten the TA2022 to a heat sink. The determining factor
for heat sink consideration is the 150°C maximum junction temperature, TJMAX, cannot be exceeded,
as specified by the following equation:
EB-TA2022, Rev. 1.5 and Rev. 1.6
12
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TECHNICAL INFORMATION
PDISS = (TJMAX – TA )
θJA
where;
PDISS = maximum power dissipation
TJMAX = maximum junction temperature of TA2022
TA = operating ambient temperature
θJA = junction-to-ambient thermal resistance
θJA = θJC + θCS + θSA
Example:
What size heat sink is required to operate the TA2022 at 80W per channel continuously in a 70ºC
ambient temperature?
PDISS is determined by:
Efficiency = η =
PDISS (per channel) =
POUT
POUT
=
PIN
POUT − PDISS
POUT - POUT
η
=
90
0.85
- 90 = 15.88 W
Thus, PDISS for two channels = 31.76
W
θJA = (TJMAX – TA ) = 150 – 70 = 2.52 °C/W
PDISS
31.76
The θJC of the TA2022 is 1.0°C/W, so a heat sink with a θSA of 1.32 °C/W is required for this
example (assuming a θCS = 0.2°C/W). In actual applications, other factors such as the average PDISS
with a music source (as opposed to a continuous sine wave) and regulatory agency testing
requirements will determine the size of the heat sink required.
The EB-TA2022 uses a Wakefield Engineering Type 2018 heat sink extrusion, with a θSA of 2.3°C/W
per 3 inch length. The EB-TA2022 heat sink is cut to a length of 1.75 inches, and has a volume of
7.46 cubic inches. Using the Wakefield Engineering thermal resistance versus heat sink volume
graphs, the thermal resistance of the EB-TA2022 heat sink is 3.5°C/W. Although the heat sink
provided on the EB-TA2022 is not sufficient to run the demo board at 80 watts continuous output
power (using the example above), it is adequate for normal listening levels.
EB-TA2022, Rev. 1.5 and Rev. 1.6
13
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TECHNICAL INFORMATION
Performing Measurements on the EB-TA2022
The TA2022 operates by generating a high frequency switching signal based on the audio input. This
signal is sent through a low-pass filter that recovers an amplified version of the audio input. The
frequency of the switching pattern is spread spectrum in nature and typically varies between 100kHz
and 1MHz, which is well above the 20Hz – 20kHz audio band. The pattern itself does not alter or
distort the audio input signal, but it does introduce some inaudible components.
The measurements of certain performance parameters, particularly noise related specifications such
as THD+N, are significantly affected by the design of the low-pass filter used on the output as well as
the bandwidth setting of the measurement instrument used. Unless the filter has a very sharp roll-off
just beyond the audio band or the bandwidth of the measurement instrument is limited, some of the
inaudible noise components introduced by the TA2022 amplifier switching pattern will degrade the
measurement.
One feature of the TA2022 is that it does not require large multi-pole filters to achieve excellent
performance in listening tests, usually a more critical factor than performance measurements.
Though using a multi-pole filter may remove high-frequency noise and improve THD+N type
measurements (when they are made with wide-bandwidth measuring equipment), these same filters
degrade frequency response. The EB-TA2022 Evaluation Board has a simple two-pole output filter
with excellent performance in listening tests.
(See Application Note 4 for more information on bench testing)
CONTACT INFORMATION
For more information on Tripath products, visit our web site at: www.tripath.com
TRIPATH TECHNOLOGY, INC.
3900 Freedom Circle, Suite 200
Santa Clara, California 95054
408-567-3000
EB-TA2022, Rev. 1.5 and Rev. 1.6
14
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4
1
HMUTE
FBKOUT1
HMUTE
R4
2K
32
FBKOUT2
FBKGND1
31
30
FBKGND2
29
BIASCAP
28
OAOUT2
INV2
27
26
INV1
OAOUT1
MUTE
25
24
23
AGND
V5
22
21
VNSENSE
REF
VPSENSE
20
19
18
V5
17
VN10FBK
AGND
15
VBOOT1
2
U1
14
VPP1
13
OUT1
VNN1
VNN2
HO1COM
12
11
10
9
OUT2
8
7
VN10SW
6
VN10GND
VPP2
5
4
3
VN10
VBOOT2
2
1
HO2COM
tornado_32p_zip_6
TA2022
D
3
16
5
D
2
D8
MUR120
C38
0.1uF;100V
C5
100uF;35V
R34
250
1
C
2
PGnd V+
2
D2
11DQ09
C11
47uF;16v
VN10FDBK
1
2
C28
0.1uF
VC4
0.1uF
VPSENSE
VNSENSE
D9
MUR120
PGND
5V
C1
0.1uF;100V
D4
LED
C24
100pF
D1
11DQ09
R18
1k
1
VN10FDBK
2
1
L1
100uH
R30
232k
R14
232k
R3
20K
C39
0.1uF;100V
V-
V+
MUTE
C3
0.1uF
C9
0.1uF
1
2
3
4
R2
10k
C23
No Stuff
HEADER 4
C12
47uF;16v
R7
9.1k
J2
R1
20K
5V
R11
1k
C8
0.1uF
C15
3.3uF;25V
J3
GA_STAR_EMI
1
D3
11DQ09
R36
1k
PGND
R19
8.2k
R33
250
V-
GA_STAR_EMI
R27
20k
R26
20k
R5
1k
R12
1k
R9
10k
C2
No Stuff
C17
3.3uF;25V
4
3
2
1
R35
1k
HEADER 4
R15
1k
C
R8
9.1k
C42
0.1uF
1
2
3
4
R29
NO STUFF
R16
NO STUFF
3
Vo1b
FBKGND2
C13
560pF
Vo2b
Vo2a
Outputs
R13
6;2W
R10
6;2W
R20
1.1k
L3
11.3uH
C19
0.22uF;50V
R22
1.1k
R6
NO STUFF
3
1
Vo1a
C14
330pF
2
FBKGND1
R28
NO STUFF
1
L2
11.3uH
JP2
R25
9.1k
2
R21
9.1k
R23
1.1k
R24
1.1k
B
B
C18
0.22uF;50V
PGnd
C33
1000pF
C16
0.22uF;50V
C6
100pF
SW2
3
2
1
C20
0.22uF;50V
C34
1000pF
5V
Mute
C35
100pF
SPDT;Mute Switch
PGnd
CON4
J7
+
C21
100uF;50V
JP3
A
1
2
3
C31
1000pF
1
2
In
Gnd
Q1
LM7805CT
Out
5V
D5
1N4736A
C22
0.1uF;50V
C10
100pF
CON1
PGnd
1
PGnd
J8
CON2
1
2
3
4
1
CON4
CON3
C25
0.1uF;50V
Title
1
TA2022 Demo Board Ver. 1.5
STANDOFF
Size
B
Date:
4
A
Tripath Technology Inc.
STANDOFF
V-
5
PGnd
GA_STAR_EMI
STANDOFF
HEADER 3
+
C26
100uF;50V
R17
STANDOFF
CON4
PGnd
C32
1000pF
1
1
2
3
4
V+
L6
FB
3
Browse our extensive range of Tripath and other audio parts at
www.profusionplc.com
2
Document Number
Rev
Schematic 1
Monday, November 13, 2000
Sheet
1
1
1.5
of
3
5
4
3
2
1
C43
3.3uF
U2A
LM358
4
2
-
3
FBKGND1
C48
0.1uF
D
V+
V+
1
VCOMP
1
VCOMP
R43
80k
C27
0.1uF
7
+
6
PGND
R42
200k
-
R45
25k
U3A
LM339
PGND
1
3
Q3
2N7000
+
4
-
2
Vo1a
K1
R55
300
1
R44
250k
2
1
2
3
D7
1N5235
1
3
2
2
U3B
LM339
2
1
7
Vo2a
3
8
Vo1a
5
Vo2b
6
Q2
2N7000
4
Vo1b
DPDT RELAY
12
3
C
5
Q5
2N3906
R56
50K
VCOMP
R48
35k
R47
15k
D10
1n4148
1
12
PGND
2
D6
1N5243
2
R52
50k
R40
3k
VCOMP
8
C46
0.1uF
R39
100K
R38
10k
1
+
D
PGND
3
R37
50k
C44
22uF, 10V
PGND
R53
100k
C
3
PGND
2
HMUTE
VCOMP
3
Vo2a
+
8
-
PGND
U3C
LM339
14
12
9
1
Q4
2N7000
PGND
C45
3.3uF
VCOMP
3
R54
50k
11
+
B
8
R51
100K
12
4
5
C47
0.1uF
B
-
R50
10k
PGND
7
FBKGND2
+
6
-
R49
50k
10
PGND
U2B
LM358
U3D
LM339
13
VCOMP
PGND
A
A
Title
OFFSET CORRECTION & RELAY CIRCUIT
Size
B
Date:
5
4
Document Number
Monday, November 13, 2000
3
Browse our extensive range of Tripath and other audio parts at
www.profusionplc.com
Rev
1.5
SCHEMATIC 2
Sheet
2
2
of
3
1
TA2022 Demo Board Ver. 1.5
Revision: 1.5
Revised: 11/13/2000
Bill Of Materials
Item Quantity
Reference
Part
Digikey Part #
Manufacturers Part# (Package)
______________________________________________________________________________________________________________________________
______
1
9
C8,C27,C42,C46,C47,C48 0.1uF;50V
PCC1864CT-ND
Panasonic ECJ-2VF1H1042(SMT 0805)
C3,C9,C28
2
2
C38,C39
0.1uF;100V
Capsco-NMC1210X7R104K100TRPLP117501(SMT 1210)
3
2
C23,C2
No Stuff
4
4
C6,C10,C24,C35
100pF;50V
PCC101CGCT-NC
Panasonic ECJ-2VC1H101J(SMT 0805)
5
4
C31,C32,C33,C34
1000pF;50V
PCC102CGCT-ND
Panasonic ECU-V1H102JCX(SMT 0805)
6
1
C13
560pF;50V
PCC561BNCT-ND
PANASONIC ECU-V1H561KBN(SMT 0805)
7
1
C14
330pF;50V
PCC331BNCT-ND
PANASONIC ECU-V1H331KBN(SMT 0805)
8
4
C17,C15,C43,C45
3.3uF;25V
P6626-ND
Panasonic ECE-A25Z3R3(Thru-Hole)
9
4
C16,C18,C19,C20
0.22uF;50V
P4667-ND
Panasonic ECQ-V1H224JL(Thru-Hole)
10
2
C26,C21
220uF;50V
P10325-ND
Panasonic ECA-2AHG101(Thru-Hole)
11
3
C4,C22,C25
0.1uF;50V
P4525-ND
Panasonic ECQ-V1H104JL(Thru-Hole)
12
1
C44
22uF,6.3V
P955-ND
Panasonic ECE-A0JKS220(Thru-Hole)
13
1
C1
0.1uF;100V
P4725-ND
Panasonic ECQ-V1104JM(Thru-Hole)
14
1
C5
100uF;35V
P5165-ND
Panasonic ECA-1CM101(Thru-Hole)
15
2
C11,C12
47uF;16v
P810-ND
Panasonic ECE-A1CKA470(Thru-Hole)
16
3
D1,D2,D3
11DQ09
11DQ09-ND
Int. Rect. 11DQ09(Thru-Hole)
17
1
D4
LED
(Thru-Hole)
18
1
D5
1N4736A
1N4736ADICT-ND
Various Manufacturers 1N4736A(Thru-hole)
19
1
D6
1N5243A
1N5243BDICT-ND
Various Manufacturers 1N5246A(Thru-Hole)
20
1
D7
1N5235B
1N5235BDICT-ND
Various Manufacturers 1N5231A(Thru-hole)
21
2
D8,D9
MUR120
Mouser 620-MUR120
22
1
D10
1N4148
1N4148DICT-ND
AXIAL LEAD
23
1
JP2
4-pin,0.156" header
WM4702-ND
Molex 26-48-1046
24
1
JP3
3-pin,0.156" header
WM4701-ND
Molex 26-48-1036
25
2
J3,J2
PC-mount RCA jacks
901K-ND
Keystone 901
26
2
J7,J8
Screw Terminal
8190K-ND
Keystone 8190
27
1
K1
DPDT Power Relay
255-1118-ND
Aromat JW2SN-DC24V
28
1
L1
100uH
TK4300-ND
JWMiller 6000-101k or Toko 187LY-101J
29
2
L2,L3
10uH
Amidon Core
Amidon T94-2 with 38Turns, 19AWG
30
1
L6
Ferrite bead
P10190CT-ND
Panasonic EXC-3BB102H(SMT 0603)
31
1
Q1
LM7805CT
NJM78M05FA-ND
JRC NJM78M05FA-ND(TO-220)
32
3
Q2,Q3,Q4
2N7000
2N7000DICT-ND
Various Manufacturers 2N7000(TO-92)
33
1
Q5
2N3906
2N3906DICT-ND
(TO-92)
34
1
R17
0
(SMT 1206)
35
1
R55
300
P300CCT-ND
(SMT 0805)
36
1
R40
3K
P3.01KCCT-ND
(SMT 0805)
37
2
R50,R38
10K
P10.0KCCT-ND
(SMT 0805)
38
1
R47
15k
P15.0KCCT-ND
(SMT 0805)
39
1
R45
25K
P24.9KCCT-ND
(SMT 0805)
40
5
R37,R49,R52,R54,R56
50K
P49.9KCCT-ND
(SMT 0805)
41
1
R43
80K
P80.6KCCT-ND
(SMT 0805)
42
3
R39,R51,R53
100K
P100KCCT-ND
(SMT 0805)
43
1
R44
250K
P249KCCT-ND
(SMT 0805)
Browse our extensive range of Tripath and other audio parts at
www.profusionplc.com
44
45
46
47
48
49
1
1
4
2
1
7
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
2
4
2
2
1
4
2
2
1
1
1
1
4
4
2
2
2
R48
R42
R1,R3,R26,R27
R2,R9
R4
R5,R11,R12,R15,R18,
R35,R36
R16,R6
R7,R8,R21,R25
R13,R10
R14,R30
R19
R20,R22,R23,R24
R33,R34
R28, R29
SW2
U1
U2
U3
CON1,CON2,CON3,CON4
TA2022 SCREW
TA2022 washer
Screw terminal screw
35K
200K
20K
10K
2K
1K
P34.8KCCT-ND
P200KCCT-ND
Mouser 270-20K
Mouser 270-10K
Mouser 270-2K
Mouser 270-1K
(SMT 0805)
(SMT 0805)
(1/8W Thru-hole)
(1/8W Thru-hole)
(1/8W Thru-hole)
(1/8W Thru-hole)
50k Pot(no stuff)
9.1K
6;2W
232K
8.2K
1.1K
250
(no stuff)
SPDT;Mute Switch
tornado_32p_zip_6
LM358
LM339
3/8"STANDOFF
STANDOFF NUT
1/4" 4-40
NO. 4 FLAT
1/2" 4-40
3306P-503-ND
Mouser 270-9.1K
P6.2W-2BK-ND
Mouser 270-232K
Mouser 270-8.2K
Mouser 270-1.1K
Mouser 270-249
Bourns 3306P
(1/8W Thru-hole)
(2W Thru-hole)
(1/8W Thru-hole)
(1/8W Thru-hole)
(1/8W Thru-hole)
(1/8W Thru-hole)
CKN1003-ND
LM358AN-ND
LM339AN-ND
4801K-ND
H616-ND
H330-ND
H734-ND
H334-ND
Tripath Technology
National Semi LM358AN
National Semi LM339AN
Browse our extensive range of Tripath and other audio parts at
www.profusionplc.com
Browse our extensive range of Tripath and other audio parts at
www.profusionplc.com
Browse our extensive range of Tripath and other audio parts at
www.profusionplc.com
Browse our extensive range of Tripath and other audio parts at
www.profusionplc.com
Browse our extensive range of Tripath and other audio parts at
www.profusionplc.com
Browse our extensive range of Tripath and other audio parts at
www.profusionplc.com
Browse our extensive range of Tripath and other audio parts at
www.profusionplc.com