Tripath Technology, Inc. - Technical Information
1 EB-TA2022 – Rev. 1.0/03.02
EB-TA2022
CLASS-T DIGITAL AUDIO AMPLIFIER 2 CHANNEL TA2022
EVALUATION BOARD
Technical Information
Revision 1.0 – March 2002
GENERAL DESCRIPTION
The EB-TA2022 Version 4.0 is a stereo 100W per channel audio amplifier
designed to provide a simple and straightforward environment for the evaluation
of the TA2022 amplifier. This evaluation board includes a circuit that will
automatically trim any DC offset at the output and a relay. For additional
documentation on the TA2022, see the TA2022 Data Sheet.
APPLICATIONS
Mini/Micro Component Systems
Home Theater Receivers
Car stereo head units & trunk amplifiers
Powered DVD Systems
BENEFITS
More power per cubic inch for 100W per
channel design
Simplifies thermal management
Signal Quality comparable to linear
amplifiers
Simple building block for multi-channel
design
FEATURES
High Power: 100W @ 4Ω, 1.0% THD+N
Low Noise Floor: 150uV A-weighted
Low Distortion: .02% THD+N @ 75W, 4Ω
High Efficiency: 92% for 8Ω loads
87% for 4Ω loads
Dynamic Range = 102dB
Over-Current Protection
Over and Under Voltage Protection
Over Temperature Protection
Single Ended Outputs
Tripath Technology, Inc. - Technical Information
2 EB-TA2022 – Rev. 1.0/03.02
OPERATING INSTRUCTIONS
BOARD CONNECTION DIAGRAM
Audio Source
OUT2
AGND
OUT1
+
-
TA2022
V+ Pgnd V- Vo2 GND2 GND1 Vo1
AGND 5V IN1 AGND IN2
5V
++
--
J2
J3
Speaker Right Speaker Left
AWAKE MUTE
J1
+
+--
VNN
VPP Pgnd
Three external power supplies are required to operate the EB-TA2022: VPP, VNN (referenced to
Pgnd), and 5V (referenced to Agnd). The VPP and VNN form a split rail supply referenced to Pgnd.
The 5V ground (Agnd) must be kept separate from the VPP and VNN ground (Pgnd). Agnd and Pgnd
are joined at a common point on the EB-TA2022 near headers J2 and J3.
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 4Ω
loads, single ended, as the internal current limit circuit may activate, causing the amplifier to mute.
The VPP and VNN power supply connection, J3, is through a 7-Pin 0.156” spaced header. The
female terminal housing for this header is Molex 09-50-8071. Please see TABLE 2 for header
connections.
The 5V power supply connection, J2, is through a 5-Pin 0.100” spaced header. The female terminal
housing for this header is Molex 22-01-2057. Please see TABLE 1 for header connections.
Tripath Technology, Inc. - Technical Information
3 EB-TA2022 – Rev. 1.0/03.02
TABLE 1 TABLE 2
OUTPUT
The output connection for each channel of the EB-TA2022 is made at pins 1 – 4 of header J3. The
output of the TA2022 is single-ended, therefore each output has a positive output (Vo1 and Vo2) and
a ground (GND1 and GND2).
INPUT
The input connection for each channel of the EB-TA2022 is made at pins 3 – 5 of header J2. The left
and right inputs should be connected to IN1 (pin3) and IN2 (pin5). These inputs share a common
ground referenced to Agnd (pin4).
JUMPER SETTINGS
There is a 3-pin header for the MUTE control of the TA2022. With the jumper placed in the AWAKE
position the part is un-muted by grounding (AGND) the mute pin. When the jumper is placed in the
MUTE position the mute pin is pulled high (5V) and the amplifier is muted.
OUTPUT OFFSET NULL AND RELAY
There is an automatic offset trim circuit for each channel using an LM358 op-amp. Once the LM358
trims any DC to 0Vdc a comparator allows a relay to close.
GAIN SETTING
The gain of the EB_TA2022 Version 4.0 is set to 18V/V. The gain of the TA2022 is the product of the
input stage and the modulator stage. The input stage gain is set to unity. Before changing the gain of
the TA2022, please refer to the TA2022 Amplifier Gain section of the TA2022 Data Sheet.
J3 Connector Pin# Connection
Pin1 Vo1
Pin2 GND1
Pin3 GND2
Pin4 Vo2
Pin5 VNN
Pin6 Pgnd
Pin7 VPP
J2 Connector Pin# Connection
Pin1 Agnd
Pin2 5V
Pin3 IN1
Pin4 Agnd
Pin5 IN2
Tripath Technology, Inc. - Technical Information
4 EB-TA2022 – Rev. 1.0/03.02
Performing Measurements on the EB-TA2022 Version 4.0
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 by including out of band (audio) energy.
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 has a simple two-pole output filter with excellent
performance in listening tests.
(See Application Note 4 for additional information on bench testing)
Contact Information
TRIPATH TECHNOLOGY, INC
2560 Orchard Parkway, San Jose, CA 95131
408.750.3000 - P
408.750.3001 - F
For more Sales Information, please visit us @ www.tripath.com/cont_s.htm
For more Technical Information, please visit us @ www.tripath.com/data.htm
EB-TA2022 Revised: 3/18/2001 JR.
Revision: Ver4.0
Bill Of Materials
Item Quantity Reference Part Digikey Part # Manufacturers Part# (Package)
________________________________________________________________________________________________________________
1 10 C33,C41,C42,C43,C48, 0.1uF;50V PCC1864CT-ND Panasonic ECJ-2VF1H104Z (SMT 0805)
C49,C3,C8,C9,C10
2 2 C44,C45 0.1uF;100V AVX-12061C104KAT2A (SMT 1206)
3 1 C47 390pF;50V PCC391CGCT-ND PANASONIC ECJ-2VC1H391J(SMT 0805)
4 1 C46 330pF;50V PCC331CGCT-ND PANASONIC ECJ-2VC1H331J(SMT 0805)
5 2 C35,C36,C4,C6 3.3uF;25V P6626-ND Panasonic ECE-A25Z3R3(Thru-Hole)
6 4 C37,C38,C39,C40 0.22uF;50V P4667-ND Panasonic ECQ-V1H224JL(Thru-Hole)
7 2 C29,C32 220uF;50V P10326-ND Panasonic EEU-FC1H221S(Thru-Hole)
8 1 C34 100uF;35V P5165-ND Panasonic ECA-1VM101(Thru-Hole)
9 2 C27,C28 47uF;16V P810-ND Panasonic ECE-A1CKA470(Thru-Hole)
10 1 C5 22uF, 10V P960-ND Panasonic ECE-A1AKS220(Thru-Hole)
11 3 D1,D8,D9 B1100/B B1100DICT-ND Diodes Inccorporated (SMA)
12 4 D5,D11,D12,D13 MURS120T3 MURS120T3 (SMT SMB)
13 1 D4 1N5243 1N5243BDICT-ND 13V, 500mW, DO-35
14 1 D2 1N5235 1N5235BDICT-ND 6.8V, 500mW, DO-35
15 1 D3 1N4148 1N4148DICT-ND DO-35
16 1 D6 LED
17 1 J3 7-pin,0.156" header WM4605-ND Molex 26-48-1075
18 1 J2 5-pin,0.100" header WM4203-ND Molex 22-23-2051
19 1 J1 3-pin,0.100" header WM4001-ND Molex 22-03-2031
20 2 J9,J10 Screw Terminal 8190K-ND Keystone 8190
21 1 L4 100uH TK4300-ND JWMiller 6000-101k or Toko 187LY-101J
22 2 L5,L6 11uH PA0291(Pulse Engineering)*see note 1
23 2 R47,R48 249W (SMT 0805)
24 1 R16 300W (SMT 0805)
25 5 R30,R33,R34,R35,R50 1KW (SMT 0805)
26 4 R36,R38,R39,R40 1.2KW (SMT 0805)
27 2 R1,R17 3KW (SMT 0805)
28 1 R42 8.2KW,1% (SMT 0805)
29 4 R31,R37,R41,R52 9.1KW,1% (SMT 0805)
30 2 R18,R19 10KW (SMT 0805)
31 1 R8 15KW (SMT 0805)
32 4 R32,R43,R44,R51 20KW, 1% (SMT 0805)
33 1 R7 25KW (SMT 0805)
34 1 R9 35KW (SMT 0805)
35 5 R2,R10,R12,R14,R15 50KW (SMT 0805)
36 1 R5 80KW (SMT 0805)
37 3 R3,R11,R13 100KW (SMT 0805)
38 1 R4 200KW (SMT 0805)
39 3 R45,R46,R6 249KW,1% (SMT 0805)
40 2 R56,57 6W;2W P6.2W-2BK-ND (2W Thru-hole)
41 1 U2 TA2022 Tripath Technology
42 1 U1 LM358 LM358N-ND 8-Dip
43 1 U3 LM339 LM339N-ND 14-Dip
44 3 Q1,Q2,Q4 2N7000 2N7000FS-ND TO-92
45 1 Q3 2N3906 2N3906-ND TO-92
46 1 K1 DPDT RELAY 8A,24V PB297-ND RTE24024F
47 4 CON1,CON2,CON3,CON4 3/8"STANDOFF 4801K-ND
48 4 STANDOFF NUT HEX 4-40 H616-ND
49 2 screw terminal(horiz.) J9,J10 8190k-nd Keystone 8190
50 2 screw terminal screw 1/4" 4-40 H342-ND
51 2 TA2022 washer NO. 4 FLAT H734-ND
52 2 TA2022 screw 3/8" 4-40 H781-ND
Note 1: Inductor selection is critical for optimal operation of the TA2022 as well as being an important
component in over current protection and EMI containment. Tripath recommends the customer use a
toroidal inductor for all applications with the TA2022. For typical applications we recommend
the Micrometals T68-2 core or the American Cores (Amidon) T690-06. This core has a high peak
current capability due to its low-m Carbonyl-E metal powder. A distributed air gap increases its'
energy storage capability, Which allows for a small footprint and high current capability.
The T68-2 and T690-06 cores have a 17.5mm outer diameter. Forty-four turns of 22AWG wire makes
a complete single layer winding around the toroid with six to eight layers overlapping yielding
an ideal value of 11uH. This widing pattern, which covers the core completely, aids in
shielding the electric field. It should be noted that when multiple layers are used there may be
an increase in winding capacitance, which can cause ringing and increased radiated emmisions.
Winding techniques, such as bank winding, can minimize this effect. It is important that the
innitial windings not be crossed over by the last few windings. If a few windings more than
the single layer are required it is best to wind the core with a full single layer, back off a
number of turns,and rewind over the last few windings. A larger diameter Carbonyl-E core
may be used if a single layer wound core is required. If a smaller core is required, a 15.2mm outer
diameter Carbonyl-E core may be substituted, though thermal requirements must be considered. Please
contact Tripath Applications if there are questions pertaining to this subject.
Substitution Notes:
1- ITEM#2- This component must be .1uF, 100V with X7R material characteristic and placed close
to pins 4,8 and 9,10 of TA2022 with less than 1/8" lead length to the part.
2- ITEM#7- This component should be a high frequency,low ESR capacitor. We recommend .1W,
or less and a ripple current rating of at least 1A.
3- ITEM#22- This component should be a 10A inductor with very high linearity. Please see Data Sheet
for substitution details.
4- ITEM#12- This component should be an ultra-fast PN junction rectifier diode with a maximum
Vf of 1V at 10A.
5- ITEM#11- The Bootstrap Diodes(D8,D9)should be Schottky diodes rated at least 200mA,100V,50nS.
The VN10 Diode (D1) should be a Fast Recovery, switching, or Shottky diode rated
at least 200mA,30V,50nS.
5
5
4
4
3
3
2
2
1
1
D D
C C
B B
A A
T68-2
Core(22AWG)
TA2022-100
T68-2
Core(22AWG)
Schematic 1 4.0
EB-TA2022 Ver. 4.0
B
11Friday, March 01, 2002
Title
Size Document Number Rev
Date: Sheet of
VN10FDBK
Vnsense1
Vpsense1
Vnsense1
VN10FDBK
Vpsense1
R51
20K
U2tornado_32p_zip_6
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
VBOOT2
VN10
PGND
VPP2
VN10SW
HO2COM
OUT2
VNN2
VNN1
OUT1
HO1COM
VPP1
VBOOT1
VN10FBK
AGND
V5
REF
VNSENSE
VPSENSE
AGND
V5
OAOUT1
INV1
MUTE
OAOUT2
INV2
BIASCAP
FBKGND2
FBKOUT2
FBKGND1
FBKOUT1
HMUTE
R31
9.1k
C38
0.22uF;50V
C36
3.3uF, 25V
C34
100uF;35v
C28
47uF;16v
C35
3.3uF, 25V
J10
SCREW TERMINAL
1
2
3
4
R56
6;2W
D1
B1100/B
2 1
R50
1k
C39
0.22uF;50V
L4
100uH;JWMiller 6000-101k or Toko 187LY-101J
R52
9.1k
R41
9.1k
C47
390pF;50V
D5
MURS120
21
C49
0.1uF;16v
R57
6;2W
J9
1
2
3
4
R43
20k
C43
0.1uF;50v
D8
B1100/B
21
L6
11uH
J1
HEADER 3
1
2
3
R39
1.2k
R44
20k
STA1
STANDOFF
1STA2
STANDOFF
1
R46
249k
STA4
STANDOFF
1
STA3
STANDOFF
1
C42
.1uF;16V
R45
249k
J3
CON7
1
2
3
4
5
6
7
J2
CON5
1
2
3
4
5
C37
0.22uF;50V
C33
0.1uF;25v
R34
1k
R42
8.2k
D11
MURS120
2 1
R47
250
C41
.1uF;16V
C32
220uF;50V
R30
1k
C46
330pF;50V
D13
MURS120
2 1
R48
250
R36
1.2k
C40
0.22uF;50V
C29 220uF;50V
L5
11uH
C27
47uF;16v
C44
0.1uF;100V
D9
B1100/B
2 1
C45
0.1uF;100V
R33
1k
R40
1.2k
R32
20K
R38
1.2k
C48
0.1uF;16v
R37
9.1k
D12
MURS120
21
R35
1k
R1
3k D6 LED
IN2
V-
IN2
5V
IN1
5V
Vo2b
V+
5V
Vo1b
5V
V-
MUTE
V-
V-
V+
AGnd
MUTE
IN1
V+
VN10
AGnd
AGnd
AGnd
PGnd
PGnd
PGnd
PGnd
PGnd
PGnd
HMUTE
FBKGND1
FBKGND2
Vo2a
Vo1a
AGnd
5
5
4
4
3
3
2
2
1
1
D D
C C
B B
A A
SCHEMATIC 2
4.0
OFFSET CORRECTION & RELAY CIRCUIT
B
22Friday, March 01, 2002
Title
Size Document Number Rev
Date: Sheet of
C6
3.3uF
Q1
2N7000
2
31
D2
1N5235 21
C9
0.1uF
R19
10k
D4
1N5243
21
R17
3k
C5
22uF, 10V
R15
50K
Q4
2N7000
2
31
R3
100K
R2
50k
D3
1n4148
2 1
C10
0.1uF
R8
15k
+
-
U1A
LM358
3
21
8 4
Q3
2N3906
3
2
1
C4
3.3uF
R7
25k
R4
200k
R5
80k
+
-
U3A
LM339
7
61
312
R6
250k
R13
100k
R9
35k
R12
50k
K1
DPDT RELAY
64
8
53
7
2
1
R11
100K
R10
50k
R16
300
C8
0.1uF
+
-
U3B
LM339
5
42
312
+
-
U1B
LM358
5
67
8 4
R14
50k
R18
10k
Q2
2N7000
2
31
+
-
U3D
LM339
11
10 13
312
C7
0.1uF
+
-
U3C
LM339
9
814
312
Vo2a
FBKGND2
VCOMP
Vo1b
PGND
PGND
VCOMP
VCOMP
PGND
Vo2a
Vo1a
PGND
VCOMP
Vo1a
HMUTE
VCOMP
FBKGND1
PGND
VCOMP
V+
Vo2b
VCOMP
PGND
PGND
V+
PGND
PGND
PGND
PGND
