T r i p a t h T e c h n o l o g y , I n c . - T e c h n i c a l I n f o r m a t i o n
1
TA2021B 4.0/07.03
TA2021B
STEREO 25W (4
) CLASS-TTM DIGITAL AUDIO AMPLIFIER DRIVER
USING DIGITAL POWER PROCESSING (DPPTM) TECHNOLOGY
T e c h n i c a l I n f o r m a t i o n
R e v i s i o n 4 . 0 J u l y 2 0 0 3
General Description
The TA2021B is a 25W (4
) continuous average per channel Class-T Digital Audio Power Amplifier IC
using Tripath's proprietary Digital Power Processing (DPP
TM
) technology. Class-T amplifiers offer both
the audio fidelity of Class-AB and the power efficiency of Class-D amplifiers.
Applications
DVD Receivers
Mini/Micro Component Systems
Computer / PC Multimedia
Cable Set-Top Products
Televisions
Battery Powered Systems
Benefits
Fully integrated solution with internal FETs
Easier to design-in than Class-D
Dramatically improves efficiency versus Class-AB
amplifiers
Signal fidelity equal to high quality linear
amplifiers
High dynamic range compatible with digital media
such as CD and DVD, and internet audio
Typical Performance
THD+N vs Output Power
0.01
10
0.02
0.05
0.1
0.2
0.5
1
2
5
TH
D+
N (
%
)
600m
20
1
2
3
4 5 6 7 8 9
Output Power (W)
VDD=14.2V
Av=12V/V
BW=22-22kHz
Features
Class-T architecture
Single Supply Operation
"Audiophile" Quality Sound
0.05% THD+N @ 13W 4
0.1% THD+N @15.5W 4
0.1% IHF-IM @ 1W 4
High Power
25W @ 4
, 10% THD+N, V
DD
=14.6V
23.5W @ 4
, 10% THD+N, V
DD
=14.2V
14W @ 8
, 10% THD+N, V
DD
=14.2V
High Efficiency
88% @ 13.5W 8
81% @ 25W 4
Dynamic Range = 100 dB
Mute and Sleep inputs
Turn-on & turn-off pop suppression
Over-current protection
Over-temperature protection
Bridged outputs
36-pin PSOP "Slug-Up" package
RL=8
RL=4
T r i p a t h T e c h n o l o g y, I n c . - T e c h n i c a l I n f o r m a t i o n
2
TA2021B 3.0/04.03
Absolute maximum ratings
(Note 1)
SYMBOL PARAMETER
Value
UNITS
V
DD
Supply Voltage
16
V
V5
Input Section Supply Voltage
6.0
V
SLEEP
SLEEP Input Voltage
-0.3 to 6.0
V
MUTE
MUTE Input Voltage
-0.3 to V5+0.3
V
T
STORE
Storage Temperature Range
-40
to 150
C
T
A
Operating Free-air Temperature Range
-40 to 85
C
T
J
Junction Temperature
150
C
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. See the
table below for Operating Conditions.
Note 2: Human body model, 100pF discharged through a 1.5K
resistor.
Note 3: Machine model, 220pF discharged through all pins.
Operating Conditions
(Note 4)
SYMBOL PARAMETER MIN.
TYP.
MAX.
UNITS
V
DD
Supply Voltage
8.5
14.2
14.6
V
V
IH
High-level Input Voltage (MUTE, SLEEP)
3.5
V
V
IL
Low-level Input Voltage (MUTE, SLEEP)
1
V
Note 4: Recommended Operating Conditions indicate conditions for which the device is functional. See
Electrical Characteristics for guaranteed specific performance limits.
Thermal Characteristics
SYMBOL PARAMETER
VALUE UNITS
JC
Junction-to-case Thermal Resistance
2.5
C/W
JA
Junction-to-ambient Thermal Resistance (still air)
50
C/W
T r i p a t h T e c h n o l o g y, I n c . - T e c h n i c a l I n f o r m a t i o n
3
TA2021B 3.0/04.03
Electrical Characteristics
(Notes 6, 7)
See Test/Application Circuit. Unless otherwise specified, V
DD
= 14.2V, f = 1kHz, Measurement
Bandwidth = 22kHz, R
L
= 4
, T
A
= 25
C.
SYMBOL PARAMETER
CONDITIONS MIN.
TYP.
MAX.
UNITS
P
O
Output Power
(Continuous Average/Channel)
THD+N = 0.1%
R
L
= 4
R
L
= 8
THD+N = 10%
R
L
= 4
R
L
= 8
15.5
9
23.5
14
W
W
W
W
P
O
Output Power (V
DD
=14.6V)
(Continuous Average/Channel)
THD+N = 0.1%
R
L
= 4
R
L
= 8
THD+N = 10%
R
L
= 4
R
L
= 8
16.5
9.5
25
14.8
W
W
W
W
I
DD,MUTE
Mute Supply Current
MUTE = V
IH
5.5
7
mA
I
DD, SLEEP
Sleep Supply Current
SLEEP = V
IH
0.25
2
mA
I
q
Quiescent Current
V
IN
= 0 V
64
75
mA
THD + N Total Harmonic Distortion Plus
Noise
P
O
= 10W/Channel
0.035
%
IHF-IM
IHF Intermodulation Distortion
19kHz, 20kHz, 1:1 (IHF)
0.1
0.3
%
SNR Signal-to-Noise
Ratio
A-Weighted, P
OUT
= 25W, R
L
= 4
100
dB
CS Channel
Separation
0dBr = 1W, R
L
= 4
, f = 1 kHz
74 80 dB
PSRR
Power Supply Rejection Ratio
Vripple = 100mV
60
80
dB
Power Efficiency
P
OUT
= 13.5W/Channel, R
L
= 8
88 %
V
OFFSET
Output Offset Voltage
No Load, MUTE = Logic low
50
150
mV
V
OH
High-level
output
voltage
(FAULT & OVERLOADB)
3.5
V
V
OL
Low-level
output
voltage
(FAULT & OVERLOADB)
1
V
e
OUT
Output Noise Voltage
A-Weighted, input AC grounded
100
V
Note 6:
Minimum and maximum limits are guaranteed but may not be 100% tested.
Note 7:
For operation in ambient temperatures greater than 25
C, the device must be de-rated based on the
maximum junction temperature and the thermal resistance determined by the mounting technique.
T r i p a t h T e c h n o l o g y, I n c . - T e c h n i c a l I n f o r m a t i o n
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TA2021B 3.0/04.03
Pin Description
Pin
Function
Description
2, 3
DCAP2, DCAP1
Charge pump switching pins. DCAP1 (pin 3) is a free running 300kHz square
wave between VDDA and DGND (12Vpp nominal). DCAP2 (pin 2) is level shifted
10 volts above DCAP1 (pin 3) with the same amplitude (12Vpp nominal),
frequency, and phase as DCAP1.
4, 9
V5D, V5A
Digital 5VDC, Analog 5VDC
5, 8,
17
AGND1, AGND2,
AGND3
Analog Ground
6
REF
Internal reference voltage; approximately 1.0 VDC.
7
OVERLOADB
A logic low output indicates the input signal has overloaded the amplifier.
10, 14
OAOUT1, OAOUT2
Input stage output pins.
11, 15
INV1, INV2
Single-ended inputs. Inputs are a "virtual" ground of an inverting op-amp with
approximately 2.4VDC bias.
12
MUTE
When set to logic high, both amplifiers are muted and in idle mode. When low
(grounded), both amplifiers are fully operational. If left floating, the device stays in
the mute mode. This pin should be tied to GND if not used.
16
BIASCAP
Input stage bias voltage (approximately 2.4VDC).
18
SLEEP
When set to logic high, device goes into low power mode. If not used, this pin
should be grounded
19
FAULT
A logic high output indicates thermal overload, or an output is shorted to ground,
or another output.
20, 35
PGND2, PGND1
Power Grounds (high current)
22 DGND
Digital
Ground
24, 27;
31, 28
OUTP2 & OUTM2;
OUTP1 & OUTM1
Bridged outputs
25, 26,
29, 30
VDD2, VDD2
VDD1, VDD1
Supply pins for high current H-bridges.
13, 21,
23, 32,
34
NC
Not connected. Not bonded internally.
33
VDDA
Supply pin for analog section.
36
CPUMP
Charge pump output (nominally 10V above VDDA)
1
5VGEN
Regulated 5VDC source used to supply power to the input section (pins 4 and 9).
TA2021B Pinout
FAULT
PGND2
NC
NC
VDD2
OUTM2
OUTM1
VDD1
NC
VDDA
NC
PGND1
CPUMP
DCAP2
AGND3
BIASCAP
INV2
OAOUT2
MUTE
INV1
OAOUT1
V5A
AGND2
OVERLOADB
REF
AGND1
V5D
DCAP1
36-pin Slug-Up SOP Package
(Top View)
+5VGEN
OUTP1
VDD1
VDD2
OUTP2
DGND
NC
SLEEP
30
19
20
21
22
23
24
25
26
27
28
29
36
31
32
33
34
35
1
15
14
13
11
10
12
9
8
7
6
5
4
3
2
16
17
18
T r i p a t h T e c h n o l o g y, I n c . - T e c h n i c a l I n f o r m a t i o n
5
TA2021B 3.0/04.03
Application / Test Circuit
TA2021B
R
L
4
or *8
MUTE
FAULT
OVERLOADB
(14.2V)
C
I
2.2uF
OAOUT1
OAOUT2
INV1
INV2
OUTP1
OUTM1
OUTP2
OUTM2
VDDA
+5VGEN
BIASCAP
DCAP2
DCAP1
C
I
2.2uF
C
A
0.1uF
C
D
0.1uF
CPUMP
10
11
20
1
33
29
26
7
19
31
28
24
27
36
2
3
15
14
12
16
R
F
20K
18
R
Z
10
, 1/2W
R
Z
10
, 1/2W
C
Z
0.47uF
C
P
1uF
+
+
5V
SLEEP
5V
5V
+12V
0.1uF
REF
R
REF
8.25K
, 1%
6
1M
All Diodes Motorola MBRS130T3
* Use C
o
= 0.22
F and C
z
= 0.22
F for 8 Ohm loads
VDD1
PGND1
VDD1
PGND1
VDD2
VDD2
PGND2
PGND2
Note: Analog and Digital/Power Grounds must
be connected locally at the TA2021
C
S
0.1uF
C
S
0.1uF
To Pin 1
4
5
V5D
8
AGND1
AGND2
V5A
22
C
S
0.1uF
DGND
VDD1
PGND2
35
PGND1
180uF, 16V
VDD2
VDD
+
+
+
Processing
&
Modulation
Processing
&
Modulation
*C
o
0.47uF
L
o
10uH, 2A
9
(Pin 8)
Analog Ground
Digital/Power Ground
(Pin 35)
(Pin 35)
(Pin 20)
(Pin 20)
To Pins 4,9
R
I
20K
(Pin 8)
R
F
20K
R
I
20K
AGND3
17
180uF, 16V
C
SW
C
SW
*C
o
0.47uF
L
o
10uH, 2A
R
L
4
or *8
L
o
10uH, 2A
L
o
10uH, 2A
*C
o
0.47uF
*C
o
0.47uF
C
Z
0.47uF
C
SW
0.1uF
C
SW
0.1uF
C
S
0.1uF
D
H
D
O
D
O
D
O
C
DO
0.1uF
C
DO
0.1uF
(Pin 35)
(Pin 20)
13
NC
21
23
25
30
32
34
VDD1
VDD2
VDD1 (pin 29,30)
VDD1 (pin 29,30)
VDD2 (pin 25,26)
VDD2 (pin 25,26)
D
H
D
H
D
H
D
O
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