TDA8920B_2
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
Product data sheet
Rev. 02 — 07 November 2005
5 of 34
Philips Semiconductors
TDA8920B
2
×
100 W class-D power amplifier
8.
Functional description
8.1 General
The TDA8920B is a two channel audio power amplifier using class-D technology.
The audio input signal is converted into a digital pulse width modulated signal via an
analog input stage and Pulse Width Modulation (PWM) modulator. To enable the output
power transistors to be driven, this digital PWM signal is applied to a control and
handshake block and driver circuits for both the high side and low side. In this way a level
shift is performed from the low power digital PWM signal (at logic levels) to a high power
PWM signal which switches between the main supply lines.
A 2nd-order low-pass filter converts the PWM signal to an analog audio signal across the
loudspeakers.
The TDA8920B one-chip class-D amplifier contains high power D-MOS switches, drivers,
timing and handshaking between the power switches and some control logic. For
protection a temperature sensor and a maximum current detector are built-in.
The two audio channels of the TDA8920B contain two PWM modulators, two analog
feedback loops and two differential input stages. It also contains circuits common to both
channels such as the oscillator, all reference sources, the mode functionality and a digital
timing manager.
The TDA8920B contains two independent amplifier channels with high output power, high
efficiency, low distortion and a low quiescent current. The amplifier channels can be
connected in the following configurations:
•
Mono Bridge-Tied Load (BTL) amplifier
•
Stereo Single-Ended (SE) amplifiers
SGND1
11
5
signal ground for channel 1
V
SSA1
12
6
negative analog supply voltage for channel 1
PROT
13
7
decoupling capacitor for protection (OCP)
V
DDP1
14
8
positive power supply voltage for channel 1
BOOT1
15
9
bootstrap capacitor for channel 1
OUT1
16
10
PWM output from channel 1
V
SSP1
17
11
negative power supply voltage for channel 1
STABI
18
12
decoupling of internal stabilizer for logic supply
n.c.
19
-
not connected
V
SSP2
20
13
negative power supply voltage for channel 2
OUT2
21
14
PWM output from channel 2
BOOT2
22
15
bootstrap capacitor for channel 2
V
DDP2
23
16
positive power supply voltage for channel 2
V
SSD
24
17
negative digital supply voltage
Table 3:
Pin description
…continued
Symbol Pin
Description
TDA8920BTH
TDA8920BJ
