TDA8920B NXP Semiconductors, TDA8920B Datasheet - Page 5

• Manufacturer Part Number: TDA8920B
• Description: The TDA8920B is a high efficiency class-D audio power amplifier with very lowdissipation
• Manufacturer: NXP Semiconductors

Philips Semiconductors
8. Functional description
TDA8920B_2
Product data sheet
8.1 General
Table 3:
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:
Symbol Pin
SGND1
V
PROT
V
BOOT1
OUT1
V
STABI
n.c.
V
OUT2
BOOT2
V
V
•
•
SSA1
DDP1
SSP1
SSP2
DDP2
SSD
Mono Bridge-Tied Load (BTL) amplifier
Stereo Single-Ended (SE) amplifiers
TDA8920BTH TDA8920BJ
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Pin description
Rev. 02 — 07 November 2005
5
6
7
8
9
10
11
12
-
13
14
15
16
17
…continued
signal ground for channel 1
negative analog supply voltage for channel 1
positive power supply voltage for channel 1
bootstrap capacitor for channel 1
PWM output from channel 1
negative power supply voltage for channel 1
not connected
negative power supply voltage for channel 2
PWM output from channel 2
bootstrap capacitor for channel 2
positive power supply voltage for channel 2
negative digital supply voltage
Description
decoupling capacitor for protection (OCP)
decoupling of internal stabilizer for logic supply
2
100 W class-D power amplifier
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
TDA8920B
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