NXP Semiconductors TFA9810 - Manual (Page 5)

TFA9810_3 © NXP B.V. 2008. All rights reserved.
Product data sheet Rev. 03 — 20 February 2008 5 of 29
NXP Semiconductors
TFA9810
Audio amplifier 2 x 12 W
8. Functional description
8.1 General
The TFA9810 is a dual-switching power comparator. It is the main building block for a
stereo high-efficiency Class D audio power amplifier system. It contains two full-bridge
BTL power stages, drive logic, protection-control logic and full differential input
comparators and references (see
Figure 1 ). By using this power comparator a compact
closed-loop self-oscillating digital amplifier system or open-loop system can be built. A
second-order low-pass filter converts the Pulse Width Modulation (PWM) output signal
into an analog audio signal across the speaker.
8.2 Interfacing
The pins ENABLE and SO/OL control the operating mode of the TFA9810. Both the
ENABLE and the SO/OL pins refer to V
SSD(HW)
.
When the SO/OL pin is connected to V
SSA
the TFA9810 is in self-oscillating mode: when
the SO/OL pin is floating the TFA9810 is in open-loop mode.
The TEST pin needs to be connected to V
DDA
in both situations.
The device has two modes: SLEEP and OPERATING.
IN2N 14 Negative input comparator channel 2
IN2P 15 Positive input comparator channel 2
STAB2 18 Decoupling of internal 11 V regulator for channel 2 drivers
V
SSP2
19 Negative power-supply voltage channel 2
BOOT2N 20 Bootstrap high-side driver negative output channel 2
OUT2N 21 Negative output channel 2
BOOT2P 22 Bootstrap high-side driver positive output channel 2
OUT2P 23 Positive output channel 2
V
DDP2
24 Positive supply voltage power channel 2
V
DDP1
25 Positive power supply voltage channel 1
OUT1P 26 Positive output channel 1
BOOT1P 27 Bootstrap high-side driver positive output channel 1
OUT1N 28 Negative output channel 1
BOOT1N 29 Bootstrap high-side driver negative output channel 1
V
SSP1
30 Negative supply voltage power channel 1
STAB1 31 Decoupling of internal 11 V regulator for channel 1 drivers
Table 3. Pin description …continued
Symbol Pin Description
Table 4. SO/OL connections
Interfacing
SO/OL connected to Configuration
V
SSD(HW)
Self-oscillating
Open Open-loop