TDA8933B Datasheet, PDF (12/42 Pages) NXP Semiconductors – Class D audio amplifier

NXP Semiconductors
TDA8933B
Class D audio amplifier
8.7 Output voltage buffers
When pin POWERUP is set HIGH the half-supply output voltage buffers are switched on
in asymmetrical configuration. The start-up will then be pop-free because the device
starts switching when the capacitor on pin HVPREF and the SE capacitors are completely
charged.
Output voltage buffer pins:
• Pins HVP1 and HVP2: The time required for charging the SE capacitor depends on its
value. The half-supply voltage output is disabled when the TDA8933B is used in a
symmetrical supply application.
• Pin HVPREF: This output voltage reference buffer charges the capacitor on pin
HVPREF.
• Pin INREF: This output voltage reference buffer charges the input reference capacitor
on pin INREF, which applies the bias voltage for the inputs.
9. Internal circuitry
Table 7.
Pin
1
16
17
32
Internal circuitry
Symbol
Equivalent circuit
V_SSD(HW)
1, 16,
17, 32
V_DDA
V_SSA
001aad784
2
IN1P
3
IN1N
12
INREF
2, 15
14
IN2N
15
IN2P
V_DDA
2 kΩ
± 20 %
V/I
48 kΩ
± 20 %
12
3, 14
2 kΩ
± 20 %
48 kΩ
± 20 %
HVPREF
V/I
V_SSA
001aad785
TDA8933B_1
Preliminary data sheet
Rev. 01 — 23 October 2008
© NXP B.V. 2008. All rights reserved.
12 of 42