VESTEL MB130 IDTV, Service Manual

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Table3.2: Recommended Operating Conditions
B. HEADPHONE AMPLIFIER (U120)
Description
The AD22657B is a 2-Vrms cap-less stereo line driver. The device is ideal for single supply electronics.
Cap-less design can eliminate output dc-blocking capacitors for better low frequency response and save cost.
The AD22657B is capable of delivering 2-Vrms output into a 10k ohm load with 3.3V supply. The gain
settings can be set by users from 1V/V to 10V/V externally. The AD22657B has under voltage protection to
prevent POP noise. Build-in shutdown control and de-pop control sequence also help AD22657B to be a pop-
less device.
The AD22657B is available in a 10-pin MSOP package.
Features

Operation Voltage: 3V to 3.6V

Cap-less Output
o
Eliminates Output Capacitors
o
Improves Low Frequency Response
o
Reduces POP/Clicks

Low Noise and THD
o
Typical SNR 107dB
o
Typical Vn 7uVrms
o
Typical THD+N < 0.02%

Maximum Output Voltage Swing into 2.5k Load
o
2Vrms at 3.3V Supply Voltage

Single-ended Input

External Gain Setting from 1V/V to 10V/V

Fast Start-up Time: 0.5ms

Integrated De-Pop Control