Tait TM8100 mobiles Service Manual page 84

Auxiliary Audio
Output
84 Circuit Descriptions
The source for the auxiliary audio output signal
by IC204 ( ball). The DAC output of IC204 is low-pass filtered to
RAMPDAC
remove high-frequency artefacts. The low-pass filter, formed by IC201
(pins 1 to 3), R219, R220, R221, R224, C206, C208 and C210, is a third-
order Butterworth type with a cut frequency of approximately 12kHz.
The output of the low-pass filter is amplified by 6dB by a buffer amplifier,
IC201 (pins 5 to 7), and fed via R207 and R208 to drive the
interface line. The DC bias for this signal path is provided by IC204 and
OUT
is approximately 1.2V when operational. The offset at
approximately 2.4V owing to the gain of the buffer amplifier.
is provided
CDC AUD TAP OUT
CDC AUD TAP
CDC AUD TAP OUT
TM8100/TM8200 Service Manual
© Tait Electronics Limited November 2007
is