Read Sharp SD-EX200 (serv.man9) Service Manual online
speaker terminals + and - is set to 0
Input : AUX
Signals from CNA101 are coupled by CA100 and CA101 and
then sent into the A/D converter IC (ICA100).
Signals from the A/D converter IC (ICA100) are converted to
1-bit signals and sent differentially. Refer to the technical
manual of SM-SX100 for the details of conversion to 1-bit
1-bit signals switched by the output IC (ICA101 and ICA102)
are converted to analog signals through the lowpass filter
consisting of LA101 ~ LA107. The low pass filter functions
when a frequency exceeds 20 kHz, and reduces it by approx.
3 dB when it reaches approx. 40 kHz.
The 1-bit signals switched by the output IC (ICA101 and
ICA102) oscillate between positive and negative voltage.
After resistance-division, the signals are fed back to the A/D
converter IC (ICA100) through NF resistance 75 kohms (RA155
~ RA158). The peak-to-peak voltage reaches approx. 5 V.