Philips CEM3000B Service Manual page 26

TENTATIVE
8. Explanation for the functions
1. Standby switch function (pin 4)
Threshold voltage of the pin 4 is set by about 2VBE.
The amplifier is turned on by the applied voltage of 2.5V or more. Also, the amplifier is turned off by the applied
voltage of 0.5V or less.
2. Muting function (pin 22)
The muted state is obtained by setting pin 22 to the ground potential, enabling audio muting.
The muting function is turned on by the applied voltage of 1V or less to the resistance of 10kΩ. And the muting
function is turn off when this pin opens.
Also, the time constant of the muting function is determined by external capacitor and resistor constants.
It is concerned with a pop noise in amplifier ON/OFF and mute ON/OFF. After enough examination, please set it.
3. ACGND pin (pin 16)
The capacitor of the pin 16 must use the same capacitance value as the input capacitor.
Also, connect to the same PREGND as the input capacitor.
Note : Information in this document is subject to change without notice.
Fig1 Standby equivalent circuit
Fig2 Mute equivalent circuit
4