9-1) Power Circuit; 9-2) Oscillator - Samsung RB1855SW Service Manual

Circuit Descriptions

9-1) Power Circuit

Voltage
(DC 12V)
Vcc (DC 5V)
1) The input AC voltage of DC-trans secondary registers 8V at CN10 between ①~③. The rectified
voltage passed through D101 ~ 104 becomes DC 5V through voltage regulator MC7805(REG1).
The power(DC5V) is supplied to the power around micom and sensor detector.
2) The input AC Voltage of DC-trans secondary registers 15V at CN10 between ⑤~⑦. The rectified
voltage passed throush D105 ~ D108 becomes DC 12V through voltage regulator MC7812CT
(REG2). The power (DC12V) is supplied to the relay operation and LED display.

9-2) Oscillator

Oscillating Frequency
Port
Xin(#19)
Xout(#20)
±0.5% Error
4.00MHz
4.00MHz
Circuit used
Relay Operation & LED Display
Power around MICOM & Sensor Detector
It is designed for clock generation and time
calculation for synchronizing transmission and
reception on the logic elements inside the MICOM.
If the X-TAL specification changes, MICOM may
make an error.
(The standard components should be used.)
28