LG LRTBC1825T Service, Руководство по обслуживанию, Страница: 21 / 38

7-4 Explanation of ice maker circuits
7-4-1 Power circuit
The secondary party of transformer consists of power (12Vdc) for driving display and relay and power (5Vdc) supplying
power to MICOM and IC.
In this case, voltage at each part is as follows:
VA1 is parts for preventing over-voltage and noise and plays a role of protecting elements of the secondary part of trans-
former as the inside of element becomes short and is broken and power fuse is cut off when power of more than 175V is
applied.
7-4-2 Vibration circuit
Circuit used for synchronous clock generation for transmitting/receiving information of the inside logic elements of IC and
basic time generation for calculating time. Rated parts must be used as counting time is changed at the IC1 or the OSC1
does not operate if SPEC would be changed.
7-4-3 Reset circuit
The reset circuit is a circuit that initializes various parts such as RAM, etc inside of the MICOM (IC1) and starts the whole of
function from the initial status and ‘low’ voltage is applied for a constant time (10ms) at the reset terminal of the MICOM at
the start of power input.
The reset terminal is at 5V during general operation (the MICOM does not operate in the defect of the reset IC).
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Part Both ends of VA1 Both ends of CE2 Both ends of CE3
Voltage 115Vac 12Vdc 5Vdc