Sony FWD-40LX1, Руководство по обслуживанию

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3-7
FWD-40LX1
DC-DC converter
D3.3 V is output from the output voltage (13 V) of a main converter using a step-down converter
consisting of IC6500, Q6501, L6501, and C6522. Similarly, 3.3 V is output from IC6500, Q6601,
L6601, and C6602, and 5 V is output from IC6600, Q6500, L6502, and C6521. D5 V is output from
IC6600, Q6600, L6602, and C6621. A3.3 V is output to CN6402 (1-3 pins) and CN6407 (3-5 pins), and
D3.3 V is output to CN6402 (6-8 pins) and CN6407 (9-11 pins). 5 V is output to CN6409 (1-3 pins).
The DC-DC converter is turned on and off by setting the POWER_ON signal (at pin 9 of CN6404) and
PON-PANEL signal (at pin 7 of CN6404) from a microcomputer to high and low. A high-level signal is
first input from a POWER_ON signal (at pin 9 of CN6404) to IC6500 (9-10 pins) and IC6600 (10 pins),
and A5 V, A3.3 V, and D3.3 V are output. After two seconds, a high-level signal is input from the PON-
PANEL signal (at pin 7 of CN6404) from a microcomputer to IC6600 (9 pins), and a PNL_Vcc signal is
output.
Also, an input voltage of 13 V is converted into 5 V and 9 V for output using a chopper regulator
(consisting of IC6450 and IC6451).
D5 V is output to CN6408 (1 pin), CN6401 (4-5 pins), and CN6406 (5-8 pins), and 9 V is output to
CN6401 (1 pin) and CN6406 (3 pins).
Main ON/OFF control & protection circuit
An active filter and main converter are turned on and off by setting the POWER_ON signal (at pin 9 of
CN6404) from a microcomputer to high and low. When a POWER_ON signal is high, the active filter is
activated if Q600 is turned on and if RY6301 is turned on. After that, the main converter is activated.
When a POWER_ON signal is low, Q6300 is turned off and RY6301 is turned off. At that time, the
operation of both the active filter and main converter stops.