Skip to main content

Philips QFU2 1E Chassis LCD TV SMPS circuits troubleshooting


Power Supply Unit
For 32", 37", and 55" sets, power supply units should be repaired on component level.  All other power supplies are a black box for Service. When any of these power supplies is defective, a new board must be ordered and the defective one must be returned, unless the main fuse of the board is broken. Always replace a defective fuse with one with the correct specifications. This part is available in the regular market.
Replace safety components, indicated by the symbol , only by components identical to the original ones. Any other component substitution (other than original type) may increase risk of fire or electrical shock hazard.
PLDC-P109B (32" sets) and PLDD-P109A (37" sets)
The output voltages to the chassis are:
* V STB (+3.3 V; stand-by mode)
* V SSB (+12.3 V; on-mode)
* V SND (+12.3 V; audio circuit).
Test instructions 32" & 37"
* check fuse (F101)
* standby check VSTB (C306), measure 3.3 V
* PFC voltage check (C644), measure 380 - 400 V; if no PFC applied, measure 311 @ 220 V
* multi-level check V SSB (C203), measure 12.3 V
* multi-level check V SND (C206), measure 12.3V
* reference voltage check (U401), measure 5.96 V (appr.).
PLDK-P107B (55" sets)
The output voltages to the chassis are:
* V STB (+3.3 V; stand-by mode)
* V SSB (+12.3 V; on-mode)
* V SND (+12.3 V; audio circuit).
Test instructions 55"
* check fuse (F101)
* standby check VSTB (C301), measure 3.3 V
* PFC voltage check (C646), measure 380 - 400 V; if no PFC applied, measure 311 @ 220 V
* multi-level check V SSB (C203), measure 12.3 V
* multi-level check V SND (C202), measure 12.3V
* reference voltage check (U401), measure 5.96 V (appr.).
A 272217190604 - 272217190605 PSL. Power Supply Unit with Integrated LED Driver Schematic
A 272217190609 PSU Circuit diagram
A 272217190611 PSU Circuit diagram


Comments

Popular posts from this blog

Altec Lansing 353A – power amplifier – vacuum tube type – Circuit diagram 6L6 12AX7

Used tubes – 12AX7 [pre-amplifier, tone control and audio pre-amplifier] – 6L6GC [audio output] Circuit diagram Tube pin-out -6L6 Tube pin-out 12AX7

Making PC USB LCD controller project

This really a work that so cool if you like modif PC. So this is a USB interface for alphanumeric LCD display like 4 × 20 which can be controlled with LCD Smartie program. USB interface is implemented by using PIC18F2550 microcontroller, Using USB LCD modules. Below is a project of the USB LCD controller. Schematic circuit and PCB design source  | link

TV REMOTE JAMMER CIRCUIT USING NE555