Technical description and composition of the PHILIPS 32PFL7404H TV, type of panel and applicable modules. The composition of the modules.PHILIPS
Model: 32PFL7404H / 60
Chassis / Version: Q548.1E LA
Panel: LC320WUF-SBN1 code 181
T-CON: 6870C-4000H LC320
Inverter (backlight): PLHL-T826A
PWM Inverter: OZ9966GN
Power Supply (PSU): PLHL-T826 A 2300KPG102B-F
PWM Power: L6599D (PWM Resonant), FAN7530 (PFC)
MOSFET Power: 2SK3561, FDD5N50
MainBoard: 313912364422 313926866322 PNL 3139 123 64422 BD 3139 123 64432 WK906.5
IC MainBoard: PNX85439EH24180, NAND016W3828N, TDA9596HL / C1
Tuner: HD1816AF 2422 542 00063
Control: Remote: 2422 549 02344, IR: 2722 171 00726 (090630-07192)
Specifications 32PFL7404H
PHILIPS 32PFL7404H
General recommendations for repairing TV LCD
Repair of all electronic devices, including the PHILIPS 32PFL7404H / 60 TB1C TV, it is advisable to start with an external examination of its external and internal elements. You should also pay attention to the condition of the case elements, connectors, cords, loops and buttons. Often, for certain external signs, it is possible to draw certain conclusions about the reasons for the failure of certain elements of the circuit even before the necessary measurements are made, which will determine the further algorithm for troubleshooting and localizing the defect. In some cases, faulty elements can be seen with the naked eye, for example, charred resistors or swollen metal-ceramic capacitors, or electrolytic in rectifier filters. Ring cracks formed in the soldered terminals of transformers or heating elements of the circuit are also frequent sources of many malfunctions with a variety of external manifestations.
Power Module Repair
If the 32PFL7404H / 60 TB1C TV does not turn on, does not emit any sounds when it is turned on, and also no indicators on the front panel light or blink - there is a high probability of a malfunction in the power module. In some cases, only the regulator or power converter of the control processor may be faulty, which is typical for some PHILIPS models. When diagnosing and repairing the power supply, first of all, replace the swollen capacitors of the filter of the secondary rectifiers and check the fuse and, if it is broken, it is necessary to identify the cause. Often in such cases, an avalanche (thermal) breakdown is detected in the power semiconductor elements of the module - rectifier diodes or power key.
It should be remembered that the N-FET keys used in flyback converters rarely fail without their own sake without any reasons that must be sought by checking other elements of the circuit. Often the breakdown is caused by malfunctions of electrolytic capacitors or semiconductor elements in the primary circuit, or by a break in the resistors in the stabilization circuits. The L6599D FAN7530 PWM controller chip can also cause a breakdown of the power switch of the converter.
It is somewhat more difficult to find faults in the converter of the power module with an active KKM (power factor corrector).
Inverter Repair
If the PHILIPS 32PFL7404H / 60 TB1C does not have an image, there is sound and the channels are switched, there is a possibility of a malfunction of the backlight lamps or their power converter - inverter. Sometimes when you turn on the image appears and disappears immediately. In such cases, it is necessary to check the electrolytic capacitors of the power filter of the inverter itself, including in the secondary rectifier of the main PSU.
The operation of the power circuits of the inverter and the backlight in the normal mode are controlled by special protection, which is organized for fire safety, for example, to disconnect during short circuits or breaks in high voltage connections or when the lamps are depressurized. This protection makes it difficult to diagnose and repair the inverter.
In these cases, special care must be taken in view of the risk of failure of the power elements. After completing all repair work, it is imperative to restore the protection circuits for full and safe further operation of the TV by the user.
Repair Main Board
In cases of attempts to repair the motherboard, it is necessary to check the operability of linear stabilizers or power converters of its microcircuits and, if possible, update the software (software).
Once again, we remind TV users: you should not make attempts to repair it yourself without the appropriate knowledge, experience and the necessary qualifications! Trust the repair only to professionals with sufficient experience in the field of electronic equipment repair.
Service manual and schematic diagram 32PFL7404H/60 TB1C Chassis Q548.1E LA
The appearance of MainBoard 313912364422 is shown in the figure below:313912364422
PSU Advanced
The 32PFL7404H / 60 TV is equipped with a PLHL-T826 power supply module using the PFC (Power Factor Correction) scheme acting as an active filter to eliminate the higher harmonic components of the current consumption. The boost converter based on the FAN7530 PWM controller does not allow the electrolytic capacitor of the input rectifier filter to be connected directly to the network directly through open diodes, when the value of the charge current determines its reactance (about 15-30 ohms at a frequency of 50 Hz). As a result of the conversion, the charging current of the capacitor will be determined in such a way that the envelope of the high-frequency pulses of the input current will repeat the phase and shape of the sine wave of the input voltage. The health check of the PFC unit is carried out by measuring the DC voltage on the capacitor of the rectifier network. In operating mode, it should be around 380V, in standby approximately 300V.
The appearance of the power supply
Main features of the PHILIPS 32PFL7404H device:
Installed matrix (LCD panel) LC320WUF-SBN1 code 181.
The matrix control uses the Timing Controller (T-CON) 6870C-4000H.
To power the backlight, the PLHL-T826A inverter is used, it is controlled by the OZ9966GN PWM controller.
The necessary supply voltages for all nodes of the PHILIPS 32PFL7404H TV are generated by the PLHL-T826 power supply module or its analogs using L6599D (PWM Resonant), FAN7530 (PFC) microchips and 2SK3561, FDD5N50 type power switches.
MainBoard - the main board (motherboard) is a module 313912364422, using chips PNX85439EH24180, NAND016W3828N, TDA9596HL / C1 and others.
The tuner HD1816AF 2422 542 00063 provides the reception of television programs and tuning to channels.
Additional technical information about the panel:
Brand: LG Display
Model: LC320WUF-SBN1
Type: a-Si TFT-LCD, Panel
Diagonal size: 31.5 inch
Resolution: 1920x1080, FHD
Display Mode: S-IPS, Normally Black, Transmissive
Active Area: 698.4x392.85 mm
Surface: Antiglare (Haze 10%), Hard coating (3H)
Brightness: 500 cd / m²
Contrast Ratio: 1300: 1
Display Colors: 1.06B (8-bit + FRC)
Response Time: 6 (G to G)); 8 (MPRT)
Frequency: 120Hz
Lamp Type: 16 pcs EEFL Without Driver
Signal Interface: LVDS (4 ch, 10-bit), 92 pins
Voltage: 12.0V