Technical description and composition of the LG 32LB572U TV, panel type and applicable modules. The composition of the modules.LG LED
Model: 32LB572U
Chassis / Version: LE46B
Panel: NC320DXN VSBP2
LED driver (backlight): integrated into PSU; 117V 250mA
PWM LED driver: SSC1S311, A27RAE
MOSFET LED driver: STD11N65M5, MDHT4N20Y
Power Supply (PSU): LGP32-14PL1 EAX65391401 (3.0)
PWM Power: NCP1251 (PWM SOT23-6), NR134S
MOSFET Power: KP8N65
MainBoard: EAX65610905 (1.0)
IC MainBoard: EEPROM: 24C256, SOUND: Audio: NTP7513, D9PXV, D9PTK, 100GEA, TPA6138
Tuner: TDJM-G101D
Specifications 32LB572U
LG 32LB572U
General repair guidelines for TV LCD LED
Possible manifestations of defects
- The LG 32LB572U TV does not turn on. There are no signs of operability. The indicators on the front panel do not light or flash, the TV does not respond to the remote control and control buttons.
A malfunction in such cases should begin to be sought in the power supply circuits of LGP32-14PL1. It is necessary to measure its secondary output voltages, and if they are absent, check the power switches (KP8N65) and rectifier diodes in the converters for a short circuit.
In case of breakdowns of semiconductors in secondary circuits, the converter can usually work abnormally in the short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse often breaks.
Breakdown of power switches (MosFet) in pulsed sources is sometimes caused by malfunctions of other circuit elements, for example, in circuits supplying a PWM controller, frequency-setting or damper ones, as well as in negative feedback circuits (OOS) of stabilization. PWM controllers (PWM) NCP1251 (PWM SOT23-6), NR134S, if they do not have visible damage to the case and open fault between the terminals, are usually checked by replacement.
- There is no image, but there is sound, it responds to the remote. Or the image appears when you turn it on and immediately disappears
In most of these cases, a malfunction is detected in the nodes and backlight elements of the LED panel. The reason can be both in the power supply of the LEDs, in their serviceability (breakdown or breakage), as well as in the violation of the contact connections of the LED strips.
When trying to detect a break in the LED lines, it should be taken into account that it is difficult to do this without disassembling the panel. For example, a current source is needed to open PN junctions connected in series.
- The indicator on the front panel blinks, the TV does not turn on in the operating mode, it does not respond to the remote control.
Repair or diagnostics of the EAX65610905 motherboard should begin by checking the stabilizers and power converters needed to power the chips and matrix. If necessary, update or replace the software (software). In cases of complex repairs of MB (SSB) and in the presence of the necessary skills and equipment, sometimes it may be necessary to replace its EEPROM chips: 24C256, SOUND: Audio: NTP7513, D9PXV, D9PTK, 100GEA, TPA6138 and other possible faulty components. Malfunctions associated with the application of BGA soldering technologies are usually easily diagnosed by the heating method.
Malfunction of the tuner TDJM-G101D is established after checking the software and all supply voltages at its terminals. The data exchange of the tuner with the processor via the I2C bus can be controlled by an oscilloscope.
Attention TV owners! Attempts at self-repair of LG 32LB572U are not recommended by the manufacturer and can lead to serious negative consequences!
Service manual and schematic diagram ---------------------> LG 32LB572U Chassis LE46B
85 pages of 2014 on models 32LB5700, 32LB570U, 32LB570V, 32LB572U, 32LB572V -Z *
You can reduce the backlight current in LG TVs with LGP32-14PL1 power supplies (EAX65391401) as follows. The current sensor consists of six resistors R816-R821 connected in parallel - 1 Ohm, 1 Ohm, 1 Ohm, 1 Ohm, 2 Ohm, 8.2 Ohm. The total resistance in this case will be 0.22 Ohm. If you remove one resistor 1 Ohm, the total resistance increases to 0.28 Ohm, the current decreases proportionally from 250 mA to about 190 mA.
More details on this page
The appearance of the MainBoard EAX65610905 is shown in the figure below:EAX65610905
EAX65610905 can be used in TVs:
LG 47LB580V (Panel LC470DUE (FG)(A4)), LG 42LB572V (Panel LC420DUE (FG)(A4)), LG 32LF580U 32LF580U-ZA.ARUWLDU (Panel NC320DXN VSBP5), LG 32LB572U (Panel NC320DXN VSBP2).
The appearance of the power supply
Main features of the device LG 32LB572U:
Installed matrix (LED-panel) NC320DXN VSBP2.
To power the backlight LEDs, a converter is used, combined with a power supply unit, controlled by a PWM controller SSC1S311, A27RAE. As the power elements of the LED driver, keys of the type STD11N65M5, MDHT4N20Y are used.
The necessary supply voltages for all nodes of the LG 32LB572U TV are generated by the LGP32-14PL1 power module or its analogs using NCP1251 (PWM SOT23-6), NR134S microchips and KP8N65 type power switches.
MainBoard - the main board (motherboard) is an EAX65610905 module, using EEPROM chips: 24C256, SOUND: Audio: NTP7513, D9PXV, D9PTK, 100GEA, TPA6138 and others.
The TDJM-G101D tuner provides television reception and channel tuning