Technical description and composition of the LG 32LB570U TV, panel type and applicable modules. The composition of the modules.LG LED
Model: 32LB570U 32LB570U-ZJ
Chassis / Version: LE46B / LD46B
Panel: NC320DXN VSBP2
T-CON: 3Z-2016372N
LED driver (backlight): integrated into PSU
PWM LED driver: SSC1S311
MOSFET LED driver: STD11N65M5, MDHT4N20Y
Power Supply (PSU): LGP32-14PL1 EAX65391401 (2.6)
PWM Power: NCP1251 (PWM SOT23-6 5A2R ..), NR134S
MOSFET Power: KP8N65
MainBoard: EAX65610904 (1.0)
IC MainBoard: H5TQ4G63AFR, EEPROM: 24C256, SOUND: Audio: NTP7513
Tuner: TDJM-G101D
Specifications 32LB570U
LG 32LB570U
General repair guidelines for TV LCD LED
Possible manifestations of defects
- The LG 32LB570U TV does not turn on at all. The control lights do not light or flash. The TV on the remote control and the control panel buttons do not respond.
Typically, with such manifestations, the defect is caused by faulty elements in the main power module LGP32-14PL1. It is necessary to measure the output voltages in its secondary circuits, and if they are completely absent, check the serviceability of the power switches (KP8N65) and rectifier diodes for possible breakdown (short circuit).
In case of breakdowns of semiconductors in the secondary circuits of any converter, as a rule, it can operate in emergency short-circuit mode without output voltages, and during short circuit in the elements of the primary circuit, the main fuse and, less often, the current sensor at the source of the key are most often cut off.
The breakdown of Mos-Fet keys used in pulsed sources is often caused by malfunctions of other elements, for example, in the power supply circuit of a PWM controller, in frequency-setting or damping circuits, as well as in Negative Stabilization Feedback. PWM chips NCP1251 (PWM SOT23-6 5A2R ..), NR134S are usually checked by replacing with new ones, or obviously working.
- There is no image, there is sound, it is responding to the remote control. Or immediately after turning on for a second, the image may appear and immediately disappear.
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 TV does not turn on, does not respond to the remote control. The indicator blinks or signals standby mode.
Repair or diagnostics of the EAX65610904 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). Sometimes they require checking or replacing (if necessary) the elements of the MainBoard board - H5TQ4G63AFR, EEPROM: 24C256, SOUND: Audio: NTP7513. In cases where the BGA processor is used, its malfunction is usually detected by the local heating method.
If there is no reception of television channels, but the TV is working properly from external devices, first of all it is necessary to check the power supply to the TDJM-G101D tuner and update the software. The pulses from the I2C bus must be controlled with an oscilloscope.
Attention TV owners! Self-repair attempts by LG 32LB570U are not recommended by the manufacturer and can lead to serious negative consequences!
Service manual and schematic diagram -------------------------> LG 32LB570U Chassis LD46B.
CHASSIS : LD46B; MODEL : 32LB57**, 32LB57**-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 EAX65610904 is shown in the figure below:EAX65610904
EAX65610904 can be used in TVs:
LG 32LB582V ZG (Panel LC320DUE (FG)(A4)), LG 42LB570V (Panel LC420DUE (FG)(A4)), LG 42LB5800 (Panel LC420DUE (P6)(A4)), LG 42LB580V (Panel LC420DUE (FG)(A4)), LG 32LB570U 32LB570U-ZJ (Panel NC320DXN VSBP2), LG 39LB580V (Panel T390HVF02.0 HC390DUN-VCHS1), LG 32LB580V ZB (Panel LC320DUE (FG)(A4)).
The appearance of the power supply
Main features of the device LG 32LB570U:
Installed matrix (LED-panel) NC320DXN VSBP2.
The matrix control uses the Timing Controller (T-CON) 3Z-2016372N.
To power the backlight LEDs, a converter is used, combined with a power supply unit, controlled by the PWM controller SSC1S311. 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 32LB570U TV are generated by the LGP32-14PL1 power supply module or its analogs using NCP1251 microcircuits (PWM SOT23-6 5A2R ..), NR134S and KP8N65 type power switches.
MainBoard - the main board (motherboard) is an EAX65610904 module, using H5TQ4G63AFR microcircuits, EEPROM: 24C256, SOUND: Audio: NTP7513 and others.
The TDJM-G101D tuner provides television reception and channel tuning.