Pin Upd | Mp3378e Protection

The most stable way to bypass false-positive protection triggers without damaging the IC is to artificially clamp the OVP pin feedback loop. MP3378E - Monolithic Power Systems

MP3378E | Backlight Drivers (WLED) | 4-Channel WLED Controller And High Efficiency Buck Converter with EN pin | MPS | Monolithic Power Systems

controls the backlight engine, while EN2 switches the buck converter. Pulling EN1 below 0.6V resets the WLED controller latch after a protection event. 3. Why the Backlight Enters Protection Mode

Monitors and limits current to prevent damage from short circuits. LED Open and Short Protection: mp3378e protection pin upd

If one or more of the 4 strings have a broken trace or failed diode, the corresponding LED pin (Pins 25–28) will read anomalously high or float to a flat zero before the shutdown occurs. 2. Checking Resistor Dividers

Inputs for the four LED strings, which can handle voltages up to Protection Pin Update (Deprotection)

A shifting value in the upper resistor of the OVP voltage divider can trick the MP3378E into registering an over-voltage state even if the true boost voltage is safe. Measure the precision SMD resistors connected between the boost output rail and Pin 9. The most stable way to bypass false-positive protection

: If the screen flashes for a fraction of a second and shuts off, monitor the OVP pin voltage with an oscilloscope. If it climbs rapidly to its threshold before shutdown, an open circuit exists in one or more WLED strings.

The is a versatile, single-chip integrated circuit designed by Monolithic Power Systems (MPS) for liquid crystal display (LCD) monitor applications. It combines a 4-channel White LED (WLED) controller for backlighting with a high-efficiency buck converter for internal system power.

The MP3378E has an established reputation in the repair community, particularly as a common failure point in LG monitors. A classic sign of a failed MP3378E is a monitor that goes completely dark (no backlight) while the power LED remains lit. The root cause is often an internal short on the chip's 12V supply rail. This is confirmed by online discussion where technicians have found of the MP3378E is shorted to ground, which carries the 12V supply voltage for the internal buck converter. mp3378e protection pin upd

Detects if an LED string is disconnected or short-circuited.

For exact voltage thresholds and resistor calculations, refer to the MP3378E Datasheet from Monolithic Power Systems . If you'd like to troubleshoot a specific issue, tell me: