Mp3378e Protection Pin Upd ((hot)) (2027)

If the internal OVP of the MP3378E (e.g., 80V) is too high for your LEDs, use a resistor divider from the boost output to UPD via a Zener diode.

: If an LED string shorts out, the voltage on its corresponding VLED pin will spike. If it drops too low, an open circuit is detected. The IC cross-references these channels and will trip the latch if it detects a stark mismatch exceeding the 2.5% matching threshold. Diagnosing Backlight Failures and Latch Protection

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

When a television or monitor turns on, displays an image for 1 to 5 seconds, and then goes dark while audio or flashlight-visible graphics remain, the MP3378E has entered protection mode. This typical failure loop occurs for three main reasons: mp3378e protection pin upd

Detects faults in individual LED strings .

This pin samples the boosted output voltage via a resistive voltage divider network. If the feedback voltage surpasses the internal reference threshold (typically due to an open LED string where the boost converter aggressively overcompensates), the IC immediately latches off the gate driver channel to prevent component explosion. 2. The LED1 to LED4 Channels

MP3378E Protection Loop +-----------------------+ | MP3378E | VOUT (Boost) --->| OVP Pin (Overvoltage) |---> Shuts down GATE pin | | LED Cathodes --->| LED1-4 Pins (Open/Sh) |---> Disables faulty string | | Inductor/FET --->| ISENSE Pin (OCP) |---> Caps max duty cycle +-----------------------+ 1. The OVP Pin (Over-Voltage Protection Input) The directly checks the boost output voltage ( VOUTcap V sub cap O cap U cap T end-sub ) via an external resistor divider network. If the internal OVP of the MP3378E (e

: The voltage on this pin stays safely below its internal threshold (typically 1.23V).

Protects the chip from overheating. The Role of the "UPD" or Fault Detection Circuitry

In repair contexts, a "protection pin update" usually refers to disabling these safety features to diagnose if the IC itself is faulty or if the issue lies in aging LED strips that are triggering the protection unnecessarily. Common Modification / "Update" Global Protection The IC cross-references these channels and will trip

The MP3378E protection pin is a compact but powerful interface that encapsulates critical safety and fault-management behavior of the regulator. Proper handling requires careful reading of the device’s datasheet and errata for revision-specific changes (UPD), robust PCB and thermal design, appropriate pull-up and filtering choices, and thorough fault-mode testing. By integrating the PROT pin correctly—using conservative pull-ups, transient protection, and clear firmware strategies—designers can ensure safe, reliable power delivery and predictable system behavior under fault conditions.

This public link is valid for 7 days and shares a thread, including any personal information you added. This link or copies made by others cannot be deleted. If you share with third parties, their policies apply. Can’t copy the link right now. Try again later. MP3378E - Monolithic Power Systems

This pin monitors the output voltage of the boost converter. If a string of LEDs becomes "open" (disconnected), the output voltage will rise rapidly as the controller tries to maintain constant current. The OVP pin prevents this by triggering a shutdown when the voltage exceeds a programmed threshold, typically set via an external resistor divider.

MP3378E Protection Pin UTP/OVP/UVP: Understanding and Troubleshooting the MP3378E Protection Pins

: If the voltage at the OVP pin exceeds a preset internal threshold, the IC shuts down the PWM generator and disables the MOSFET drivers to prevent thermal runaway or component damage. : This protects against open-circuit