The MP3378E is housed in a 28-pin TSSOP package with an exposed pad for heat dissipation. Primary Function
If you want, I can:
If an LED string becomes open-circuit, the output voltage will rise; the OVP pin detects this spike and shuts down the external MOSFET to prevent component failure.
In many contemporary WLED controllers like the MP3378E, the term "protection pin" often refers to the pin or the COMP (Compensation) pin, which are critical for maintaining feedback loops. For users upgrading from older models (such as the MP3398 series), the addition of an explicit protection pin serves to:
When designing a system that uses the MP3378E, several design considerations should be taken into account to ensure safe and reliable operation:
The MP3378E’s internal gate driver for the boost MOSFET requires a stable VCC (typically 5V) and bootstrap voltage. If the bootstrap capacitor (C_BST) is degraded or the VCC capacitor near the IC has high ESR: mp3378e protection pin upd
: While primarily for setting the LED current, this pin also detects faults. An open or shorted ISET resistor will trigger protection mechanisms to disable the WLED driver.
Protects the chip from overheating. The Role of the "UPD" or Fault Detection Circuitry
If you need to reduce the current to extend the life of new LEDs (a common "update" after repair), you can increase the resistance of the resistor connected to the . This lowers the current across all four strings. MP3378E - Monolithic Power Systems
Once you’ve identified the root cause, here are proven remedies.
Detects if any of the 4 strings are not functioning correctly. The MP3378E is housed in a 28-pin TSSOP
Once a PROT fault occurs (OVP or under-voltage lockout on PROT), the MP3378E enters .
is triggered when the MP3378E detects a potential fault condition (e.g., rising output voltage or current mismatch) but the expected protection response (e.g., PWM dimming cycle termination or soft-start reset) does not occur within a predefined timing window. In essence, UPD indicates that the protection pin is receiving a fault signal under the threshold for normal shutdown, creating an ambiguous logic condition.
| Component | Value | Function | | :--- | :--- | :--- | | (pin 20) | 22nF – 47nF | Start-up delay / filter | | R_TOP (OVP) | 200kΩ – 1MΩ | Sets VOUT OVP | | R_BOTTOM (OVP) | 10kΩ – 47kΩ | Ground reference | | R_PROT (series) | 1kΩ – 10kΩ | Optional: limits current to pin |
The WLED controller includes multiple layers of protection to ensure robust operation in monitor backlighting applications.
Monitored via Pin 9; triggers when output exceeds set threshold. For users upgrading from older models (such as
The MP3378E features extensive protection to prevent catastrophic failure of the backlight system, including:
The is a highly integrated 4-channel WLED controller designed for LCD backlighting, commonly found in monitors and flat-panel displays. A critical part of its reliability is the Over-Voltage Protection (OVP) pin, which serves as the primary "protection pin" for monitoring output stability and preventing hardware failure. Key Functions of the Protection (OVP) Pin
The "UPD" in your search most likely refers to a In modern display driver ICs like the MP3378E, parameters such as the over-voltage protection (OVP) threshold and switching frequency are not hardwired. Instead, they are configured by the system's main processor (SoC) via a communication bus like I2C or SPI. This process is called a firmware update , and it is fundamental to the IC's operation.
26 May 2017 — * MP3378E. * WLED Controller: * Buck Converter: * WLED Controller. VIN1 .............................................. - 0.3V to + Mouser Electronics MP3378E - Monolithic Power Systems