Monitored via Pin 9; triggers when output exceeds set threshold.
If the LEDs fail short, the VLED pin sees an instant surge in voltage. The IC pulls that channel out of operation to protect against cascading thermal destruction. 3. Over-Current Sense (ISENSE)
Based on the component naming convention, the typically refers to the Monolithic Power Systems (MPS) MP3378 , a popular 8-string WLED driver controller.
MP3378E | Backlight Drivers (WLED) | 4-Channel WLED Controller And High Efficiency Buck Converter with EN pin | MPS | Monolithic Power Systems
Mastering the MP3378E Protection: A Deep Dive into Backlight Controller Faults Monolithic Power Systems (MPS) MP3378E mp3378e protection pin upd
In the world of modern display technology—from ultra-thin laptops and automotive infotainment systems to high-brightness industrial monitors—the from Monolithic Power Systems (MPS) has emerged as a go-to solution for driving LED backlight strings. This 8-channel, boost-controlled LED driver is celebrated for its high efficiency, dimming accuracy, and built-in fault management.
MP3378E Protection Pin UPD: Deep Dive Guide to Over-Voltage Protection (OVP) and Backlight Diagnostics
If one string is significantly brighter or dimmer, the
Switching regulators must deliver stable output voltages while protecting themselves and the load from abnormal conditions such as short circuits, overcurrent, thermal stress, and output overvoltage. Dedicated protection pins provide hardware-level interfaces that expose these protection functions to system designers, enabling predictable interactions between the regulator and the rest of the system (for example, enabling external shutdown, signaling fault status to a microcontroller, or allowing configuration of threshold/response behavior). Monitored via Pin 9; triggers when output exceeds
Includes and recoverable thermal shutdown. Short Protection
If an entire LED string becomes open-circuit (broken PCB trace or broken LED), the voltage at the corresponding LED pin drops to zero (or very low). Since the current source cannot regulate current, the boost converter will increase $V_OUT$ to compensate.
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To set the maximum allowable output voltage, select the upper ($R_OVP_UP$) and lower ($R_OVP_LOW$) divider resistors using the formula: $$V_OUT_MAX = V_OVP_TH \times \left(1 + \fracR_OVP_UPR_OVP_LOW\right)$$ In many repair scenarios
The MP3378E includes several safety mechanisms that can trigger a shutdown: Monitored via the OVP pin .
In many repair scenarios, the serves as the primary "protection pin" that triggers a shutdown.
current matching accuracy might be compromised by a partial short in one string, which may not trigger the full 6.3V6.3 cap V LEDX_OV threshold but can cause uneven wear. MP3378E - Monolithic Power Systems