MP3387A 3-26V, 20kHz White LED Driver QFN-24

MP3387A 3-26V, 20kHz White LED Driver QFN-24

The MP3387A is a step-up converter with 6- channel current sources designed to drive white LED arrays for backlighting in mid- to large- sized LCD panels.

Key Specifications

Features

• 6-String, Max 80mA/String
• 3V to 26V Input Voltage Range
• 1.5% Current Matching Accuracy between Strings
• Programmable Switching Frequency
• Selectable Combined Analog and PWM Dimming Mode or Direct PWM Dimming Mode
• Combined Analog and PWM Dimming Mode with 25% Dimming Transfer Point
• 24kHz to 27.5kHz Output Dimming Frequency to Eliminate Audible Noise
• Cascading Capability with a Single Power Source
• Programmable Over-Voltage Protection (OVP)
• Recoverable Thermal Shutdown Protection

Typical Application Circuit

Applications

• Notebook PC
• Small LCD TV
• Handheld Terminal Display

Design Notes

• Channel-to-channel current matching sets backlight uniformity; check the matching spec at the current you will actually run.
• In boost topologies the OVP threshold must clear the worst-case forward voltage of the longest string, including temperature and binning spread.
• Keep PWM dimming above 200 Hz to stay clear of visible flicker, and away from the audio band if the product has a speaker.
• Size the inductor and output capacitor for the string current ripple, not the total LED current.

Common Questions