描述 Description

The LM3414 and LM3414HV are 1-A 60-W

common anode-capable constant current buck LED drivers. They are suitable for driving single string of 3-W HBLED with up to 96% efficiency. They accept input voltages from 4.5 VDC to 65 VDC and deliver up to 1-A average LED current with ±3% accuracy. The integrated low-side N-channel power MOSFET and current sensing element realize simple and low component count circuitry, as no bootstrapping capacitor and external current-sensing resistor are required. An external small-signal resistor to ground provides very fine LED current adjustment, analog dimming, and thermal fold-back functions.

Constant switching frequency operation eases EMI. No external loop compensation network is needed. The proprietary Pulse-Level-Modulation (PLM) control method benefits in high conversion efficiency and true average LED current regulation. Fast response time realizes fine LED current pulse fulfilling the 240 Hz 256-step dimming resolution requirement for general lighting.

The LM3414 and LM3414HV are available in SOIC-8 and 3 mm × 3 mm WSON-8 packages.

特性 Features

? Supports LED Power up to 60 W
: 18x 3-W HBLEDs
? RequiresNo External Current Sensing Resistor
? ±3% LED Current Accuracy
? Up to 96% Efficiency
? High Contrast Ratio (Minimum Dimming Current Pulse Width 1000 mA
? Support Analog Dimming and Thermal Fold-Back
? Wide Input Voltage Range:
? 4.5 V to 42 V (LM3414)
? 4.5 V to 65 V (LM3414HV)

? Constant Switching Frequency Adjustable from 250 kHz to 1000 kHz
? Thermal Shutdown Protection
? Power Enhanced SOIC-8 or 3 mm × 3 mm WSON-8 Package