LM3409MY PFET Buck Controller transistor integrated circuit for High Power LED Drives

PFET Buck Controller for High Power LED Drives

Features

■ 2Ω, 1A Peak MosFET Gate Drive

■ VIN Range: 6V to 42V (LM3409)

■ VIN Range: 6V to 75V (LM3409HV)

■ Differential, High-side Current Sense

■ Cycle-by-Cycle Current Limit

■ No Control Loop Compensation Required

■ 10,000:1 PWM Dimming Range

■ 250:1 Analog Dimming Range

■ Supports All-Ceramic Output Capacitors and Capacitorless Outputs

■ Low Power Shutdown

■ Thermal Shutdown Protection

■ Thermally Enhanced eMSOP-10 Package

Applications

■ LED Driver

■ Constant Current Source

■ Automotive Lighting

■ General Illumination

■ Industrial Lighting

General Description

The LM3409/09HV are P-channel MosFET (PFET) controllers for step-down (buck) current regulators. They offer wide input voltage range, high-side differential current sense with low adjustable threshold voltage, fast output enable/disable function and a thermally enhanced eMSOP-10 package.

These features combine to make the LM3409/09HV ideal for use as constant current sources for driving LEDs where forward currents up to 5A are easily achievable. The LM3409/09HV uses Constant Off-Time (COFT) control to regulate an accurate constant current without the need for external control loop compensation. Analog and PWM dimming are easy to implement and result in a highly linear dimming range with excellent achievable contrast ratios.

Programmable UVLO, low-power shutdown, and thermal shutdown complete the feature set.

Typical Application