LM3409HV

LM3409 / LM3409HV PFET Buck Controller for High Power LED Drives www.DataSheet4U.com LM3409 LM3409HV June 12, 2009 PFET Buck Controller for High Power LED Drives 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. 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 Au...