The LM3409, LM3409-Q1, LM3409HV, and LM3409HV-Q1 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 and fast output enable/disable function and a thermally enhanced 10-pin, HVSSOP package. These features combine to make the LM3409 family of devices ideal for use as constant current sources for driving LEDs where forward currents up to 5 A are easily achievable.
The LM3409 devices use 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.
For all available packages, see the orderable addendum at the end of the data sheet.
LM3409-Q1 and LM3409HV-Q1 are Automotive Grade Products: AEC-Q100 Grade 1 Qualified
2-Ω, 1-A Peak MOSFET Gate Drive
VIN Range: 6 V to 42 V (LM3409, LM3409-Q1)
VIN Range: 6 V to 75 V (LM3409HV, LM3409HV-Q1)
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 Capacitor-less Outputs
