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.