Overview
The IS32LT3177 and IS32LT3178 are adjustable
linear current devices with excellent temperature
stability. A single resistor is all that is required to set
the operating current from 10mA to 200mA. The
devices can operate from an input voltage from 2.9V
to 40V with a minimal voltage headroom of 1.0V
(Typ.) at 150mA. Designed with a low dropout
voltage; the device can drive LED strings close to
the supply voltage without switch capacitors or
inductors.
The IS32LT3177/78 simplifies designs by
providing a stable current without the additional
requirement of inductors, FETs or diodes. The
complete constant current driver requires only a
current set resistor and a small PCB area making
designs both efficient and cost effective.
The EN Pin of the IS32LT3177 can be tied to VBAT
or PSM (Power Supply Modulation) signal for high
side dimming. The EN Pin of the IS32LT3178 can
function as the PWM signal input used for MCU
PWM dimming.
As a current sink it is ideal for LED lighting
applications or current limiter for power supplies.
The device is provided in a lead (Pb) free, SOT23-6
and SOP-8-EP packages.