Overview
The IS32LT3180 is an eight channel linear current
regulator for automotive rear tail light applications such
as RCL (Rear Combination Lamps) and CHMSL
(Center High Mounted Stop Lamps). It is fully
programmable with two LED brightness levels for the
different intensity requirements of “stop” bright (DC
mode) and “tail” dim (PWM mode).
A logic level at the PWM pin is used to select between
the tail and stop output conditions. The stop condition
provides the highest intensity output, while the tail
condition utilizes an internally generated PWM signal
to reduce the intensity of the LEDs’ light output.
The sink current at the OUTx pins is easily set with a
single resistor at the STOP pin. A second resistor at
the TAIL pin sets the duty cycle of the internal PWM
oscillator for dimming (less bright) the LED output
when operating in the tail condition.
An external FET controller is provided to maintain a
constant headroom and power dissipation for the LED
driver under wide varying supply voltages. For proper
operation without Fault trigger, the use of external FET
is recommended.
The IS32LT3180 is offered in an eTSSOP-16 package.