Seiko Instruments S-5855A LED sensor

Seiko Instruments has released the S-5855A series, a PWM (pulse width modulation) output temperature sensor IC for LED lighting designs. The device begins to decrease the duty ratio of PWM signal output when the temperature exceeds the specified value.

This change in the duty ratio enables LED lighting circuits to avoid temperatures increasing above design limits.

The sensor is optimised for use in LED lighting systems for PC laptops, tablets and other devices. It can also be used with any system requiring temperature control. The device is connected to the DIM pin of an LED driver IC to control the LED luminance, enhancing safety protection and boosting efficiency.

It maintains 100% luminescence up to the specified temperature. Once this is exceeded, the sensor decreases the PWM output duty ratio gradually along with an increasing temperature. This enables the LED luminance to diminish gradually.