Automotive LED headlamp driver meets temperature, EMI specs

July 28, 2016 // By Graham Prophet
Cypress Semiconductor’s automotive LED driver enables smaller and more cost-effective headlight systems; the S6BL112A automotive-grade LED driver is presented as the first to feature synchronous control for conversion efficiency, enabling stable performance in a lighting system.

The device is able to drive LEDs at a 2.1-MHz switching frequency, which enables a compact headlight solution that uses small, inexpensive inductors, reducing physical size and bill-of-materials costs. The LED drivers combine with Cypress’s Traveo microcontrollers (MCUs) and power management ICs (PMICs) to complete an automotive front-lighting solution.


The driver IC features an input voltage range of 4.5-42 V that encompasses extreme operating conditions such as cold-cranking to load dump. Safety functions include under current detection, over current and voltage protection, as well as the ability to mask undesired LED OPEN diagnosis during cold cranking. Synchronous operation eliminates unstable dimming that can occur when the input voltage is low.


The S6BL112A is a one-channel 2A output buck LED driver that supports both analogue and PWM dimming functions, enabling precise brightness control. Its switching frequency can be set between 205 kHz and 2.1 MHz, with high output current accuracy of ±2%. The device enables slew rate control without an external filter, limiting EMI generation. It is available in a 16-pin, thermally-enhanced TSSOP package.