Taiwan Semiconductor's DC / DC automotive LED driver chip can be configured to run in Boost, Buck-Boost, and SEPIC topology, from a supply voltage between 4.5 V and 42 V...
Taiwan Semiconductor's DC / DC automotive LED driver chip can be configured to run in Boost, Buck-Boost, and SEPIC topology, from a supply voltage between 4.5 V and 42 V.
The output of the chip TS19501CB10H is current regulated and can be used to drive a chain of LEDs such as vehicle headlights, turn indicators, fog lights etc. The controller can be operated in boost, buck-boost or SEPIC mode and provides full protection and diagnostics. The average (undimmed) output current is 150 mV / Rcs. (where 150 mV is the internal reference voltage, and Rcs the value of sense resistor). The single LED shown represents a chain of LEDs.
The maximum output current depends on the rating of the external MOSFET used. According to the datasheet, the driver achieves a rise time of 40 ns for a 14 V supply with a capacitive load of 1 nF. The converter frequency can be set by RT to values between 70 and 700 kHz. The use of jitter on the switching signal ensures interference energy is spread over a wide frequency band (spread spectrum) to reduce the average EMC generated.
For dimming, the IC can set the output current using an analogue control voltage (0 to 1.6 V) or directly by applying a digital PWM signal from 0 to 100%. The pin supplies 10 microamps so that a variable resistor to ground (such as an NTC thermistor) can be used to supply this control signal.
Errors are signalled via the open-drain fault flag pin. The IC provides protection against input under-voltage, output overvoltage and output short circuit. The chip is supplied in a MSOP-10EP package.
