Electronics Weekly Electronics Design & Components Tech News
BD18336NUF-M is a 3 x 3 x 1mm constant current driver IC that can deliver 400mA continuously (600mA at 50% duty cycle) into a string of three white LEDs or parallel strings of LEDs.
“Heat generated by the LEDs is suppressed by an integrated current de-rating function,” according to Rohm. “The thermal adjustable output current limits the heat generated by the LEDs, increasing their lifetime, which makes the LED driver ideal for white as well as for red and yellow LEDs.”
As well as thermal de-rating to increase reliability, protections include LED open detection, output short circuit protection, SET pin short circuit protection (see diagram), over-voltage mute, current bypass at reduced voltage, fault flag output. Not all protection operates with parallel strings of LEDs.
Output current is resistor-programmable, and there is a built-in PWM oscillator that works with an external RC to adjust the waveform, or an external PWM signal can be applied.
Application: 387mA to three white LEDs, 10% duty cycle (300Hz)
Operation is across -40 to +150°C, and there is an external thermistor connection.
Operation is also across 5.5 – 20V (survival to 42v), although the LEDs need around 9V to function properly.
Packaging is VSON10FV3030, and the chip is qualified to AEC-Q100 Grade 1.
Applications is expected in automotive socket-type LED lamps such as for rear lamps, turn indicators, fog lamps, position lamps or daylight running lamps.
“ROHM is embracing the market trend towards miniaturisation with its newest LED driver without compromising in safety features and performance,” said Rohm marketing manager Stefan Drouzas.
