Integrated LED driver IC sends right signals for motorcycle design
Reducing board area and design effort for LED lamp applications, the BD183x7EFV-M (BD18337EFV-M / BD18347EFV-M) series LED drivers incorporate a proprietary thermal dissipation circuit and individual LED control function. According to Rohm, the four-channel linear LED driver IC with MOSFET is suitable for LED rear lamps (indicator and brake lights), fog lamps and indicator signals for automotive use.
They have been developed in response to vehicle manufacturers’ demands for simpler circuits for rear and license plate lamps in order to reduce costs and shorten development time. To minimise board area, output channels are consolidated into a single terminal, allowing a configuration of a four-channel, high output (150mA per channel) driver into a compact 16pin package.
The individual LED control function allows driving LED lamps with different specifications by one driver. To reduce design effort, heat distribution circuit allows simplification of the overall thermal design. The LED control function enables individual or collective control of LEDs in case of errors, to comply with motorcycle standards for licence plate lighting. Individual dimming function supports sequential lighting for greater design versatility along with protection functions to protect the LED driver and peripheral circuits.
Rohm’s heat distribution circuit consolidates the heat dissipation terminals into one to achieve 150mA per channel in a compact 16pin form factor while increasing the maximum number of channels to four. In conventional vehicle rear-lamp systems, 2 LED drivers are needed to power 4 LED strings. ROHM’s new ICs make it possible to drive all 4 strings with just one driver, significantly reducing the number of parts along with mounting area.
The LED individual control function drives two LED lamps with different specifications, minimising board area by reducing the number of ICs required to drive the same number of LEDs.
The BD183x7EFV-M series incorporates a thermal distribution circuit that consolidates the multiple heat dissipation circuit terminals into one. According to Rohm this reduces design effort by allowing thermal design typically required for each channel to be completed in a single design step.
The built-in control function allows users to select either collective or individual LED off, in case a lamp fails to light up. Designers can select to turn all LEDs off or only the failed string to comply with multi-regional laws with a single setting. This reduces the number of redesign hours “considerably”, says the company.
The BD183x7EFV-M series provides an individual dimming function for sequential lighting by adding external resistors. There are also built-in protection features, such as open/short detection for vehicle lamps and abnormality detection for each channel.
