Intelligent 48-channel LED driver with scan matrix

Diodes Incorporated launched its new automotive-compliant AL5958Q matrix LED driver. With its 48-channel constant current source, capable of up to 32 scans, the device enables the automotive dynamic lighting revolution, bringing improved safety, personalisation, and aesthetics to new vehicle platforms.

The device is especially suited for narrow pixel mini- and micro-LED displays, which need multiple RGB LEDs to produce animated, dynamic lighting with data and information. Applications include central information displays, cluster displays, head-up displays, grill and emblem lights, body LED panels, interior lights, and rear lights.

The device includes built-in intelligent matrix display command functions that significantly reduce the processing overhead on the local MCU. These functions encompass automatic black-frame insertion to mitigate blurs induced by scanning switches, reduction of last scan and next scan-line ghost images to eradicate ghosting from parasitic capacitors, and suppression of short-LED caterpillars. Open-LED fail lines and staggered current output delay to minimise inrush current are included, as well as grayscale enhancement (also known as low-brightness uniformity compensation), a greyscale clock (GCK) watchdog timer, and sleep mode to deliver power savings.

The device’s differentiated capability is underscored by its integrated 16 N-MOSFET switches and scan control per device. This enables them to support static and dynamic systems, ranging from 0 scans to 32 scans, with a flexible scan sequence, allowing for animated lighting displays. For larger applications, multiple AL5958Q devices can be daisy-chained without limitation. This capability enables the creation of expansive and complex RGB displays while also facilitating local dimming.

The AL5958Q’s high 16-bit resolution dimming, coupled with its RGB support, delivers highly precise brightness control and colour mixing. The current output for each colour group can be configured either through three external current-sensing resistors or by programming three 6-bit global current control registers. Furthermore, the distinctive multiplex-pulse density modulation (M-PDM) technology improves the refresh rate of dynamic scanning systems without increasing the frequency of the greyscale (GCK) clock, thereby effectively mitigating EMI due to high clock frequencies.

The device features a comprehensive suite of advanced diagnostic capabilities and protection mechanisms, providing vital monitoring functions. These include error flag registers applied to LED open/short to read out each channel using open/short detection, UVLO protection, and a watchdog timer.

Operating across a -40C to +125C ambient temperature range, the AL5958Q is supplied in the wettable W-QFN9090-76/SWP (Type A1) package, which meets the requirements of the general automotive market.