The new AS1163 SAID intelligent LED driver provides a connection for any LED to an OSP automotive interior or exterior lighting network

The Open System Protocol (OSP) is a simple, open network technology for connecting LEDs, sensors, actuators and other devices in a car. Developed by ams OSRAM, the OSP is available for use completely free, with no license or royalties, by any manufacturer of LEDs or other devices. It’s particularly suitable for connecting hundreds of low- or mid-power LEDs in a dynamic lighting system, an increasingly popular option for automotive interior ambient and exterior lighting.


Make interior vehicle lighting easier with a Stand-Alone Intelligent Driver (SAID)

The world’s first OSP-compatible LED was the OSIRE® E3731i, an intelligent RGB LED with integrated driver. Now ams OSRAM has introduced a stand-alone OSP LED driver which enables any other low- or mid-power LED to behave as though it were directly connected to an OSP network. This means that manufacturers of automotive lighting systems can build OSP lighting networks without needing to use LEDs that have OSP connectivity built-in – and without the need for a local microcontroller to provide the OSP functionality. By avoiding the need to add local microcontrollers, this new stand-alone driver makes it easier to implement over-the-air (OTA) firmware updates – an important feature of new software-defined vehicle architectures.

The new driver, the AS1163, is known as a Stand-Alone Intelligent Driver (SAID). It has nine output drivers, so a single SAID chip can drive three RGB LED channels. The chip’s intelligence is in its OSP networking capability. The driver implements commands for dynamic lighting effects transmitted over the OSP network from the host controller – the driver can adjust brightness at 16-bit resolution (equivalent dynamic range), 15-bit resolution (PWM 500Hz), or 14-bit resolution (PWM 1000Hz).AS1163 drivers can operate alongside OSIRE® E3731i LEDs in the same application.

The SAID enables more flexibility

But as well as driving RGB or single-color/white LEDs (both toplookers and sidelookers), each SAID device can also provide a bridge to the OSP network for any component, such as a sensor or actuator, that has an I2C interface. So now automotive manufacturers can build a complete OSP network with just a single host microcontroller, and with multiple SAID devices providing OSP connectivity for any low- or mid-power LEDs, and any I2C devices such as sensors, actuators or memories. An OSP network (which is compatible with a physical CAN bus) can connect up to 1,000 nodes at a maximum data rate of 2.4 Mbps in a two-wire daisy-chain configuration.

The AS1163 is ideal for automotive interior lighting systems, which are typically assembled as long thin strips of LEDs: it is supplied in a slim 16-lead QFN package with a 3 mm x 3 mm footprint, ideal for instance in a lightbar assembled on a single-layer PCB. It has adjustable output current options from 1.5 mA to 48 mA (CH0) or 24 mA (CH1, CH2) per driver for low-power LEDs. Output clustering enables it to provide a single output of up to 288 mA for a mid-power LED. This means that the AS1163 can support automotive exterior as well as interior lighting applications. 

Automotive lighting designers can evaluate the AS1163 intelligent driver with the SAID Demonstrator Board, available via all authorized ams OSRAM sales channels from June 2024.