SNLS589B September 2016 – July 2018 DS90UB960-Q1
The DS90UB960-Q1 is a sensor hub that aggregates up to four inputs acquired from a FPD-Link III stream and transmitted over a MIPI sensor serial interface (CSI-2). When coupled with DS90UB953-Q1, DS90UB935-Q1, DS90UB933-Q1, or DS90UB913A-Q1 FPD-Link III serializers, the DS90UB960-Q1 receives data streams from multiple imagers that can be multiplexed on the same CSI-2 links. When paired with the DS90UB953-Q1 or DS90UB935-Q1, the DS90UB960-Q1 operates with the full feature set. When in the backward-compatible mode paired with a DS90UB933-Q1 or DS90UB913A-Q1, the device operates with basic functionality. The DS90UB960-Q1 supplies two MIPI CSI-2 ports, configuration with four lanes per port with up to 1.664 Gbps per lane. The second MIPI CSI-2 output port is available to provide either more bandwidth or supply a second replicated output. The DS90UB960-Q1 can support multiple data formats (programmable as RAW, YUV, RGB) and different sensor resolutions. The CSI-2 Tx module accommodates both image data and non-image data (including synchronization or embedded data packets).
The DS90UB960-Q1 CSI-2 interface combines each of the sensor data streams into packets designated for each virtual channel. The output generated is composed of virtual channels to separate different streams to be interleaved. Each virtual channel is identified by a unique channel identification number in the packet header.
When the DS90UB960-Q1 is paired with a DS90UB953-Q1 serializer, the received FPD-Link III forward channel is constructed in 40-bit long frames. Each encoded frame contains video payload data, I2C forward channel data, and additional information on framing, data integrity and link diagnostics. The high-speed, serial bit stream from the DS90UB953-Q1 contains an embedded clock and DC-balancing ensuring sufficient data line transitions for enhanced signal quality. When paired with ADAS serializers in RAW input mode, the received FPD-Link III forward channel is similarly constructed at a lower line rate in 28-bit long frames. The DS90UB960-Q1 device recovers a high-speed, FPD-Link III forward channel signal and generates a bidirectional control channel control signal in the reverse channel direction. The DS90UB960-Q1 converts the FPD-Link III stream into a MIPI CSI-2 output interface designed to support automotive sensors, including 2MP/60fps and 4MP/30fps image sensors.
The DS90UB960-Q1 device has four receive input ports to accept up to four sensor streams simultaneously. The control channel function of the DS90UB953-Q1 / DS90UB960-Q1 pair supplies bidirectional communication between the image sensors and ECU. The integrated bidirectional control channel transfers data bidirectionally over the same differential pair used for video data interface. This interface has advantages over other chipsets because the interface eliminates the need for additional wires for programming and control. The bidirectional control channel bus is controlled through an I2C port. The bidirectional control channel supplies continuous low latency communication and is not dependent on video blanking intervals. The DS90UB953-Q1 / DS90UB960-Q1 chipset can operate entirely off of the back channel frequency clock generated by the DS90UB960-Q1 and recovered by the DS90UB953-Q1. The DS90UB953-Q1 provides the reference clock source for the sensor based on the recovered back channel clock. Synchronous clocking mode has distinct advantages in a multi-sensor system by locking all of the sensors and the receiver to a common reference in the same clock domain, which reduces or eliminates the need for data buffering and re-synchronization. This mode also eliminates the cost, space, and potential failure point of a reference oscillator within the sensor. The DS90UB953-Q1 / DS90UB960-Q1 chipset gives customers the choice to work with different clocking schemes. The DS90UB953-Q1 / DS90UB960-Q1 chipset can also use an external oscillator as the reference clock source for the PLL as the primary reference clock to the serializer (see the DS90UB953-Q1 data sheet).