Compliant with the MIPI CSI-2 interface for video data, TI’s DS90UB935-Q1 offers a bandwidth of over 2.5 Gb/s for automotive applications.
By Murray Slovick, Contributing Editor
Together with a companion deserializer, Texas Instruments’ (TI) DS90UB935-Q1 automotive-rated serializer is targeted for connections between imagers and video processors in an electronic control unit (ECU). The serializer, part of TI’s FPD-Link III device family, is formulated to support high-speed, space-constrained data sensors including 2MP imagers at 60 frames/s and as well as 4MP, 30-frame/s cameras, radar, and LiDAR. It provides a high-speed forward channel and a low-latency, bidirectional control channel, and supports power over a single coax (PoC) or STP cable.
As ADAS applications such as front-camera and camera-monitoring systems use imagers above 2MP resolution, it increases video data-transfer speed requirements. This device is said to be well-suited for driving video data requiring up to 12-bit pixel depth plus two synchronization signals along with a bidirectional control channel bus.
The DS90UB35-Q1 supports ADAS and autonomous driving through diagnostic and data-protection features such as cyclic redundancy check (CRC) to detect accidental changes to raw data; sensor data integrity check; I2C write protection; voltage and temperature measurement; programmable alarm; and line fault detection. The DS90UB935-Q1 devices are AEC-Q100-qualified for automotive applications.
The part is compliant with the mobile industry processor interface (MIPI) CSI-2 interface for video data, offering a bandwidth over 2.5 Gb/s. The MIPI standard defines three unique physical-layer (PHY) specifications: MIPI D-PHY, M-PHY, and C-PHY.
MIPI D-PHY and C-PHY physical layers support camera and display applications, while high-performance camera, memory, and chip-to-chip applications are supported on top of the M-PHY layer. MIPI CSI-2 is a widely used camera interface that enables data-transfer rates as high as 832 Mb/s on each of the four CSI-2 differential lanes. As such, it can support a broad range of high-performance applications, including 1080p and 4K and 8K video.
The serializer features an operating temperature range of −40 to +105°C and comes in a compact 5- × 5-mm VQFN package. DS90UB935-Q1 devices include HBM ESD Classification Level 3A and CDM ESD Classification Level C6. HBM simulates when a discharge occurs between a human (e.g., hand/finger) to a conductor (e.g., metal rail). The model is a simulation of the discharge, which might occur when a human touches an electronic device. The Charge Device Model (CDM) characterizes the susceptibility of an electronic device to damage from electrostatic discharge (ESD).
Using TI’s embedded clock technology allows for full-duplex communication over a single differential pair, carrying asymmetrical-bidirectional control channel information. This single serial stream simplifies transferring a wide data bus over PCB traces and cable by eliminating potential skew problems between parallel data and clock paths. It ultimately saves system cost by narrowing data paths that, in turn, reduce PCB layers, cable width, and connector size and pins. Internal dc-balanced encoding/decoding is used to support ac-coupled interconnects.
The DS90UB933-Q1 device offers the flat-panel-display link 3, better known as FPD-Link III. This is an interface used in many automotive applications to transport video from point to point. The interface enables the transport of high-definition digital video, as well as a bidirectional control channel, over a low-cost cable, either twisted pair or coax.