Texas Instruments’ DP83TC811S-Q1 100Mbps Ethernet PHY (see figure 2) is compatible with multiple independent multimedia interfaces and includes a comprehensive diagnostic toolkit to detect issues such as broken cables and ESD strikes as well as temperature and voltage variations.
Microchip’s KSZ9031RNX (block diagram in figure 2) is a 10BASE-T/100BASE-TX/1000BASE-T capable Ethernet PHY that has been optimised for modern automotive applications. The device is housed in a 48-pin, lead-free QFN package, and achieves a maximum data rate of 1 Gbps with an auto-negotiation mechanism that automatically selects the fastest possible link-up speed. An integrated LDO voltage controller supports the 1.2 V core through driving a low cost MOSFET.
Another 1 Gbps device is Broadcom’s BCM89610 10BASE-T/100BASE-TX/1000BASE-T PHY (see Figure 4) that includes industry leading noise cancellation and jitter performance. As a result, this device is capable of being used with a broad range of cable qualities, offering potentially significant cost savings.
Summary
Vehicles are becoming an IT challenge with vast amounts of data being captured and created, all of which needs to be processed and transmitted around the vehicle. As more systems are added and existing functions expand, through higher resolution cameras for example, so greater bandwidth and data rates are required.
Older protocols are showing their age and newer protocols developed to be the next generation have not been widely adopted, leading the automotive industry to seek a new solution that is fast, low latency and low cost.
Ethernet is coming to the fore as it meets all of the technical requirements as new versions have been developed for automotive use. It also benefits from an existing ecosystem that includes software, tools and a wide array of low-cost, mass produced components. Possibly Ethernet’s most important attribute is its ability to be developed to meet the multi-Gigabit/second needs of the future.
