In previous reports, we covered 10BASE-T1S and 10BASE-T1L Single Pair Ethernet chips from Microchip and Analog Devices that facilitate Ethernet communication over a single twisted-pair cable. However, these devices integrate a full Ethernet PHY or MAC-PHY directly.
NXP introduces a novel approach with the TJA1410 (automotive) and TJF1410 (industrial) Physical Medium Dependent transceivers. These PMDs separate the analog physical layer from the digital Ethernet logic. By embedding the digital PHY portion into the host microcontroller or switch, the TJA1410 and TJF1410 focus on essential analog functions for transmitting and receiving signals. They leverage a 3-pin OPEN Alliance interface for host communication.
Specifications for the TJA1410 and TJF1410 PMD transceivers include:
– Networking: 10BASE-T1S compliant with IEEE 802.3cg and OPEN Alliance TC14, TC10
– Host Interface: 3-pin OA interface (requires a host with a 10BASE-T1S digital PHY)
– Data Rate: 10 Mbps multi-drop Ethernet
– Miscellaneous:
– Up to 32 nodes on a single 10BASE-T1S bus (TJF1410)
– Cable length up to 100 meters
– OPEN Alliance TC10 / TC14 wake-up signaling
– Local and remote wake-up
– Advanced diagnostics like topology discovery
– Power:
– 3.3V operation (not explicitly stated)
– Low quiescent current
– Compatible with Power over Data Line (PoDL)
– Package: 8-pin HVSON8 (3 x 3 mm)
– Safety:
– ISO 26262 ASIL B compliant (Automotive variant only)
– AEC-Q100 Grade 1 qualified (Automotive variant only)
– ESD Robustness: ±8 kV HBM
– High EMC performance
NXP suggests that the TJA1410 works with affordable CAN components, potentially reducing system costs, while the TJF1410 can assist industrial systems in transitioning from Modbus or RS-485 to Ethernet networks where multiple devices utilize a single cable.
NXP provides Linux drivers for both devices and real-time software support, including AUTOSAR and non-AUTOSAR platforms. These transceivers are compatible with host MCUs or switches that integrate the 10BASE-T1S digital PHY, such as the S32K5, S32N7, and S32J100 series for automotive and the upcoming MCX A microcontroller series for industrial applications.
These chips’ multi-drop bus topology eliminates the need for expensive point-to-point switched Ethernet at the network’s edge, allowing multiple sensors, actuators, or zone controllers to connect on a single pair of wires. The TJA1410-EVB board offers a platform for evaluation.
Both the TJA1410 and TJF1410 are available in HVSON8 packages on the NXP store. The industrial TJF1410 variant is priced around $0.89 per unit for 1K orders, while the automotive-grade TJA1410 costs about $0.44 per unit for 1K orders. The TGA1410-EVB is available for pre-order at Mouser for $119.99. More details can be found in the press release.