Encoder node CAN bus interface hardware components！

Encoder node CAN bus interface hardware components
CAN bus interface mainly has the monolithic integrated circuit, the CAN main line controller, the CAN main line driver and the photoelectricity isolation and so on hardware composition. CAN bus communication interface specific circuit shown in Figure 3.

MCU select Intel80C196KC, it is a 16-bit embedded microcontroller, more suitable for complex real-time control of occasions, it is also responsible for the encoder data processing and initialization of the CAN bus node. CAN controller selects SJA1000 of Philips semiconductor company, realizes the interface of data communication between the bus and the host computer (control computer), supports CAN2.0A and CAN2.0B agreement, has the expansion 64 bytes to receive the buffer, support first in first out (FIFO) principle, support 11 and 29-bit identification code, communication bit rate up to 1Mbps, can work in BasicCAN mode and PeliCAN mode. CAN bus driver selection Philips TJA1050, which is a high-speed encoder CAN bus driver, CAN controller and the physical bus to provide the interface between the CAN bus to achieve differential transmission and reception functions, with strong electromagnetic interference, wide common-mode range Differential receive capability, input levels compatible with 3.3V devices, and un-powered nodes that do not interfere with the bus. Join the TJA1050 to ensure high-speed data communications. In order to improve the anti-interference ability and security, TJA1050 symmetry performance characteristics, the use of separation terminals. CANH and CANL and parallel to the ground between the two 30pF small capacitors, filter on the high-frequency interference on the bus and a certain degree of anti-electromagnetic radiation. In order to further improve the anti-jamming capability of the system, CAN controller SJA1000 and CAN driver TJA1050 used between the high-speed optocoupler 6N137 constitute isolation circuit to achieve current isolation connection, 6N137 both sides of the power supply VCC and VDD completely isolated, so to prevent line Between the two sides of the bus to connect two 120Ω bus impedance matching resistor.

Previous：Roundss camshaft position sensor absolute Angle encoder multiturn turn RDE108T36
Next：5U linear encoder position sensor 3m measuring for CNC machine tools