CAN bus interface design diagram

LPC2368 integrates two CAN controllers compatible with CAN 2.0A/2.0B. Therefore, only one CAN
bus transceiver is needed to meet the design requirements. PCA82C250 is a CAN bus transceiver from Philips, which provides
high-speed differential transmission capability for the bus and high-efficiency differential reception capability for the CAN controller. In order to enhance
the anti-interference ability of the CAN bus node, the CAN controller outputs TX and RX of LPC2368 cannot be directly connected to the TX and RX of PCA82C250,
but are connected to PCA82C250 through high-speed optical coupler 6N137, thus achieving electrical isolation between the CAN nodes on the bus
. The isolation of the optical coupler power supply can be achieved through a low-power power isolation module or a switching power supply with a multi-5 V isolated output
. Although these parts increase the complexity of the node, they improve the stability and safety of the node [2]. The circuit of the CAN bus interface
is shown in Figure 2 (RD1 and TD1 in the circuit diagram are connected to pins 57 and 56 of LPC2368 respectively).

CAN bus interface design diagram