The scenario
Designing an automotive diagnostic interface where an MCU must drive and read the ISO 9141 K-line through an MC33290 transceiver, with battery power and ESD protection.
What is in this drawing
Read the decisions behind it.
01
Use MC33290 as the K-line transceiver IC between MCU TX/RX and the K-line bus
02
Add an external diode from K-line to ground for ESD protection and a pull-up to fused battery voltage
03
Power the MCU from a regulated 5V rail derived from the fused 12V vehicle battery
Reuse this netlist for OBD-II K-line interfaces, vehicle diagnostics, and ISO 9141 transceiver designs needing ESD robustness.
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