Other Parts Discussed in Thread: TRS3243, GD75232, CD4010B
Hello,
I have a motherboard that may be connected to an external peripheral, using several signals to communicate between them (UART + controls). The peripheral may draw some power (up to 2A), cable used is a classic ribbon cable (1.27mm pitch), with max distance about 1 m (4 ft), max baudrate 115200bps.
I initially choose a RS232 transceiver to communicate between them (TRS3243 / TRS3238), but I'm looking to replace this "costly" solution by standard logic. I have on both board a power supply rail 10-15V, so the CD40106B may be used. With schmitt trigger inputs and such high VCC voltage, I think I may have a good noise immunity, and also immunity to ground shifts that may occur when peripheral draw high current. Moreover, the EMC emissions may be reduced since there is no charge-pump.
I will add serial resistor on the output of the drivers, and also on the inputs. I have to add extra ESD protection, since CD40106B logics limited to 2KV.
Can I simply add a TVS array that may clamp voltages to 30V during surges ? When a ESD surge comes in, it may be clamped to 30V, but does the 2KV ESD protection enough to absorb it, or have I to add additoinnal current limiting serial resistor and capacitance ?
Do I miss something ?
Thank you
Aurelien