Kontron COMe Starterkit Eval T2 - Manual (Page 145)

COM Express Interfaces
Figure 58: Protecting Logic Level Signals on Pins Reclaimed from VCC_12V
PICMG ® COM Express ® Carrier Board Design Guide Rev. 2.0 / December 6, 2013
145/218
COM Ex
Module Pin
MODULE
3.3V RAIL
COM Ex
Module Pin
3.3V CMOS
LOGIC
3.3V CMOS
LOGIC
COM Ex
Carrier Pin
COM Ex
Carrier Pin
VCC_3.3V or
VCC_3.3V_SBY
2N7002
2N7002
1K
1/4W
0805
4.7K
47K
4.7K
Input logic low level at
this node must be 0.5V
max with this Module
circuit and the chosen
Carrier circuit
Module Inputs Reclaimed from VCC _12V pool
Module Outputs Reclaimed from VCC _12V pool Carrier Inputs Reclaimed from VCC _12V pool
Carrier Outputs Reclaimed from VCC _12V pool
POWER RAIL MAY BE
SUSPEND OR S 0 RAIL,
AS APPROPRIATE