50
COM Express® Carrier Board Design Guide
2.14
General Purpose I2C Bus Interface
2.14.1 Signal Definitions
Table 14:
General Purpose I2C Interface Signal Descriptions
Signal
Pin
Description
I/O
Power Rail
I2C_CK
B33
General Purpose I2C Clock output I/O OD CMOS
3.3V Suspend
I2C_DAT
B34
General Purpose I2C data I/O line. I/O OD CMOS
3.3V Suspend
2.14.2 Reference Schematics
Figure 22: System Configuration EEPROM Circuitry
2.14.3 Connectivity Considerations
The maximum capacitance allowed on the Carrier General Purpose I2C bus lines (I2C_DAT,
I2C_CK) is specified by the module vendor. The carrier designer should ensure that the
maximum capacitance is not exceeded and the rise/fall times of the signals meet the I2C bus
specification. As a rule, an IC input has 8pF of capacitance, and a PCB trace has 3.8pF per inch
of trace length.
Содержание ET976
Страница 1: ...COM EXPRESS CARRIER BOARD DESIGN GUIDE Version 1 0 January 2022...
Страница 10: ...4 COM Express Carrier Board Design Guide 2 1 2 Schematic Examples Figure 2 PCI Express x1 Slot Example...
Страница 11: ...COM Express Carrier Board Design Guide 5 Figure 3 PCI Express x4 Slot Example...
Страница 12: ...6 COM Express Carrier Board Design Guide Figure 4 PCIe Mini Card Reference Circuitry...
Страница 16: ...10 COM Express Carrier Board Design Guide 2 2 1 Reference Schematics Figure 5 x1 x4 x8 x16 Slot...
Страница 18: ...12 COM Express Carrier Board Design Guide 2 3 1 1 Reference Schematic Figure 6 DisplayPort Reference Schematics...
Страница 19: ...COM Express Carrier Board Design Guide 13 Figure 7 HDMI Example 1...
Страница 20: ...14 COM Express Carrier Board Design Guide Figure 7 HDMI Example 2...
Страница 21: ...COM Express Carrier Board Design Guide 15 Figure 8 DVI Example 1...
Страница 22: ...16 COM Express Carrier Board Design Guide Figure 8 DVI Example 2...
Страница 30: ...24 COM Express Carrier Board Design Guide 2 6 2 Reference Schematics Figure 12 USB 3 0 Example 1...
Страница 31: ...COM Express Carrier Board Design Guide 25 Figure 12 USB 3 0 Example 2...
Страница 36: ...30 COM Express Carrier Board Design Guide 2 8 2 Reference Schematics Figure 14 LVDS Reference Schematic 1...
Страница 37: ...COM Express Carrier Board Design Guide 31 Figure 14 LVDS Reference Schematic 2...
Страница 40: ...34 COM Express Carrier Board Design Guide 2 9 2 Reference Schematics Figure 15 eDP Reference Schematic...
Страница 43: ...COM Express Carrier Board Design Guide 37 2 10 2 VGA Reference Schematics Figure 16 VGA Reference Schematics 1...
Страница 44: ...38 COM Express Carrier Board Design Guide Figure 16 VGA Reference Schematics 2...
Страница 48: ...42 COM Express Carrier Board Design Guide Figure 18 HDA Example Schematic 2...
Страница 52: ...46 COM Express Carrier Board Design Guide Figure 19 LPC Super I O Example 2...
Страница 61: ...COM Express Carrier Board Design Guide 55 Figure 24 General Purpose Serial Port Example 2...
Страница 63: ...COM Express Carrier Board Design Guide 57 2 17 2 Reference Schematics Figure 25 CAN Bus Example 1...
Страница 66: ...60 COM Express Carrier Board Design Guide 2 18 1 Speaker Output Figure 26 Speaker Output Circuitry...
Страница 70: ...64 COM Express Carrier Board Design Guide Figure 28 PWRBTN and SYS_RESET Circuitry...
Страница 72: ...66 COM Express Carrier Board Design Guide 2 18 6 Fan Connector Figure 31 Fan Connector Reference Schematic...
Страница 84: ...78 COM Express Carrier Board Design Guide Chapter 4 Carrier Board PCB Layout Guidelines...
Страница 88: ...82 COM Express Carrier Board Design Guide 4 3 Trace Impedance Considerations Figure 39 Stackup Impedance...