am79c974 Advanced Micro Devices, am79c974 Datasheet - Page 25

• Manufacturer Part Number: am79c974
• Description: Pcnettm-scsi Combination Ethernet And Scsi Controller For Pci Systems
• Manufacturer: Advanced Micro Devices

Miscellaneous
RESERVED
Reserved_DO NOT CONNECT
Input
This pin (#116) is reserved for internal test logic. It
MUST NOT BE CONNECTED to anything for proper
chip operation. It’s use is subject to change in future
products.
Power Supply Pins
Analog Power Supply Pins
AVDD
Analog Power (4 Pins)
Power
There are four analog +5 V supply pins. Special atten-
tion should be paid to the printed circuit board layout to
avoid excessive noise on these lines.
Appendix C and the Technical Manual (PID #18738A)
for details.
AVSS
Analog Ground (2 Pins)
Power
There are two analog ground pins. Special attention
should be paid to the printed circuit board layout to avoid
excessive noise on these lines. Refer to Appendix C and
the Technical Manual (PID #18738A) for details.
Refer to
P R E L I M I N A R Y
Am79C974
Digital Power Supply Pins
VDD/DVDD
Digital Power (5 Pins)
Power
There are 5 power supply pins that are used by the inter-
nal digital circuitry. All VDD pins must be connected to a
+5 V supply.
VDDB/VDDB
I/O Buffer Power (5 Pins)
Power
There are 5 power supply pins that are used by the PCI
bus Input/Output buffer drivers. All VDDB pins must be
connected to a +5 V supply.
VSS/DVSS
Digital Ground (9 Pins)
Ground
There are 9 ground pins that are used by the internal
digital circuitry.
VSSB/VSSBS
I/O Buffer Ground (11 Pins)
Ground
There are 11 ground pins that are used by the PCI bus
Input/Output buffer drivers.
AMD
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