AMD-K6 Datasheet, PDF (247/346 Pages) Advanced Micro Devices – AMD-K6 Processor

20695H/0—March 1998
Preliminary Information
AMD-K6^® Processor Data Sheet
13 Power and Grounding
13.1
Power Connections
The AMD-K6 processor is a dual voltage device. Two separate
supply voltages are required: V_CC2 and V_CC3. V_CC2 provides the
core voltage for the processor and V_CC3 provides the I/O voltage.
See “Electrical Data” on page 233 for the value and range of V_CC2
and V_CC3.
There are 28 V_CC2, 32 V_CC3, and 68 V_SS pins on the AMD-K6
processor. (See “Pin Designations” on page 269 for all power
and ground pin designations.) The large number of power and
ground pins are provided to ensure that the processor and
package maintain a clean and stable power distribution
network.
For proper operation and functionality, all V_CC2, V_CC3, and V_SS
pins must be connected to the appropriate planes in the circuit
board. The power planes have been arranged in a pattern to
simplify routing and minimize crosstalk on the circuit board.
The isolation region between two voltage planes must be at
least 0.254mm if they are in the same layer of the circuit board.
(See Figure 79 on page 230.) In order to maintain a
low-impedance current sink and reference, the ground plane
must never be split.
Although the AMD-K6 has two separate supply voltages, there
are no special power sequencing requirements. The best
procedure is to minimize the time between which V_CC2 and V_CC3
are either both on or both off.
Chapter 13
Power and Grounding
229