AMD-K6 datasheet(247/346 Pages) AMD

247 / 346 page

Chapter 13

Power and Grounding

229

20695H/0—March 1998

AMD-K6® Processor Data Sheet

Preliminary Information

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 VCC3. VCC2 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 VCC3, and 68 VSS 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, VCC3, and VSS

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 Fi gure 79 o n pa ge 2 30.) In o rder to ma intai n 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 VCC3

are either both on or both off.

AMD-K6 Datasheet(PDF) 247 Page - Advanced Micro Devices