MPC2105A

•MPC2106A•MPC2105B•MPC2106B

1

MOTOROLA FAST SRAM

512KB and 1MB BurstRAM

™

Secondary Cache Modules for

PowerPC

™ PReP/CHRP Platforms

The MPC2105A/B and the MPC2106A/B are designed to provide burstable, high

performance L2 cache for the PowerPC 60x microprocessor family in conformance

with the PowerPC Reference Platform (PReP) and the PowerPC Common Hardware

Reference Platform (CHRP) specifications.

The MPC2105A/B and MPC2106A/B utilize synchronous BurstRAMs. The

modules are configured as 64K x 72, and 128K x 72 bits in a 178 (89 x 2) pin DIMM

format. The MPC2105A/B uses four of the 3 V 64K x 18; the MPC2106A/B uses eight

of the 3 V 64K x 18. For tag bits, a 5 V cache tag RAM configured as 16K x 12 for tag

field plus 16K x 2 for valid and dirty status bits is used.

Bursts can be initiated with the ADS signal. Subsequent burst addresses are

generated internal to the BurstRAM by the CNTEN signal.

Write cycles are internally self timed and are initiated by the rising edge of the clock

(CLKx) inputs. Eight write enables are provided for byte write control.

Presence detect pins are available for auto configuration of the cache control.

The module family pinout will support 5 V and 3.3 V components for a clear path

to lower voltage and power savings. Both power supplies must be connected.

All of these cache modules are plug and pin compatible with each other.

• PowerPC–style Burst Counter on Chip

• Flow–Through Data I/O

• Plug and Pin Compatibility

• Multiple Clock Pins for Reduced Loading

• 20 Ω Series Resistors on DL and DH Pins for Noise

Reduction (MPC2105A/6A)

• All Cache Data and Tag I/Os are LVTTL (3.3 V) Compatible

• Three State Outputs

• Byte Write Capability

• Fast Module Clock Rates: Up to 66 MHz

• Fast SRAM Access Times: 10 ns for Tag RAM Match

9 ns for Data RAM

• Decoupling Capacitors for Each Fast Static RAM

• High Quality Multi–Layer FR4 PWB With Separate Power and Ground Planes

• 178 Pin Card Edge Module

• Burndy Connector, Part Number: ELF178KSC–3Z50

BurstRAM is a trademark of Motorola.

The PowerPC name is a trademark of IBM Corp., used under license therefrom.

Order this document

by MPC2105A/D

MOTOROLA

SEMICONDUCTOR TECHNICAL DATA

MPC2105A

MPC2106A

MPC2105B

MPC2106B

178–LEAD CARD EDGE

TOP VIEW

MPC2105A/B CASE 1132A–01

MPC2106A/B CASE 1132–01

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12/19/96