MCM32257B Datasheet, PDF (1/8 Pages) Motorola, Inc – 256K x 32 Bit Fast Static RAM Module

MOTOROLA
SEMICONDUCTOR TECHNICAL DATA
256K x 32 Bit
Fast Static RAM Module
The MCM32257B is an 8M bit static random access memory module orga-
nized as 262,144 words of 32 bits. The module is a 64–lead zig–zag in–line pack-
age (ZIP) of eight MCM6229 fast static RAMs packaged in 28–lead SOJ
packages and mounted on a printed circuit board along with eight decoupling ca-
pacitors.
The MCM6229 is a high–performance CMOS fast static RAM organized as
262,144 words of 4 bits, fabricated using high–performance silicon–gate CMOS
technology. Static design eliminates the need for external clocks or timing
strobes, while CMOS circuitry reduces power consumption and provides for
greater reliability.
The MCM32257B is equipped with output enable (G) and four separate byte
enable (E1 – E4) inputs, allowing for greater system flexibility. The G input, when
high, will force the outputs to high impedance. Ex high will do the same for byte x.
PD0 and PD1 are reserved for density identification. PD0 and PD1 are con-
nected to ground. These pins can be used to identify the density of the memory
module.
• Single 5 V ± 10% Power Supply
• Fast Access Time: 15/20/25 ns
• Three–State Outputs
• Fully TTL Compatible
• JEDEC Standard Pinout
• Power Requirement: 960/880/840 mA Maximum, Active AC
• High Board Density ZIP Package
• Byte Operation: Four Separate Chip Enables, One for Each Byte (Eight Bits)
• High Quality Four–Layer FR4 PWB with Separate Internal Power and
Ground Planes
• Incorporates Motorola’s State–of–the–Art Fast Static RAMs
PIN NAMES
A0 – A17 . . . . . . . . . . . . . . . . . . . . . . . . . . . Address Inputs
W . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Write Enable
G . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Output Enable
E1 – E4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Byte Enables
DQ0 – DQ31 . . . . . . . . . . . . . . . . . . . . . . Data Input/Output
VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . + 5 V Power Supply
VSS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ground
PD0 – PD1 . . . . . . . . . . . . . . . . . . . . . . . . Package Density
For proper operation of the device, VSS must be connected
to ground.
Order this document
by MCM32257B/D
MCM32257B
PIN ASSIGNMENT
TOP VIEW
64 LEAD ZIP — CASE 871–01
PD0 2
DQ0 4
DQ1 6
DQ2 8
DQ3 10
VCC 12
A1 14
A3 16
A5 18
DQ4 20
DQ5 22
DQ6 24
DQ7 26
W 28
A7 30
E1 32
1 VSS
3 PD1
5 DQ8
7 DQ9
9 DQ10
11 DQ11
13 A0
15 A2
17 A4
19 DQ12
21 DQ13
23 DQ14
25 DQ15
27 VSS
29 A6
31 E2
E3 34
A9 36
VSS 38
DQ16 40
DQ17 42
DQ18 44
DQ19 46
A11 48
A13 50
A15 52
A16 54
DQ20 56
DQ21 58
DQ22 60
DQ23 62
VSS 64
33 E4
35 A8
37 G
39 DQ24
41 DQ25
43 DQ26
45 DQ27
47 A10
49 A12
51 A14
53 VCC
55 A17
57 DQ28
59 DQ29
61 DQ30
63 DQ31
5/95
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MCM32257B
6–1