MOTOROLA
SEMICONDUCTOR TECHNICAL DATA
Order this document
by MCM67T415/D
Advance Information
MCM67T415
16K x 15 Bit Cache Tag RAM
for Pentium™ Processors
The MCM67T415 is a 245,760 bit cache–tag static RAM designed to support
Pentium microprocessors at bus speeds up to 66 MHz. It is organized as 16K words
of 15 bits each and is fabricated using Motorola‘s high performance, silicon gate
BiCMOS technology. There are twelve common I/O tag bits and three separate I/O
status bits. A 12–bit comparator is on–chip to allow fast comparison of the 12 stored
tag bits with the current tag input data. An active high MATCH output is generated
when the valid bit is true and these two groups of data are the same for a given
address.
This high–speed MATCH signal, with tAVMV times as fast as 9 ns, provides the
fastest possible enabling of secondary cache accesses.
The three separate I/O status bits (VALID, DIRTY, and WT) can be configured for
either dedicated or generic functionality, depending on the SFUNC input pin. With
SFUNC low, the status bits are defined and used internally by the device, allowing
easier determination of the validity and use of the given tag data. SFUNC high
releases the defined internal status bit usage and control, allowing users to
configure the status bit information to fit their system needs. A synchronous RESET
pin, when held low at a rising clock edge, will reset all status bits in the array for easy
invalidation of all tag addresses.
The MCM67T415 also provides the option for burst ready (BRDY) generation
within the cache tag itself, based upon MATCH, VALID bit, WT bit, and other external
inputs provided by the user. This can significantly simplify cache controller logic and
minimize cache decision time. Match and read operations are both asynchronous
in order to provide the fastest access times possible, while write operations are
synchronous for ease of system timing.
The MCM67T415 uses a 5 V power supply on VCC and VSS, with separate VCCQ
pins provided for the outputs to offer compliance with both 5 V TTL and 3.3 V LVTTL
logic levels. The PWRDN pin offers a low–power standby mode, which provides
significant system power savings.
The MCM67T415 is offered in a space saving 80–pin thin quad flat pack (TQFP)
package.
•
16K x 15 Configuration:
– 12 Tag Bits
– Three Status Bits (Valid, Dirty, and WT)
•
Valid Bit used to Qualify Match Output
•
High–Speed Address–to–Match Comparison Times – 9/10/12 ns
•
BRDY Circuitry Included Inside the Cache–Tag for the Highest Speed
Operation
•
Asynchronous Read/Match Operation and Synchronous Write and Reset
Operation
•
Separate Write Enable for Tag Bits and Status Bits
•
Separate Output Enable for Tag Bits, Status Bits, and BRDY
•
Synchronous RESET Pin for Invalidation of all Tag Entries
•
Dual Chip Selects for Easy Depth Expansion with No Performance
Degradation
•
I/O Pins Both 5 V TTL and 3.3 V LVTTL Compatible with VCCQ Pins
•
PWRDN Pin to Place Device in Low–Power Mode
•
Drop–In Replacement for IDT71215
•
Packaged in an 80–Pin Thin Quad Flat Pack (TQFP)
Pentium is a trademark of Intel Corp.
This document contains information on a new product. Motorola reserves the right to change or discontinue this product without notice.
9/10/96
TQ PACKAGE
TQFP
CASE 917A–02
©
Motorola, Inc. 1996
MOTOROLA FAST SRAM
MCM67T415
1
PIN ASSIGNMENTS
VALIDD
VCC
VSS
PWRDN
E2
E1
WT
WS
VCC
VSS
RESET
K
GS
GT
BRDYG
TDQ11
VSS
TDQ10
VCCQ
TDQ9
VSS
VSS
VSS
VSS
DIRTYD
WTD
A0
A1
A2
VCC
VSS
A3
A4
A5
A6
A7
VSS
VSS
VSS
VSS
80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 64 63 62 61
1
60
2
59
58
3
4
57
5
56
6
55
7
54
8
53
9
52
10
51
11
50
12
49
13
48
14
47
15
46
16
45
17
44
18
43
19
42
20
41
21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40
W/R
BRDYH
BRDYD
A9
A10
A11
A12
A13
DIRTYQ
TDQ0
VSS
TDQ1
VCCQ
TDQ2
TDQ3
A8
SFUNC
VSS
VSS
VCC
VSS
VSS
VSS
TDQ8
TDQ7
TDQ6
VALIDQ
VCCQ
VSS
BRDY
MATCH
VSS
VCCQ
WTQ
TDQ5
TDQ4
NC
VSS
VSS
VSS
Motorola reserves the right to make changes without further notice to any products herein. Motorola makes no warranty, representation or guarantee regarding
the suitability of its products for any particular purpose, nor does Motorola assume any liability arising out of the application or use of any product or circuit, and
specifically disclaims any and all liability, including without limitation consequential or incidental damages. “Typical” parameters which may be provided in Motorola
data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals”
must be validated for each customer application by customer’s technical experts. Motorola does not convey any license under its patent rights nor the rights of
others. Motorola products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other
applications intended to support or sustain life, or for any other application in which the failure of the Motorola product could create a situation where personal injury
or death may occur. Should Buyer purchase or use Motorola products for any such unintended or unauthorized application, Buyer shall indemnify and hold Motorola
and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees
arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that
Motorola was negligent regarding the design or manufacture of the part. Motorola and
are registered trademarks of Motorola, Inc. Motorola, Inc. is an Equal
Opportunity/Affirmative Action Employer.
How to reach us:
USA / EUROPE / Locations Not Listed:
Motorola Literature Distribution;
P.O. Box 20912; Phoenix, Arizona 85036. 1–800–441–2447 or 602–303–5454
MFAX:
RMFAX0@email.sps.mot.com – TOUCHTONE 602–244–6609
INTERNET:
http://Design–NET.com
JAPAN:
Nippon Motorola Ltd.; Tatsumi–SPD–JLDC, 6F Seibu–Butsuryu–Center,
3–14–2 Tatsumi Koto–Ku, Tokyo 135, Japan. 03–81–3521–8315
ASIA/PACIFIC:
Motorola Semiconductors H.K. Ltd.; 8B Tai Ping Industrial Park,
51 Ting Kok Road, Tai Po, N.T., Hong Kong. 852–26629298
MOTOROLA FAST SRAM
◊
*MCM67T415/D*
MCM67T415/D
MCM67T415
3
Talking
京公网安备 11010802033920号
EEWORLD
