P4C174
HIGH SPEED 8K x 8
CACHE TAG STATIC RAM
FEATURES
P4C174
High Speed Address-To-Match - 8 ns Maximum
Access Time
High-Speed Read-Access Time
– 8/10/12/15/20/25 ns (Commercial)
Open Drain MATCH Output
Reset Function
8-Bit Tag Comparison Logic
Automatic Powerdown During Long Cycles
DESCRIPTION
The P4C174 is a 65,536 bit high speed cache tag static
RAM organized as 8K x 8. The CMOS memory has equal
access and cycle times. Inputs are fully TTL-compatible.
The cache tag RAMs operate from a single 5V±10%
power supply. An 8-bit data comparator with a MATCH
output is included for use as an address tag comparator in
high speed cache applications. The reset function provides the capability to reset all memory locations to a LOW
level.
The MATCH output of the P4C174 reflects the comparison result between the 8-bit data on the I/O pins and
Data Retention at 2V for Battery Backup Operation
Advanced CMOS Technology
Low Power Operation
— Active: 750 mW Typical at 25 ns
— Standby: 500 µW Typical
Package Styles Available
— 28 Pin 300 mil Plastic DIP
— 28 Pin 300 mil Plastic SOJ
Single Power Supply
— 5V±10%
the addressed memory location. 8K Cache lines can be
mapped into 1M-Byte address spaces by comparing 20
address bits organized as 13-line address bits and 7-page
address bits.
Low power operation of the P4C174 is enhanced by
automatic powerdown when the memory is deselected or
during long cycle times. Also, data retention is maintained
down to V
= 2.0. Typical battery backup applications
CC
consume only 30 µW at VCC = 3.0V.
FUNCTIONAL BLOCK DIAGRAM
WE
OE
CE
ADDRESS
DATA
I/O
ROW
RESET
8
COMPARATOR
8
ROW
SELECT
8
1 (IF MATCH)
8
8
256 x 32 x 8
MEMORY
ARRAY
COLUMN SELECT
& COLUMN
SENSE
COLUMN
ADDRESS
MATCH (OPEN DRAIN)
PIN CONFIGURATION
RESET
1
A
2
12
A
7
3
A
4
6
A
5
5
A
6
4
A
3
7
A
8
2
A
1
I/0
I/0
I/0
GND
9
A
10
0
11
0
12
1
2
13
14
5
8
DIP (P5), SOJ (J5)
TOP VIEW
174.1
Means Quality, Service and Speed
99
V
28
cc
27
WE
26
MATCH
25
A
8
24
A
9
23
A
11
22
OE
21
A
10
20
CE
19
I/0
7
18
I/0
6
17
I/0
5
16
I/0
4
15
I/0
3
1Q97
P4C174
MAXIMUM RATINGS
(1)
Symbol Parameter Value Unit
V
CC
Power Supply Pin with –0.5 to +7 V
Respect to GND
Terminal Voltage with –0.5 to
V
TERM
Respect to GND VCC +0.5 V
(up to 7.0V)
T
A
Operating Temperature –55 to +125 °C
RECOMMENDED OPERATING
TEMPERATURE AND SUPPLY VOLTAGE
Grade(2)
Commercial
Ambient
Temperature
0°C to +70°C
GND
0V 5.0V ± 10%
V
CC
DC ELECTRICAL CHARACTERISTICS
Over recommended operating temperature and supply voltage
Symbol
V
IH
V
IL
V
HC
V
LC
V
CD
V
OL
Input High Voltage
Input Low Voltage
CMOS Input High Voltage
CMOS Input Low Voltage
Input Clamp Diode Voltage
Output Low Voltage
(TTL Load)
V
OH
Output High Voltage
(TTL Load)
I
LI
I
LO
I
SB
Input Leakage Current
Output Leakage Current
Standby Power Supply
Current (TTL Input Levels)
I
SB1
Standby Power Supply
Current
(CMOS Input Levels)
n/a = Not Applicable
Notes:
1. Stresses greater than those listed under MAXIMUM RATINGS may
cause permanent damage to the device. This is a stress rating only
and functional operation of the device at these or any other conditions
above those indicated in the operational sections of this specification
is not implied. Exposure to MAXIMUM rating conditions for extended
periods may affect reliability.
Parameter
Test Conditions
VCC = Min., IIN = 18 mA
IOL = +8 mA, VCC = Min.
IOH = –4 mA, VCC = Min.
VCC = Max.
VIN = GND to V
CC
VCC = Max., CE = VIH,
V
= GND to V
OUT
CE ≥ V
V
= Max .,
CC
IH
CC
f = Max., Outputs Open
CE ≥ V
V
= Max.,
CC
HC
f = 0, Outputs Open
VIN ≤ VLC or VIN ≥ V
HC
Symbol Parameter Value Unit
T
BIAS
Temperature Under –55 to +125 °C
Bias
T
STG
P
T
I
OUT
CAPACITANCES
Storage Temperature –65 to +150 °C
Power Dissipation 1.0 W
DC Output Current 50 mA
(4)
VCC = 5.0V, TA = 25°C, f = 1.0MHz
Symbol
C
IN
C
OUT
(2)
2. Extended temperature operation guaranteed with 400 linear feet per
minute of air flow.
3. Transient inputs with VIL and IIL not more negative than –3.0V and
–100mA, respectively, are permissible for pulse widths up to 20 ns.
4. This parameter is sampled and not 100% tested.
Parameter
Input Capacitance
Output Capacitance
P4C174
Min
2.2
–0.5
VCC –0.2
–0.5
(3)
(3)
Max
VCC +0.5
0.8
VCC +0.5
0.2
–1.2
0.4
2.4
–5
–5
___
___
+5
+5
25
5
Conditions
VIN = 0V
V
= 0V
OUT
Unit
V
V
V
V
V
V
V
µA
µA
mA
mA
Typ.
5
7
Unit
pF
pF
100
POWER DISSIPATION CHARACTERISTICS VS. SPEED
P4C174
Symbol Parameter
I
CC
Dynamic Operating Current* Commercial
Temperature
Range
–8 –10 –12 –15 –20 –25
200 180 170 160 155 150
*VCC = 5.5V. Tested with outputs open. f = Max. Switching inputs are 0V and 3V. CE = VIL, OE = VIH.
DATA RETENTION CHARACTERISTICS (P4C174 Military Temperature Only)
Typ.*
Symbol
V
I
CCDR
t
CDR
DR
VCC for Data Retention
Data Retention Current
Chip Deselect to
Data Retention Time
†
t
R
*TA = +25˙C
§tRC = Read Cycle Time
†
This parameter is guaranteed but not tested.
Operation Recovery Time
Parameter
Test Conditons
CE ≥ VCC –0.2V,
VIN ≥ VCC –0.2V
or VIN ≤ 0.2V
Min
2.0
0
t
RC
2.0V 3.0V
10
§
VCC =
2.0V 3.0V
15 600 900
Max
VCC =
Unit
mA
Unit
V
µA
ns
ns
READ CYCLE NO. 1 (
ADDRESS
OE
CE
DATA OUT
OEOE
OE CONTROLLED)
OEOE
t
AA
t
OE
(1)
t
OLZ
t
AC
(1)
t
LZ
(2,3)
(4)
t
RC
t
OH
(1)
t
OHZ
(1)
t
HZ
101
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