1
April 20, 2004
U6264B
Standard 8K x 8 SRAM
The U6264B is a static RAM manu-
factured using a CMOS process
technology with the following ope-
rating modes:
- Read - Standby
- Write - Data Retention
The memory array is based on a
6-transistor cell.
The circuit is activated by the rising
edge of E2 (at E1 = L), or the falling
edge of E1 (at E2 = H). The
address and control inputs open
simultaneously. According to the
information of W and G, the data
inputs, or outputs, are active. In a
Read cycle, the data outputs are
activated by the falling edge of G,
afterwards the data word read will
be available at the outputs DQ0 -
DQ7. After the address change, the
data outputs go High-Z until the
new read information is available.
The data outputs have no preferred
state. If the memory is driven by
CMOS levels in the active state,
and if there is no change of the
address, data input and control
signals W or G, the operating cur-
rent (at IO = 0 mA) drops to the
value of the operating current in the
Standby mode. The Read cycle is
finished by the falling edge of E2 or
W, or by the rising edge of E1,
respectively.
Data retention is guaranteed down
to 2 V. With the exception of E2, all
inputs consist of NOR gates, so
that no pull-up/pull-down resistors
are required. This gate circuit
allows to achieve low power
standby requirements by activation
with TTL-levels too.
If the circuit is inactivated by
E2 = L, the standby current (TTL)
drops to 150 µA typ.
!8192 x 8 bit static CMOS RAM
!70 ns Access Times
!Common data inputs and
outputs
!Three-state outputs
!Typ. operating supply current
70 ns: 10 mA
!Standby current:
< 2 µA at Ta 70 °C
!Data retention current at 2 V:
< 1 µA at Ta 70 °C
!TTL/CMOS-compatible
!Automatic reduction of power
dissipation in long Read or Write
cycles
!Power supply voltage 5 V
!Operating temperature ranges:
0 to 70 °C
-40 to 85 °C
-40 to 125 °C
!QS 9000 Quality Standard
!ESD protection > 2000 V
(MIL STD 883C M3015.7)
!Latch-up immunity > 100 mA
!Packages: PDIP28 (600 mil)
SOP28 (330 mil)
Pin Description
Signal Name Signal Description
A0 - A12 Address Inputs
DQ0 - DQ7 Data In/Out
E1 Chip Enable 1
E2 Chip Enable 2
GOutput Enable
WWrite Enable
VCC Power Supply Voltage
VSS Ground
n.c. not connected
Pin Configuration
1
n.c. VCC
28
2
A12 W (WE)
27
4
A6 A8
25
5
A5 A9
24
3
A7 E2 (CE2)
26
6
A4 A11
23
7
A3 G (OE)
22
8
A2 A10
21
12
DQ1 DQ5
17
9
A1 E1 (CE1)
20
10
A0 DQ7
19
11
DQ0 DQ6
18
13
DQ2 DQ4
16
14
VSS DQ3
15
PDIP
Top View
SOP
Features Description
2 April 20, 2004
U6264B
Block Diagram
*H or L
Operating Mode E1 E2 W GDQ0 - DQ7
Standby/not selected
* L * * High-Z
H*** High-Z
Internal Read L H H H High-Z
Read L H H L Data Outputs Low-Z
Write L H L * Data Inputs High-Z
Truth Table
Address
Change
Detector
A0
A1
A2
A3
A10
Memory Cell
Array
256 Rows x
256 Columns
Row Decoder
Row Address
Inputs
Column Decoder
Common Data I/O
Sense Amplifier/
Write Control Logic
Clock
Generator
1
DQ0
DQ1
DQ2
DQ3
DQ4
DQ5
DQ6
DQ7
E2
E1
Column Address
Inputs
VCC VSS W G
A4
A5
A6
A7
A8
A9
A11
A12
3
April 20, 2004
U6264B
aStresses greater than those listed under „Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating
only, and functional operation of the device at condition above those indicated in the operational sections of this specification is not implied.
Exposure to absolute maximum rating conditions for extended periods may affect reliability
bMaximum voltage is 7 V
cNot more than 1 output should be shorted at the same time. Duration of the short circuit should not exceed 30 s.
Absolute Maximum Ratings aSymbol Min. Max. Unit
Power Supply Voltage VCC -0.3 7 V
Input Voltage VI-0.3 VCC + 0.5 bV
Output Voltage VO-0.3 VCC + 0.5 bV
Power Dissipation PD-1W
Operating Temperature C-Type
K-Type
A-Type
Ta0
-40
-40
70
85
125
°C
°C
°C
Storage Temperature C/K-Type
A-Type
Tstg -55
-65
125
150
°C
°C
Output Short-Circuit Current
at VCC = 5 V and VO = 0 V c| IOS |100mA
Characteristics
All voltages are referenced to VSS = 0 V (ground).
All characteristics are valid in the power supply voltage range and in the operating temperature range specified.
Dynamic measurements are based on a rise and fall time of 5 ns, measured between 10 % and 90 % of VI,as well as
input levels of VIL = 0 V and VIH = 3 V. The timing reference level of all input and output signals is 1.5 V,
with the exception of the tdis-times, in which cases transition is measured ± 200 mV from steady-state voltage.
d-2 V at Pulse Width 10 ns
Recommended
Operating Conditions Symbol Conditions Min. Max. Unit
Power Supply Voltage VCC 4.5 5.5 V
Data Retention Voltage VCC(DR) 2.0 V
Input Low Voltage dVIL -0.3 0.8 V
Input High Voltage VIH 2.2 VCC + 0.3 V
4 April 20, 2004
U6264B
Electrical Characteristics Symbol Conditions Min. Max. Unit
Supply Current - Operating Mode ICC(OP) VCC
VIL
VIH
tcW
= 5.5 V
= 0.8 V
= 2.2 V
= 70 ns
55 mA
Supply Current - Standby Mode
(CMOS level)
ICC(SB) VCC
VE1 = VE2
or VE2
C-Type
K-Type
A-Type
= 5.5 V
= VCC - 0.2 V
= 0.2 V
2
5
100
µA
µA
µA
Supply Current - Standby Mode
(TTL level)
ICC(SB)1 VCC
VE1 = VE2
or VE2
= 5.5 V
= 2.2 V
= 0.8 V
3mA
Supply Current - Data Retention
Mode
ICC(DR) VCC(DR)
VE1 = VE2
or VE2
C-Type
K-Type
A-Type
= 2 V
= VCC(DR) - 0.2 V
= 0.2 V
1
3
50
µA
µA
µA
Output High Voltage
Output Low Voltage
VOH
VOL
VCC
IOH
VCC
IOL
= 4.5 V
= -1.0 mA
= 4.5 V
= 3.2 mA
2.4
0.4
V
V
Output High Current
Output Low Current
IOH
IOL
VCC
VOH
VCC
VOL
= 4.5 V
= 2.4 V
= 4.5 V
= 0.4 V
3.2
-1 mA
mA
Input Leakage Current
High
Low
IIH
IIL
VCC
VIH
C/K-Type
A-Type
VCC
VIL
C/K-Type
A-Type
= 5.5 V
= 5.5 V
= 5.5 V
= 0 V
-
-
-1
-2
1
2
-
-
µA
µA
µA
µA
Output Leakage Current
High at Three-State Outputs
Low at Three-State Outputs
IOHZ
IOLZ
VCC
VOH
C/K-Type
A-Type
VCC
VOL
C/K-Type
A-Type
= 5.5 V
= 5.5 V
= 5.5 V
= 0 V
-
-
-1
-2
1
2
-
-
µA
µA
µA
µA
5
April 20, 2004
U6264B
Switching Characteristics
Symbol
Min. Max. Unit
Alt. IEC
Time to Output in Low-Z tLZ tt(QX) 510ns
Cycle Time
Write Cycle Time
Read Cycle Time
tWC
tRC
tcW
tcR
70
70
ns
ns
Access Time
E1 LOW or E2 HIGH to Data Valid
G LOW to Data Valid
Address to Data Valid
tACE
tOE
tAA
ta(E)
ta(G)
ta(A)
-
-
-
70
40
70
ns
ns
ns
Pulse Widths
Write Pulse Width
Chip Enable to End of Write
tWP
tCW
tw(W)
tw(E)
50
65
ns
ns
Setup Times
Address Setup Time
Chip Enable to End of Write
Write Pulse Width
Data Setup Time
tAS
tCW
tWP
tDS
tsu(A)
tsu(E)
tsu(W)
tsu(D)
0
65
50
35
ns
ns
ns
ns
Data Hold Time
Address Hold from End of Write
tDH
tAH
th(D)
th(A)
0
0
ns
ns
Output Hold Time from Address Change tOH tv(A) 5ns
E1 HIGH or E2 LOW to Output in High-Z
W LOW to Output in High-Z
G HIGH to Output in High-Z
tHZCE
tHZWE
tHZOE
tdis(E)
tdis(W)
tdis(G)
0
0
0
25
30
25
ns
ns
ns
Data Retention Mode E1-Controlled
Data Retention
4.5 V
tDR trec
VCC
E1
VCC(DR) 2 V
VE2(DR) VCC(DR) - 0.2 V or VE2(DR) 0.2 V
VCC(DR) - 0.2 V VE1(DR) VCC(DR) + 0.3 V
0 V
2.2 V
2.2 V
VCC(DR) 2 V
Data Retention Mode E2-Controlled
Data Retention trec
tDR
0.8 V
0.8 V VE2(DR) 0.2 V
4.5 V
0 V
VCC
E2
Chip Deselect to Data Retention Time tDR : min 0 ns
Operating Recovery Time trec : min tcR
6 April 20, 2004
U6264B
Test Configuration for Functional Check
VIH
VIL
VSS
VCC
5 V
960
510
30 pFe
VO
Simultaneous measure-
ment of all 8 output pins
Input level according to the
relevant test measurement
e In measurement of tdis(E), tdis(W), tdis(G) the capacitance is 5 pF.
All pins not under test must be connected with ground by capacitors.
A0
A1
A2
A3
A4
A5
A6
A7
A8
A9
A10
A11
A12
E1
E2
W
G
DQ0
DQ1
DQ2
DQ3
DQ4
DQ5
DQ6
DQ7
Capacitance Conditions Symbol Min. Max. Unit
Input Capacitance VCC = 5.0 V
VI = VSS
CI8pF
Output Capacitance f = 1 MHz
Ta = 25 °CCO10 pF
Date of manufacture
(The first 2 digits indicating
the year, and the last 2
digits the calendar week.)
Leadfree Green Package
Product specification
Assembly location and
trace code
Internal Code
Ordering Code
Device Marking (example)
ZMD
U6264BS2K
07LL C 0425
1 ZZ G1
Access Time
07 = 70 ns
LLS2 07KU6264B
Typ e
Package
D = PDIP28 (600 mil, only C/K-Type)
S = SOP28 (330 mil) Type 1
S2 = SOP28 (330 mil) Type 2
Operating Temperature Range
C = 0 to 70 °C
K = -40 to 85 °C
A = -40 to 125 °C
Leadfree Option
blank = Standard Package
G1 = Leadfree Green Package f
Power Consumption
blank = Standard (only A-Type)
LL = Very Low Power (C/K-Type)
f on special request
Example
7
April 20, 2004
U6264B
th(D)
Read Cycle 1 (during Read cycle: E1 = G = VIL, E2 = W = VIH)
Read Cycle 2 (during Read cycle: W = VIH)
Write Cycle 1 (W-controlled)
ta(A)
Previous Data Valid Output Data Valid
tcR
Addresses Valid
tv(A)
Ai
DQi
Ai
E1
E2
G
DQi
Output
Output
tdis(E)
tcR
tsu(A) ta(E)
tsu(A)
tt(QX)
tt(QX)
tt(QX)
ta(G)
ta(E) tdis(E)
tdis(G)
Addresses Valid
Output Data Valid
Ai
E1
E2
W
DQi
Input
G
DQi
Output
tcW
tsu(E) th(A)
tw(W)
tsu(A)
tsu(E)
tsu(D)
tdis(W) tt(QX)
Addresses Valid
Input Data Valid
High-Z
High-Z
8 April 20, 2004
U6264B
High-Z
tsu(A)
Input Data Valid
th(D)
tsu(W)
tw(E)
tsu(D)
tcW
Addresses Valid
tsu(E) th(A)
tt(QX) tdis(W)
Ai
E1
E2
W
DQi
Input
G
DQi
Output
tsu(A)
undefined L- or H-level
Write Cycle 2 (E1-controlled)
Write Cycle 3 (E2-controlled)
th(D)
Ai
E1
E2
W
DQi
Input
G
DQi
Output
tcW
tw(E) th(A)
tsu(W)
tsu(E)
tsu(D)
tdis(W)
tt(QX)
Addresses Valid
Input Data Valid
High-Z
The information describes the type of component and shall not be considered as assured characteristic. Terms of
delivery and rights to change design reserved.
Zentrum Mikroelektronik Dresden AG
Grenzstraße 28 D-01109 Dresden P. O. B. 80 01 34 D-01101 Dresden Germany
Phone: +49 351 8822 306 Fax: +49 351 8822 337 Email: memory@zmd.de http://www.zmd.de
April 20, 2004
U6264B
LIFE SUPPORT POLICY
ZMD 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 ZMD product could create a situation where personal injury or death may occur.
Components used in life-support devices or systems must be expressly authorized by ZMD for such purpose.
LIMITED WARRANTY
The information in this document has been carefully checked and is believed to be reliable. However Zentrum
Mikroelektronik Dresden AG (ZMD) makes no guarantee or warranty concerning the accuracy of said information
and shall not be responsible for any loss or damage of whatever nature resulting from the use of, or reliance upon it.
The information in this document describes the type of component and shall not be considered as assured charac-
teristics.
ZMD does not guarantee that the use of any information contained herein will not infringe upon the patent, trade-
mark, copyright, mask work right or other rights of third parties, and no patent or licence is implied hereby. This
document does not in any way extent ZMD’s warranty on any product beyond that set forth in its standard terms and
conditions of sale.
ZMD reserves terms of delivery and reserves the right to make changes in the products or specifications, or both,
presented in this publication at any time and without notice.