SIMTEK STK10C68-C35, STK10C68-C25, STK10C68-C25I, STK10C68-C20, STK10C68-P45I Datasheet

July 1999 4-1

STK10C68

8K x 8 nvSRAM

QuantumTrap™ CMOS

Nonvolatile Static RAM

FEATURES

• 20ns, 25ns, 35ns and 45ns Access Times

• STORE to EEPROM Initiated by Hardware

• RECALL to SRAM Initiated by Hardware or

Power Restore

• Automatic STORE Timing

• 10mA T ypical I

CC

at 200ns Cycle Time

• Unlimited READ, WRITE and RECALL Cycles

• 1,000,000 STORE Cycles to EEPROM

• 100-Year Data Retention over Full Industrial

Temperature Range

• Commercial and Industrial Temperatures

• 28-Pin DIP and SOIC Packages

DESCRIPTION

The Simtek STK10C68 is a fast static RAM with a nonvol­atile electrically erasable

PROM (EEPROM) element

incorporated in each s tatic memory cell. The

SRAM can

be read and written an un limited number of times, while
independent nonvolatile data resides in

EEPROM. Data

may easily be transferred from th e

SRAM to the EEPROM

(the STORE operation), or from the EEPROM to the SRAM
(the RECALL operation), using the NE pin. Transfers

from the

EEPROM to the SRAM (the RECALL operation)

also take place automatically on restoration of power.

The STK10C68 combines the high performance and ease
of use of a fast

SRAM with nonvolatile data integrity.

The STK10C68 features industry-standard pinout for non­volatile

RAMs. MIL-STD-883 and Standard Military Draw-

ing (

SMD #5962-93056) devices are also available.

BLOCK DIAGRAM

COLUMN I/O

COLUMN DEC

STATIC RAM

ARRAY

128 x 512

ROW DECODER

INPUT BUFFERS

EEPROM ARRAY

128 x 512

STORE/

RECALL

CONTROL

STORE

RECALL

A

11

A

7

A

8

DQ

0

DQ

1

DQ

2

DQ

3

DQ

4

DQ

5

DQ

6

DQ

7

G

E
W

A

6

A

5

A

3

A

2

A0A

1

A

10

A

12

A

9

NE

A

4

PIN NAMES

A0 - A

12

Address Inputs
W Write Enable
DQ0 - DQ

7

Data In/Out
E Chip Enable
G Output Enable
NE Nonvolatile Enable
V

CC

Power (+ 5V)
V

SS

Ground

PIN CONFIGURATIONS

NE

A

12

A

7

A

6

A

5

A

4

A

3

A

2

A

1

A

0

DQ

0

DQ

1

DQ

2

V

SS

V

CC

NC
A

8

A

9

A

11

G

W

1
2
3
4
5
6
7
8
9
10
11
12
13
14

28
27
26
25
24
23
22
21
20
19
18
17
16
15

A

10

E
DQ

7

DQ

6

DQ

5

DQ

4

DQ

3

28 - 300 PDIP
28 - 300 CDIP
28 - 350 SOIC

STK10C68

July 1999 4-2

ABSOLUTE MAXIMUM RATINGS

a

Volt age on Input Relati ve to VSS. . . . . . . . . . –0.6V to (VCC + 0.5V)

Volt age on DQ

0-7

. . . . . . . . . . . . . . . . . . . . . . –0.5V to (VCC + 0.5V)

Temperature under Bias . . . . . . . . . . . . . . . . . . . . . –55°C to 125°C

Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . –65°C to 150°C

Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1W

DC Output Current (1 output at a time, 1s duration). . . . . . . . 15mA

DC CHARACTERISTICS (VCC = 5.0V ± 10%)

b

Note b: The STK10C68-20 requires VCC = 5.0V ± 5% supply to operate at specified speed.
Note c: I

CC

1

and I

CC

3

are dependent on output loading and cycle rate. The specified values are obtained with outputs unloaded.

Note d: I

CC

2

is the average current required for the duration of the STORE cycle (t

STORE

).

Note e: E

≥ VIH will not produce standby current levels until any nonvolatile cycle in progress has timed out.

AC TEST CONDITIONS

CAPACITANCE

f

(TA = 25°C, f = 1.0MHz)

Note f: These parameters are guaranteed but not tested.

SYMBOL PARAMETER

COMMERCIAL INDUSTRIAL

UNITS NOTES

MIN MAX MIN MAX

I

CC

1

c

Average VCC Current 100

90
75
65

N/A

90
75
65

mA
mA
mA
mA

t

AVAV

= 20ns

t

AVAV

= 25ns

t

AVAV

= 35ns

t

AVAV

= 45ns

I

CC

2

d

Average VCC Current during STORE 33mAAll Inputs Don’t Care, VCC = max

I

CC

3

c

Average VCC Current at t

AVAV

= 200ns

5V, 25°C, Typical

10 10 mA

W

≥ (V

CC

– 0.2V)

All Others Cycling, CMOS Leve ls

I

SB

1

e

Average VCC Current
(Standby, Cycling TTL Input Levels)

32
27
23
20

N/A

28
24
21

mA
mA
mA
mA

t

AVAV

= 20ns, E ≥ V

IH

t

AVAV

= 25ns, E ≥ V

IH

t

AVAV

= 35ns, E ≥ V

IH

t

AVAV

= 45ns, E ≥ V

IH

I

SB

2

e

VCC Standby Current
(Standby, Stable CMOS Input Levels )

750 750 µA

E

≥ (VCC – 0.2V)

All Others V

IN

≤ 0.2V or ≥ (VCC – 0.2V)

I

ILK

Input Leakage Current

±1 ±1 µA

V

CC

= max

V

IN

= VSS to V

CC

I

OLK

Off-State Output Leakage Current

±5 ±5 µA

V

CC

= max

V

IN

= V

SS

to VCC, E or G ≥ VIH

V

IH

Input Logic “1” Voltage 2.2 V

CC

+ .5 2.2 VCC + .5 V All Inputs

V

IL

Input Logic “0” Voltage VSS – .5 0.8 VSS – .5 0.8 V All Inputs

V

OH

Output Logic “1” Voltage 2.4 2.4 V I

OUT

= –4mA

V

OL

Output Logic “0” Voltage 0.4 0.4 V I

OUT

= 8mA

T

A

Operating Temperature 0 70 –40 85 °C

Input Pulse Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0V to 3V

Input Rise and Fall Times . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ≤ 5ns

Input and Output Timing Reference Levels. . . . . . . . . . . . . . . 1.5V

Output Load. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .See Figure 1

SYMBOL PARAMETER MAX UNITS CONDITIONS

C

IN

Input Capacitance

8pF

∆V = 0 to 3V

C

OUT

Output Capacitance

7pF

∆V = 0 to 3V

Figure 1: AC Output Loading

480 Ohms

30 pF

255 Ohms

5.0V

INCLUDING

OUTPUT

SCOPE AND
FIXTURE

Note a: Stresses 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 condi­tions 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.

STK10C68

July 1999 4-3

SRAM READ CYCLES #1 & #2 (V

CC

= 5.0V ± 10%)

b

Note g: W must be high during SRAM READ cycles and low during SRAM WRITE cycles. NE must be high during entire cycle.
Note h: I/O state assumes E

, G < VIL, W > VIH , and NE ≥ VIH; device is continuously selected.

Note i: Measured +

200mV from steady state output voltage.

SRAM READ CYCLE #1: Address Controlled

g, h

SRAM READ CYCLE #2: E Controlled

g

NO.

SYMBOLS

PARAMETER

STK10C68-20 STK10C68-25 STK10C68-35 STK10C68-45

UNITS

#1, #2 Alt. MIN MAX MIN MAX MIN MAX MIN MAX

1t

ELQV

t

ACS

Chip Enable Access Time 20 25 35 45 ns

2t

AVAV

g

t

RC

Read Cycle Time 20 25 35 45 ns

3t

AVQV

h

t

AA

Address Access Time 22 25 35 45 ns

4t

GLQV

t

OE

Output Enable to Data Valid 8 10 15 20 ns

5t

AXQX

h

t

OH

Output Hol d after Address Chang e 5 5 5 5 ns

6t

ELQX

t

LZ

Chip Enable to Output Active 5 5 5 5 ns

7t

EHQZ

i

t

HZ

Chip Disable to Output Inactive 7 10 13 15 ns

8t

GLQX

t

OLZ

Output Enable to Output Active 0 0 0 0 ns

9t

GHQZ

i

t

OHZ

Output Disable to Output Inactive 7 10 13 15 ns

10 t

ELICCH

f

t

PA

Chip Enable to Power Active 0 0 0 0 ns

11 t

EHICCL

e, f

t

PS

Chip Disable to Power Standby 25 25 35 45 ns

DATA VALID

5

t

AXQX

3

t

AVQV

DQ (DATA OUT)

ADDRESS

2

t

AVAV

6

t

ELQX

STANDBY

DATA VALID

8

t

GLQX

4

t

GLQV

DQ (DATA OUT)

E

ADDRESS

2

t

AVAV

G

I

CC

ACTIVE

1

t

ELQV

10

t

ELICCH

11

t

EHICCL

7

t

EHQZ

9

t

GHQZ