K6R4008V1B-C/B-L, K6R4008V1B-I/B-P

CMOS SRAM

PRELIMINARY

Rev 2.2

- 8 -

May 1999

NOTES(WRITE CYCLE)

1. All write cycle timing is referenced from the last valid address to the first transition address.

2. A write occurs during the overlap of a low CS and WE. A write begins at the latest transition CS going low and WE going low ;

write.

6. If OE, CS and WE are in the Read Mode during this period, the I/O pins are in the output low-Z state. Inputs of opposite phase

of the output must not be applied because bus contention can occur.

7. For common I/O applications, minimization or elimination of bus contention conditions is necessary during read and write cycle.

8. If CS goes low simultaneously with WE going or after WE going low, the outputs remain high impedance state.

9. Dout is the read data of the new address.

10. When CS is low : I/O pins are in the output state. The input signals in the opposite phase leading to the output should not be

applied.

FUNCTIONAL DESCRIPTION

* X means Don

CS

WE

OE

Mode

I/O Pin

Supply Current

H

X

X*

Not Select

High-Z

L

H

H

Output Disable

High-Z

L

H

L

Read

L

L

X

Write

°C)

* The above parameters are also guaranteed at industrial temperature range.

Data Retention Characteristic is for L-ver only.

Parameter

Symbol

Test Condition

Min.

Typ.

Max.

Unit

CS

2.0

-

3.6

V

Data Retention Current

-

-

1.0

mA

-

-

0.7

mA

Data Retention Set-Up Time

See Data Retention

Wave form(below)

0

-

-

ns

Recovery Time

5

-

-

ms

DATA RETENTION WAVE FORM

3.0V

CS

GND

Data Retention Mode

CS

CS controlled