BSI

BS616UV4016

2

R0201-BS616UV4016

Revision

1.3

Sep.

2005

n PIN DESCRIPTIONS

Name

Function

A0-A17 Address Input

These 18 address inputs select one of the 262,144 x 16-bit words in the RAM

CE Chip Enable 1 Input

CE is active LOW. Chip enable must be active when data read form or write to the

device. If either chip enable is not active, the device is deselected and is in standby

power mode. The IO pins will be in the high impedance state when the device is

deselected.

WE Write Enable Input

The write enable input is active LOW and controls read and write operations. With the

chip selected, when WE is HIGH and OE is LOW, output data will be present on the IO

pins; when WE is LOW, the data present on the IO pins will be written into the selected

memory location.

OE Output Enable Input

The output enable input is active LOW. If the output enable is active while the chip is

selected and the write enable is inactive, data will be present on the IO pins and they

will be enabled. The IO pins will be in the high impendence state when OE is inactive.

LB and UB Data Byte Control Input

Lower byte and upper byte data input/output control pins.

IO0-IO15 Data Input/Output

Ports

16 bi-directional ports are used to read data from or write data into the RAM.

Power Supply

GND

Ground

n TRUTH TABLE

MODE

CE

WE

OE

LB

UB

IO0~IO7

IO8~IO15

H

X

X

X

X

High Z

High Z

Chip De-selected

(Power Down)

X

X

X

H

H

High Z

High Z

L

H

H

L

X

High Z

High Z

Output Disabled

L

H

H

X

L

High Z

High Z

L

L

H

L

High Z

Read

L

H

L

L

H

High Z

L

L

H

L

X

Write

L

L

X

L

H

X