Data Sheet M16048EJ2V0DS

6

µPD23C128040BL, 23C128080BL

Input / Output Pin Functions

Pin name

Input / Output

Function

WORD, /BYTE

Input

The pin for switching WORD mode and BYTE mode.

High level : WORD mode (8M-word by 16-bit)

Low level : BYTE mode (16M-word by 8-bit)

A0 to A22

(Address inputs)

Input

Address input pins.

A0 to A22 are used differently in the WORD mode and the BYTE mode.

WORD mode (8M-word by 16-bit)

A0 to A22 are used as 23 bits address signals.

BYTE mode (16M-word by 8-bit)

A0 to A22 are used as the upper 23 bits of total 24 bits of address signal.

(The least significant bit (A

−1) is combined to O15.)

O0 to O7, O8 to O14

(Data outputs)

Output

Data output pins.

O0 to O7, O8 to O14 are used differently in the WORD mode and the BYTE mode.

WORD mode (8M-word by 16-bit)

The lower 15 bits of 16 bits data outputs to O0 to O14.

(The most significant bit (O15) combined to A

−1.)

BYTE mode (16M-word by 8-bit)

8 bits data outputs to O0 to O7 and also O8 to O14 are high impedance.

O15, A

−1

(Data output 15,

LSB Address input)

Output, Input

O15, A

−1 are used differently in the WORD mode and the BYTE mode.

WORD mode (8M-word by 16-bit)

The most significant output data bus (O15).

BYTE mode (16M-word by 8-bit)

The least significant address bus (A

−1).

/CE

(Chip Enable)

Input

Chip activating signal.

When the OE is active, output states are following.

High level : High-Z

Low level : Data out

/OE or OE or DC

(Output Enable, Don’t Care)

Input

Output enable signal. The active level of OE is mask option. The active level of OE

can be selected from high active, low active and Don’t care at order.

−

Supply voltage

GND

−

Ground