SN65518, SN75518

VACUUM FLUORESCENT DISPLAY DRIVERS

SLDS004B – MARCH 1983 – REVISED MAY 1990

4–3

POST OFFICE BOX 655303

FUNCTION TABLE

CONTROL INPUTS

SHIFT REGISTERS

LATCHES

OUTPUTS

FUNCTION

CLOCK

LATCH

ENABLE

STROBE

SHIFT REGISTERS

R1 THRU R32

LATCHES

LC1 THRU LC32

SERIAL

Q1 THRU Q32

Load

↑

No

↑

X

X

X

X

Load and shift†

No change

Determined by

LATCH ENABLE‡

R32

Determined by STROBE

Latch

X

X

L

H

X

X

As determined

above

Stored data

New data

R32

Determined by STROBE

Strobe

X

X

X

X

H

L

As determined

above

Determined by

LATCH ENABLE‡

R32

All L

LC1 thru LC32, respectively

H = high level,

L = low level,

X = irrelevant,

↑ = low-to-high-level transition.

† R32 and the serial output take on the state of R31, R31 takes on the state of R30, ... R2 takes on the state of R1, and R1 takes on the state of

the data input.

‡ New data enter the latches while LATCH ENABLE is high. These data are stored while LATCH ENABLE is low.

typical operating sequence

CLOCK

Valid

Irrelevant

DATA IN

Invalid

SR

Contents

LATCH

ENABLE

Previously Stored Data

New Data Valid

Latch

Contents

STROBE

Valid

Q Outputs

Valid