5

HV2221

Supertex inc.

1235 Bordeaux Drive, Sunnyvale, CA 94089

Tel: 408-222-8888

www.supertex.com

Truth Table

D0

D1

D2

D3

D4

D5

D6

D7

LE

CLR SW0 SW1 SW2 SW3 SW4 SW5 SW6 SW7

L

L

L

Off

H

L

L

On

L

L

L

Off

H

L

L

On

L

L

L

Off

H

L

L

On

L

L

L

Off

H

L

L

On

L

L

L

Off

H

L

L

On

L

L

L

Off

H

L

L

On

L

L

L

Off

H

L

L

On

L

L

L

Off

H

L

L

On

X

X

X

X

X

X

X

X

H

L

Hold Previous State

X

X

X

X

X

X

X

X

X

H

All Switches Off

Notes:

1.

The eight switches operate independently.

2.

Serial data is clocked in on the L to H transition of the CLK.

3.

The switches go to a state retaining their present condition at the rising edge of LE. When LE is low the shift register data flow through the latch.

4.

D

5.

Shift register clocking has no effect on the switch states if LE is high.

6.

The CLR clear input overrides all other inputs.

Logic Timing Waveforms

DATA IN

LE

CLK

DATA OUT

OFF

ON

V

OUT

(typ)

50%

50%

50%

50%

t

WLE

t

SD

t

SU

t

h

50%

50%

t

OFF

50%

t

DO

t

ON

t

WCL

CLR

D

N+1

D

N

D

N-1

50%

50%

90%

10%