AT22LV10(L)

7

Preload of Registered Outputs

The registers in the AT22LV10 and AT22LV10L are pro-

vided with circuitry to allow loading of each register asyn-

chronously with either a high or a low. This feature will

simplify testing since any state can be forced into the regis-

will force the register high; a V

dent of the polarity bit (C0) setting. The preload state is

entered by placing an 11.5V to 13V signal on pin 8 on

DIPs, and pin 10 on SMPs. When the clock pin is pulsed

high, the data on the I/O pins is placed into the ten regis-

ters.

Power-Up Reset

The registers in the AT22LV10 and AT22LV10L are

designed to reset during power up. At a point delayed

slightly from VCC crossing 2.5V, all registers will be reset

to the low state. The output state will depend on the polarity

of the output buffer.

This feature is critical for state machine initialization. How-

ever, due to the asynchronous nature of reset and the

uncertainty of how VCC actually rises in the system, the fol-

lowing conditions are required:

1.

2.

After reset occurs, all input and feedback setup

times must be met before driving the clock pin high,

and

3.

The clock must remain stable during t

Note:

1. Typical values for nominal supply voltage. This parameter is only sampled and is not 100% tested.

Erasure Characteri

The entire fuse array of an AT22LV10 or AT22LV10L is

erased after exposure to ultraviolet light at a wavelength of

2537 Å. Complete erasure is assured after a minimum of

20 minutes exposure using 12,000

spaced one inch away from the chip. Minimum erase time

for lamps at other intensity ratings can be calculated from

prevent unintentional erasure, an opaque label is recom-

mended to cover the clear window on any UV erasable

PLD which will be subjected to continuous fluorescent

indoor lighting or sunlight.

Level forced on registered output

pin during preload cycle

Register state after

cycle

V

IH

High

V

IL

Low

Parameter

Description

Min

Typ

Max

Units

Power-Up

Reset Time

600

1000

ns

Pin Capacitance

Typ

Max

Units

Conditions

C

IN

58

pF

V

C

OUT

68

pF

V