_______________________SCR Latchup

Like all junction-isolated CMOS circuits, the ICL7665 has

an inherent four-layer or SCR structure that can be

triggered into destructive latchup under certain con-

ditions. Avoid destructive latchup by following these

precautions:

greater than V+ or less than ground, limit the input

current to 500

µA maximum. Usually, an input volt-

age divider resistance can be chosen to ensure

the input current remains below 500

µA, even

when the input voltage is applied before the

ICL7665 V+ supply is connected.

2) Limit the rate-of-rise of V+ by using a bypass

capacitor near the ICL7665. Rate-of-rise SCRs

rarely occur unless: a) the battery has a low

impedance—as is the case with NiCd and lead

acid batteries; b) the battery is connected directly

to the ICL7665 or is switched on via a mechanical

switch with low resistance; or c) there is little or no

input filter capacitance near the ICL7665. In line-

powered systems, the rate-of-rise is usually limited

by other factors and will not cause a rate-of-rise

SCR action under normal circumstances.

3) Limit the maximum supply voltage (including tran-

sient spikes) to 18V. Likewise, limit the maximum volt-

age on OUT1 and OUT2 to +18V and the maxi-

mum voltage on HYST1 and HYST2 to 18V below V+.

Microprocessor Voltage Monitor with

Dual Over/Undervoltage Detection

PART

TEMP. RANGE

PIN-PACKAGE

ICL7665AC/D

0°C to +70°C

Dice*

ICL7665EPA

-40°C to +85°C

8 Plastic DIP

ICL7665AEPA

-40°C to +85°C

8 Plastic DIP

ICL7665ESA

-40°C to +85°C

8 SO

ICL7665AESA

-40°C to +85°C

8 SO

___________________Chip Topography

_Ordering Information (continued)

ICL7665IPA

-20°C to +85°C

8 Plastic DIP

ICL7665IJA

-20°C to +85°C

8 CERDIP

*Contact factory for dice specifications.

OUT2

V+

HYST1

0.066"

(1.42mm)

0.084"

(1.63mm)

SET1

V-

SET2

HYST2

OUT1

ICL7665CTV

0°C to +70°C

8 TO-99

ICL7665ACTV

0°C to +70°C

8 TO-99

ICL7665BCTV

0°C to +70°C

8 TO-99

TRANSISTOR COUNT: 38

SUBSTRATE CONNECTED TO V+.

Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are

implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.

12 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600

© 1997 Maxim Integrated Products

Printed USA

is a registered trademark of Maxim Integrated Products.