R&E International

A Subsidiary of Microchip Technology Inc.

RE46C126

CMOS Ionization Smoke Detector ASIC with Interconnect

Product Specification

© 2009 Microchip Technology Inc.

DS22170A-page 1

General Description

The RE46C126 is low power CMOS ionization type

smoke detector IC. With few external components this

circuit will provide all the required features for an

ionization type smoke detector.

An internal oscillator strobes power to the smoke

detection circuitry for 10.5mS every 1.66 seconds to

keep standby current to a minimum. A check for a low

battery condition is performed every 40 seconds when

in standby. . A 2/3 duty cycle continuous horn pattern is

used for the alarm condition.

An interconnect pin allows multiple detectors to be

connected such that when one unit alarms all units will

sound.

Although this device was designed for smoke detection

utilizing an ionization chamber it can be used in a

variety of security applications.

Utilizing low power CMOS technology the RE46C126

was designed for use in smoke detectors that comply

with Underwriters Laboratory Specification UL217 and

UL268.

Features

•

Guard Outputs for Ion Detector Input

•

+/-0.75pA Detect Input Current

•

Internal Reverse Battery Protection

•

Internal Low Battery Detection

•

Low Quiescent Current Consumption (<6.5uA)

•

Available in 16L PDIP or 16L N SOIC

•

ESD Protection on all Pins

•

Interconnect up to 40 Detectors

•

Compatible with MC14468

•

Available in Standard Packaging or RoHS

Complaint Pb Free Packaging

Pin Configuration

16

1

GUARD2

DETCOMP

2

DETECT

IO

15

3

GUARD1

LBADJ

14

4

VSEN

STROBE

13

ABSOLUTE MAXIMUM RATINGS

PARAMETER

SYMBOL

VALUE

UNITS

Supply Voltage

15

V

Input Voltage Range Except FEED, IO

V

FEED Input Voltage Range

-10 to +22

V

IO Input Voltage Range

-.3 to 17

V

Reverse Battery Time

5

S

Input Current except FEED

10

mA

Operating Temperature

-10 to 60

°C

Storage Temperature

-55 to 125

°C

Maximum Junction Temperature

150

°C

Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are

stress ratings only and operation at these conditions for extended periods may affect device reliability.

This product utilizes CMOS technology with static protection; however proper ESD prevention procedures should be used

when handling this product. Damage can occur when exposed to extremely high static electrical charge

OSCAP

5

12

LED

VDD

RBIAS

FEED

6

HS

11

7

HB

10

VSS

8

9