MC145017

Rev 5, 05/2005

Freescale Semiconductor

Technical Data

© Freescale Semiconductor, Inc., 2005. All rights reserved.

Low-Power CMOS

Ionization Smoke Detector IC

with Temporal Pattern Horn Driver

The MC145017, when used with an ionization chamber and a small number

of external components, will detect smoke. When smoke is sensed, an alarm is

sounded via an external piezoelectric transducer and internal drivers. This circuit

is designed to operate in smoke detector systems that comply with UL217 and

UL268 specifications.

Features

•

Ionization Type with On-Chip FET Input Comparator

•

Piezoelectric Horn Driver

•

Guard Outputs on Both Sides of Detect Input

•

Input-Production Diodes on the Detect Input

•

Low-Battery Trip Point, Internally Set, can be Altered Via External Resistor

•

Detect Threshold, Internally Set, can be Altered Via External Resistor

•

Pulse Testing for Low Battery Uses LED for Battery Loading

•

Comparator Outputs for Detect and Low Battery

•

Internal Reverse Battery Protection

•

Supports NFPA 72, ANSi 53.41, and ISO 8201 Audible Emergency

Evacuation Signals

ORDERING INFORMATION

Device

Case No.

Package

MC145017P

648-08

Plastic Dip

MC145017

P SUFFIX

PLASTIC DIP

CASE 648-08

LOW-POWER CMOS IONIZATION

SMOKE DETECTOR IC WITH

TEMPORAL PATTERN

HORN DRIVER

Figure 1. . Pin Connections

16

15

14

13

12

11

10

9

1

2

3

4

5

6

7

8

Detect

Comp. Out

N/C

Low V Set

Low V

Comp. Out

LED

Timing

Resistor

Feedback

Guard Hi-Z

Detect Input

Guard Lo-Z

Sensitivity Set

Osc Capacitor

Silver

Brass