R&E International
A Subsidiary of Microchip Technology Inc.
RE46C120
CMOS Ionization Smoke Detector ASIC
Product Specification
General Description
The RE46C120 is a low power CMOS ionization type
smoke detector IC. With a 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. The TONE input allows for selection of a
temporal pattern or a 2/3 duty cycle continuous tone.
The temporal horn pattern supports the NFPA 72
emergency evacuation signal.
Although this device was designed for smoke detection
utilizing an ionization chamber it could be used in a
variety of security applications.
© 2009 Microchip Technology Inc. DS22157B-page 1
The RE46C120 is recognized by Underwriters
Laboratories for use in smoke detectors that comply
with specification UL217 and UL268.
Features
• Guard Outputs for Ion Detector Input
• +/-0.75pA Detect Input Current
• Internal Reverse Battery Protection
• Internal Low Battery Detection
• Pin Selectable Horn Pattern
• Low Quiescent Current Consumption (<6.5uA)
• 16L PDIP
• ESD Protection on all Pins
• Compatible with MC145017, MC14467
• UL Recognized per File S24036
• Available in RoHS Compliant Pb Free Packaging
Pin Configuration
16
1
DETCOMP GUARD2
15
2
DETECT N/C
14
3
GUARD1LBADJ
13
4
VSEN TONE
ABSOLUTE MAXIMUM RATINGS
PARAMETER SYMBOL VALUE UNITS
Supply Voltage V
DD
15 V
Input Voltage Range Except FEED V
in
-.3 to V
dd
+.3 V
FEED Input Voltage Range V
infd
-10 to +22 V
Reverse Battery Time T
RB
5 S
Input Current except FEED I
in
10 MA
Operating Temperature T
A
-10 to 60
°C
Storage Temperature T
STG
-55 to 125
°C
Maximum Junction Temperature T
J
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
12
5
OSCAP
LED
VDD
RBIAS
FEED
HS
11
6
HB
VSS
8 9
10
7
