5366
PHOTOELECTRIC SMOKE DETECTOR
WITH INTERCONNECT AND TIMER
The A5366CA is a low-current BiCMOS circuit providing all of the
required features for a photoelectric type smoke detector. This device
can be used in conjunction with an infrared photoelectric chamber to
sense scattered light from smoke particles. Special features are
incorporated in the design to facilitate calibration and testing of the
finished detector. The device is designed to comply with Underwriters
Laboratories Specification UL217.
A variable-gain photo amplifier can be directly interfaced to an
infrared emitter/detector pair. The amplifier gain levels are determined
by two external capacitors that are then internally selected depending
on the operating mode. Low gain is selected during standby and timer
modes. During a local alarm this low gain is increased (internally) by
~10% to reduce false triggering. High gain is used during the push-
button test and during standby to periodically monitor the chamber
sensitivity.
The internal oscillator and timing circuitry keeps standby power to
a minimum by sensing for smoke every 10 seconds in a 100
碌s
window. A special three-stage speedup sensing scheme is incorpo-
rated to minimize the time to an audible alarm and also to reduce false
triggering. Also, two consecutive cycles of degraded chamber sensitiv-
ity are required for a warning signal to occur.
The A5366CA is supplied in a low-cost 16-pin dual in-line plastic
package. It is rated for continuous operation over the temperature
range of -25擄C to +75擄C.
Data Sheet
26110.11*
C1
C2
DETECT
STROBE
+ SUPPLY
IRED
I/O
HORN 1
1
2
3
4
5
6
7
8
HORN
DRIVER
V
DD
LOGIC
OSC. &
TIMING
V
SS
16
15
14
13
12
11
10
9
TEST
HUSH
鈥?SUPPLY
TIMING RES.
OSC. CAP.
LED
FEEDBACK
HORN 2
Dwg. PC-007
The selectable Hush Feature may be covered
by U.S. patent number Re. 33,920. Any sale
or use of the Hush Feature in a smoke alarm
in the U.S. would be a possible infringement
of this patent.
ABSOLUTE MAXIMUM RATINGS
(Voltages are referenced to V
SS
)
Supply Voltage Range,
V
DD
....................................
-0.5 V to +15 V
Input Voltage Range,
V
IN
............................
-0.3 V to V
DD
+ 0.3 V
Input Current, I
IN
...................................
10 mA
Operating Temperature Range,
T
A
.....................................
-25
擄
C to +75
擄
C
Storage Temperature Range,
T
S
...................................
-55
擄
C to +125
擄
C
CAUTION: CMOS devices have input static
protection but are susceptible to damage if exposed
to extremely high static electrical charges.
FEATURES
s
Interconnect Up to 50 Detectors
s
Piezoelectric Horn Driver
s
All Internal Low-Battery Detection
s
Power-ON Reset
s
Internal Timer & Control for Reduced Sensitivity
s
s
s
s
Built-In Circuits to Reduce False Triggering
6 V to 12 V Operating Voltage Range
ESD-Protection Circuitry on All Pins
Temporal Horn Pattern
Always order by complete part number:
A5366CA
.