PHOTOELECTRIC SMOKE DETECTOR
WITH INTERCONNECT AND TIMER
The A5358CA 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 and British Standard BS 5446,
Part 1.
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 10
s window.
A special three-stage speedup sensing scheme is incorporated to
minimize the time to an audible alarm and also to reduce false trigger-
ing. Also, two consecutive cycles of degraded chamber sensitivity are
required for a warning signal to occur.
The A5358CA 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
C to +75
C.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
OSC. &
TIMING
HORN
DRIVER
TEST
DETECT
HUSH
OSC. CAP.
HORN
HORN
SUPPLY
V
SS
C
I / O
C
STROBE
+ SUPPLY
V
DD
TIMING RES.
FEEDBACK
1
2
LED
IRED
LOGIC
1
2
Data Sheet
26110.10A
Dwg. PC-007
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
C to +75
C
Storage Temperature Range,
T
S
................................... -55
C to +125
C
CAUTION: CMOS devices have input static
protection but are susceptible to damage if exposed
to extremely high static electrical charges.
Always order by complete part number: A5358CA .
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
Built-In Circuits to Reduce False Triggering
s
6 V to 12 V Operating Voltage Range
s
ESD-Protection Circuitry on All Pins
5358
5358
PHOTOELECTRIC SMOKE DETECTOR
with INTERCONNECT and TIMER
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
FUNCTIONAL BLOCK DIAGRAM
4
STROBE
SUPPLY
14
VSS
9 V
+ SUPPLY
I / O
TIMING RES.
FEEDBACK
DETECT
OSC. CAP.
POWER-ON
RESET
OSCILLATOR
& TIMING
LOGIC
+
+
HORN 1
HORN
2
LED
TEST
+V
+V
V
DD
16
7
11
10
9
8
13
12
5
3
V
DD
Dwg. FC-006
1
2
LOW BATTERY
C1
C2
HUSH
15
6
IRED
PHOTO AMP
V DD
BAND-GAP
REFERENCE
Copyright 1995, 1996 Allegro MicroSystems, Inc.
Test
Limits
Characteristic
Symbol
Test Conditions
Pin
V
DD
Min.
Typ.
Max.
Units
Supply Voltage Range
V
DD
5
6.0
12
V
Operating Supply Current
I
DD
Average Standby
5
12
12
A
Configured per Figure 1
During Strobe ON, I
RED
OFF,
5
12
2.0
mA
Configured per Figure 1
During Strobe ON, I
RED
ON,
5
12
3.0
mA
Configured per Figure 1
Low-Level Input Voltage
V
IL
7
9
1.5
V
10
9
2.7
V
16
9
7.0
V
15
9
0.5
V
High-Level Input Voltage
V
IH
7
9
3.2
V
10
9
6.3
V
16
9
8.5
V
15
9
1.6
V
Input Leakage High
I
IH
V
IN
= V
DD
, Strobe Active,
1, 2
12
100
nA
Pin 12 @ V
DD
V
IN
= V
DD
3, 10, 12
12
100
nA
Input Leakage Low
I
IL
V
IN
= V
ST
, Strobe Active,
1, 2, 3
12
-100
nA
Pin 12 @ V
DD
V
IN
= V
SS
10, 12
12
-100
nA
15, 16
12
-1.0
A
Input Pull-Down Current
I
IN
V
IN
= V
DD
16, 15
9
0.25
10
A
No Local Smoke, V
IN
= V
DD
7
9
20
80
A
No Local Smoke, V
IN
= 17 V
7
12
140
A
Low-Level Output Voltage
V
OL
I
O
= 10 mA
11
6.5
0.6
V
I
O
= 16 mA
8, 9
6.5
1.0
V
I
O
= 5 mA
13
6.5
0.5
V
High-Level Output Voltage
V
OH
I
O
= -16 mA
8, 9
6.5
5.5
V
Strobe Output Voltage
V
ST
Inactive I
O
= -1
A
4
12
V
DD
- 0.1
V
Active, I
O
= 100
A to 500
A
4
9
V
DD
- 5.25
V
DD
- 4.75
V
Continued...
DC ELECTRICAL CHARACTERISTICS at T
A
= -25
C to +75
C*, V
SS
= 0 V, in typical application
(unless otherwise noted).
5358
PHOTOELECTRIC SMOKE DETECTOR
with INTERCONNECT and TIMER
5358
PHOTOELECTRIC SMOKE DETECTOR
with INTERCONNECT and TIMER
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Test
Limits
Characteristic
Symbol
Test Conditions
Pin
V
DD
Min.
Typ.
Max.
Units
Line Regulation
V
ST(
VDD)
Active, V
DD
= 6 V to 12 V
4
-60
dB
Strobe Temperature Coeff.
ST
V
DD
= 6 V to 12 V
4
0.01
%/
C
I
RED
Output Voltage
V
IRED
Inactive I
O
= 1
A, T
A
= +25
C
6
12
0.1
V
Active I
O
= -6 mA, T
A
= +25
C
6
9
2.85
3.1
3.35
V
Line Regulation
V
IRED(
VDD)
Active, V
DD
= 6 V to 12 V
6
-35
dB
I
RED
Temperature Coefficient
IRED
V
DD
= 6 V to 12 V
6
+0.40
%/
C
High-Level Output Current
I
OH
V
DD
= Alarm, I/O active,
7
9
-4.0
mA
V
O
= V
DD
- 2 V
OFF Leakage Current High
I
OZ
V
O
= V
DD
11, 13
12
1.0
A
OFF Leakage Current Low
I
OZ
V
O
= V
SS
11, 13
12
-1.0
A
Low V
DD
Alarm Threshold
V
DD(th)
5
-
6.9
7.2
7.5
V
Common Mode Voltage
V
IC
Any Alarm Condition
1, 2, 3
-
V
DD
- 4
V
DD
- 2
V
Smoke Comparator Ref. Volt.
V
REF
Any Alarm Condition
Internal
-
V
DD
- 3.7
V
DD
- 3.3
V
DC ELECTRICAL CHARACTERISTICS, continued
AC ELECTRICAL CHARACTERISTICS at T
A
= -25
C to +75
C*, V
SS
= 0 V, in typical application
(unless otherwise noted).
Test
Limits
Characteristic
Symbol
Test Conditions
Pin
V
DD
Min.
Typ.
Max.
Units
Oscillator Period
t
osc
12
9
9.4
10.5
11.5
ms
Led Pulse Period
t
led1
No Local or Remote Smoke
11
9
39
48
s
t
led4
Remote Smoke Only
11
9
None
t
led6
Local Smoke or Test
11
9
0.60
0.67
0.74
s
t
led7
Timer Mode, No Alarm
11
9
9.67
10.8
11.8
s
Led Pulse Width
t
w(led)
11
9
9.5
11.5
ms
Continued...
* Limits over the operating temperature range are based on characterization data.
Characteristics are production tested at +25
C only.
Typical values are at +25
C and are given for circuit design information only.
Test
Limits
Characteristic
Symbol
Test Conditions
Pin
V
DD
Min.
Typ.
Max.
Units
Strobe Pulse Period
t
st1
No Local or Remote Smoke
4
9
9.6
11.9
s
t
st2
After 1 of 3 Valid Samples
4
9
2.42
2.70
2.96
s
t
st3
After 2 of 3 Valid Samples
4
9
1.21
1.34
1.47
s
and During Local Alarm
t
st4
Remote Alarm
4
9
9.67
10.8
11.8
s
t
st5
Chamber Test or Low Supply
4
9
38.9
47.1
s
Test, No Local Alarm
t
st6
Pushbutton Test, No Alarm
4
9
300
336
370
ms
Strobe Pulse Width
t
w(st)
4
9
9.5
11.5
ms
I
RED
Pulse Period
t
ired1
No Local or Remote Smoke
6
9
9.6
11.9
s
t
ired2
After 1 of 3 Valid Samples
6
9
2.42
2.70
2.96
s
t
ired3
After 2 of 3 Valid Samples
6
9
1.21
1.34
1.47
s
and During Local Alarm
t
ired4
Remote Alarm
6
9
9.67
10.8
11.8
s
t
ired5
Chamber Test, No Local Alarm
6
9
38.9
47.1
s
t
ired6
Pushbutton Test, No Alarm
6
9
300
336
370
ms
I
RED
Pulse Width
t
w(ired)
6
9
94
116
s
I
RED
Rise Time
t
r(ired)
10% to 90%
6
30
s
I
RED
Fall Time
t
f(ired)
90% to 10%
6
200
s
I/O to Active Delay
t
d(io)
Local Alarm
7
9
0
s
Rising Edge on I/O to Alarm
t
r(io)
No Local Alarm
7
9
1.34
s
Horn Warning Pulse Period
t
horn
Low Supply and Degraded
8, 9
9
38.9
47.1
s
Chamber Sensitivity
Horn Warning Pulse Width
t
w(horn)
Low Supply and Degraded
8, 9
9
9.5
11.5
ms
Chamber Sensitivity
Horn ON Time
t
on(horn)
Local or Remote Alarm
8, 9
9
252
ms
Horn OFF Time
t
off(horn)
Local or Remote Alarm
8, 9
9
84
ms
AC ELECTRICAL CHARACTERISTICS, continued.
* Limits over the operating temperature range are based on characterization data.
Characteristics are production tested at +25
C only.
Typical values are at +25
C and are given for circuit design information only.
5358
PHOTOELECTRIC SMOKE DETECTOR
with INTERCONNECT and TIMER
PDF 
ZIP