A5364: Smoke Detector with Interconnect

A5364
Ionization Smoke Detector with Interconnect
Discontinued Product
This device is no longer in production. The device should not be
purchased for new design applications. Samples are no longer available.
Date of status change: November 2, 2010
Recommended Substitutions:
For existing customer transition, and for new customers or new applications, contact Allegro Sales.
NOTE: For detailed information on purchasing options, contact your
local Allegro field applications engineer or sales representative.
Allegro MicroSystems, Inc. reserves the right to make, from time to time, revisions to the anticipated product life cycle plan
for a product to accommodate changes in production capabilities, alternative product availabilities, or market demand. The
information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, Inc. assumes no responsibility for its use; nor for any infringements of patents or other rights of third parties which may result from its use.
A5364
Ionization Smoke Detector
with Interconnect
Features and Benefits
Description
▪ Low average standby current for long battery life
▪ Interconnect up to 125 detectors
▪ Piezoelectric horn driver
▪ Guard outputs for detector input
▪ Pulse testing for low battery
▪ Power-on reset (POR)
▪ Internal reverse battery protection
▪ Built-in hysteresis reduces false triggering
▪ Temporal horn pattern, per UL217, NFPA72, and ISO8201
▪ UL Recognized for UL217 or UL268 applications
The A5364 is a low-current, BiCMOS circuit providing all of
the required features for an ionization-type smoke detector.
A networking capability allows as many as 125 units to be
interconnected so that if any unit senses smoke all units will
sound their alarm. In addition, special features are incorporated
to facilitate alignment and test of the finished smoke detector.
The device is Recognized by Underwriters Laboratories for
use in smoke alarms that comply with Standard UL217 or
UL268, per file #S2113.
The internal oscillator and timing circuitry keep standby power
to a minimum by powering down the device for 1.66 seconds
and sensing for smoke for only 10 ms. Every 24 on-off cycles,
a check is made for a low battery condition. By substituting
other types of sensors or a switch for the ionization detector,
this very-low–power device can be used in numerous other
battery-operated safety/security applications.
Package: 16-pin DIP (suffix A):
The A5364 is supplied in a low-cost 16-pin dual in-line plastic
package (DIP). It is rated for continuous operation over the
temperature range of –10°C to 60°C. The Pb (lead) free version
(suffix –T) has 100% matte tin leadframe plating.
Not to scale
Typical Application
200 kΩ
GUARD2
1 NC
200 Ω
To / from
other units
B
2
3
DETECT IN
I/O
A5364
LOW-V SET
4 NC
330 Ω
9V
5
6
8.2 MΩ
1 μF
7
8
LED
GUARD1
SENSITIVITY SET
OSC CAP
VDD
HORN2
TIMING RES
HORN1
FEEDBACK
VSS
16
200 k Ω
15
Push
to Test
14
13
B A resistor to VSS or VDD may
be added to this pin to modify
low battery voltage threshold.
C Value of component will vary, based on
the piezoelectric horn used.
A
12
0.1 μF
11
10
9
1.5 MΩ
C
220 kΩ
C
26110.7H
A Use an external resistor to adjust
sensitivity for a particular smoke chamber.
0.001 μF
C
Ionization Smoke Detector
with Interconnect
A5364
Selection Guide
Part Number
Pb-Free
Packing
–
25 pieces per tube
A5364CA
Absolute Maximum Ratings*
Characteristic
Symbol
Supply Voltage Range
Input Voltage Range
Reverse Battery Condition Duration
Rating
Units
VDD
Referenced to VSS
–0.5 to 15
V
VIN
Referenced to VSS
–0.3 to VDD+ 0.3
V
20
s
IIN
10
mA
tRBAT
Input Current
Operating Ambient Temperature
Junction Temperature
Storage Temperature Range
Notes
10.5 V
TA
–10 to 60
ºC
TJ(max)
150
ºC
Tstg
–55 to 125
ºC
* CAUTION: BiCMOS devices have input static protection but are susceptible to damage when exposed to extremely high static electrical charges.
THERMAL CHARACTERISTICS
Characteristic
Symbol
Package Thermal Resistance
RθJA
Test Conditions*
Value Units
4-layer PCB based on JEDEC standard
38
ºC/W
*Additional thermal information available on Allegro website.
Terminal List Table
Number
Pin-out Diagram
NC 1
I/O 2
LOW-V SET 3
NC 4
16 GUARD2
15 DETECT IN
14 GUARD1
13 SENSITIVITY SET
1
Name
NC
Function
2
I/O
3
LOW-V SET
4
NC
No connection
5
LED
Output to drive visible LED
6
VDD
Positive supply voltage
7
TIMING RES
Terminal for timing resistor, sets internal bias
(affects timing)
Input for driving piezoelectric horn
No connection
Input/output to interconnected detectors
Optionally used with a resistor to adjust low-battery
threshold
LED 5
12 OSC CAP
8
FEEDBACK
VDD 6
11 HORN2
9
10 HORN1
VSS
TIMING RES 7
10
HORN1
Output for driving piezoelectric horn
11
HORN2
Complementary output for driving piezoelectric horn
12
OSC CAP
13
SENSITIVITY SET
14
GUARD1
15
DETECT IN
16
GUARD2
FEEDBACK 8
9 VSS
Negative supply voltage
Terminal for charging/discharging an external
capacitor to run the oscillator
Optionally used with a resistor to adjust sensitivity
for a specific chamber
Active guard 1 for detector input
Input from detector chamber
Active guard 2 for detector input
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
Copyright © 2001, 2002 Allegro MicroSystems, Inc.
2
Ionization Smoke Detector
with Interconnect
A5364
Functional Block Diagram
I/O
+Supply
9V
VDD
FEEDBACK
VDD
Band
Gap
LBSamp
HORN2
HORN1
Low Battery
Sample
Low Battery
Comparator
600 kΩ
_
LED
Logic
LOW-V SET
+ VDD
+
500 kΩ
Power-on
Reset
+
_
SENSITIVITY SET
SSamp
Smoke
Comparator
Smoke
Sample
1.1 MΩ
TIMING RES
LBSamp
SSamp
Oscillator
and Timing
+ VDD
OSC CAP
-Supply
VSS
+
_
GUARD1
DETECT IN
GUARD2
+ VDD
ION CHAMBER
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
3
Ionization Smoke Detector
with Interconnect
A5364
ELECTRICAL CHARACTERISTICS1,2 at TA = 25°C, VDD = 9.0 V, VSS = 0 V, COSCCAP = 0.1 μF,
RTIMINGRES = 8.2 MΩ (unless otherwise noted)
Characteristic
Supply Voltage Range
Supply Current
Detector Input Current
Symbol
VDD
IDD
Oscillator Pulse Width
IDETECTIN
VOS(GUARD1)
VOS(GUARD2)
VOS
VHYS
VCM(guard)
VCM
ZAG1
ZAG2
tosc
tosc(alarm)
tw(osc)
Low-Battery Threshold
VDD(th)
Input Offset Voltage
Hysteresis
Common Mode Range
Active Guard Impedance
Oscillator Period
Sensitivity Adjust Voltage
VSET
VOL
Horn Output Voltage
VOH
Horn Output On-Time
ton(horn)
tw(horn)
toff1(horn)
Horn Output Off-Time
LED Output-On Current
LED Output On-Time
LED Output Off-Time
toff2(horn)
thorn
ILED
tw(LED)
tLED1
tLED3
tLED4
Test Conditions
Operating
VDD = 9.0 V, no alarm, no loads
VDD = 12 V, no alarm, no loads
0% to 40% RH, VIN = 0 to 9.0 V
Active GUARD1
Active GUARD2
Detect comparator
No alarm to alarm
Guard amplifier
Smoke comparator
GUARD1 to VSS
GUARD2 to VSS
No alarm
Local or remote alarm
TA = 0°C to 50°C,
LOW-V SET open circuit
VSENSITIVITYSET / VDD,
SENSITIVITY SET open circuit
IOUT = 16 mA, VDD = 9.0 V
IOUT = 16 mA, VDD = 7.2 V
IOUT = –16 mA, VDD = 9.0 V
IOUT = –16 mA, VDD = 7.2 V
Local or remote alarm
Low battery
Local or remote alarm
(see Timing Diagrams section)
Local or remote alarm
(see Timing Diagrams section)
Low battery
VDD = 7.2 V, VLED = 1.0 V
No alarm, in standby
Local alarm or test alarm
Remote alarm, no local smoke
Test Pin
6
6
6
15
14, 15
16, 15
15, 13
13
14, 15
13, 15
14
16
12
12
12
Min.
6.0
—
—
—
—
—
—
90
2.0
0.5
—
—
1.34
37.50
8.0
Typ.
9.0
5.0
—
—
—
—
—
130
—
—
10
500
1.67
41.67
10
Max.
12
9.0
12
±1.0
±100
±100
±50
170
VDD – 0.5
VDD – 2.0
—
—
2.00
45.84
12
Units
V
μA
μA
pA
mV
mV
mV
mV
V
V
kΩ
kΩ
s
ms
ms
6
7.2
—
7.8
V
13
48.5
50
51.5
%VDD
10, 11
10, 11
10, 11
10, 11
10,11
10, 11
—
—
8.5
6.3
450
8.0
0.1
—
8.8
—
500
10
0.5
0.9
—
—
550
12
V
V
V
V
ms
ms
10, 11
450
500
550
ms
10, 11
1350
1500
1650
ms
10, 11
5
5
5
5
32
10
8.0
32
0.76
48
—
12
48
1.14
s
mA
ms
s
s
5
—
40
—
10
40
0.97
No LED
pulses
—
s
Continued on the next page…
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
4
Ionization Smoke Detector
with Interconnect
A5364
ELECTRICAL CHARACTERISTICS1,2 (continued) at TA = 25°C, VDD = 9.0 V, VSS = 0 V, COSCCAP = 0.1 μF,
RTIMINGRES = 8.2 MΩ (unless otherwise noted)
Characteristic
Symbol
Test Conditions
Test Pin
Min.
Typ.
Max.
Units
No alarm, VI/O = VDD – 2.0 V
2
25
—
60
μA
IIOL
I/O Current
Local alarm, VI/O = VDD – 2.0 V
2
–7.5
—
—
mA
IIOH
I/O Alarm Voltage
VIH(IO)
External “alarm” in
2
3.0
—
—
V
I/O Delay
tr(io)
Local or test alarm to I/O active
2
—
3.0
—
s
1Negative current is defined as coming out of the specified device pin (sourcing).
2Alarm (smoke) condition is defined as V
DETECTIN < VSENSITIVITYSET; no alarm (no smoke) condition is defined as VDETECTIN > VSENSITIVITYSET.
Circuit Description
The A5364 is a low-current, BiCMOS circuit providing all of the
required features for an ionization-type smoke detector.
Oscillator
An internal oscillator operates with a period of 1.67 seconds
during no-smoke conditions. Every 1.67 seconds, internal power
is applied to the entire circuit for 10 ms and a check is made for
smoke. Every 24 clock cycles (approximately 40 seconds), the
LED pin is pulsed and a check is made for low battery by comparing VDD to an internal reference. Because very-low currents
are used in the device, the oscillator capacitor at the OSC CAP
pin should be a low-leakage type (PTFE, polystyrene, or polypropylene).
Detector Circuitry
When the voltage on the DETECT IN pin is less than the voltage on the SENSITIVITY SET pin, the A5364 evaluates this as a
smoke condition. During a smoke condition, the resistor divider
network that sets the sensitivity (also referred to as the smoke trip
point) is altered to increase VSENSITIVITYSET by 130 mV typical
(with no external connections on the SENSITIVITY SET pin).
This provides hysteresis and reduces false triggering.
An active guard is provided on GUARD1 and GUARD2, the two
pins adjacent to the detector input, the DETECT IN pin. VGUARD1
and VGUARD2 will be within 100 mV of VDETECTIN. This will
keep surface leakage currents to a minimum and provide a
method of measuring the input voltage without loading the ionization chamber. The active guard amplifier is not power strobed
and thus provides constant protection from surface leakage
currents. The detector input has internal diode protection against
electrostatic damage.
Alarm Circuitry
If smoke is detected, the oscillator period changes to 40 ms and
the horn is enabled. The horn output follows a temporal horn
pattern of nominally: 0.5 s on, 0.5 s off, 0.5 s on, 0.5 s, 0.5 s on,
1.5 s off. During the off-time, smoke is checked and further alarm
output will be inhibited if smoke is not sensed. During a smoke
condition, the low-battery alarm is inhibited and the LED is
pulsed approximately once every second.
Sensitivity Adjust
The detector sensitivity to smoke is set internally by a voltage
divider connected between VDD and VSS. The sensitivity can,
however, be externally adjusted to the individual characteristics
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
5
Ionization Smoke Detector
with Interconnect
A5364
of the ionization chamber by connecting a resistor between the
SENSITIVITY SET pin and either the VDD or VSS pins.
With no external connections on the SENSITIVITY SET pin,
while the A5364 is checking for smoke:
VSENSITIVITYSET = VDD / 2 .
To increase sensitivity, a resistor can be connected between
SENSITIVITY SET and VDD, with the value:
RSENSITIVITYSET = 1.1E6 × K / (1 – K) ,
where
K = VDD / VSENSITIVITYSET – 1 .
To decrease sensitivity, a resistor can be connected between
SENSITIVITY SET and VSS, with the value:
RSENSITIVITYSET = 1.1E6 × K / (1 – K) ,
where
K = 1 / (VDD / VSENSITIVITYSET – 1) .
Low Battery
The low battery condition threshold is set internally by a voltage
divider connected between VDD and VSS. The threshold can
be externally adjusted by connecting a resistor between the
LOW-V SET pin and either the VDD or VSS pins.
To increase the threshold, a resistor can be connected between
LOW-V SET and VSS. Given an initial threshold, V(th)init (nominally 7.5 V), and a target threshold, V(th)set , the resistor should
have the value:
RLOWVSET = 600E3 × K / (1 – 0.375 × K) ,
where
K = 1 / (V(th)set / [0.727 × V(th)init] – 1) .
To decrease the threshold, a resistor can be connected between
LOW-V SET and VDD. Given an initial threshold, V(th)init (nominally 7.5 V), and a target threshold, V(th)set , the resistor should
have the value:
RLOWVSET = 960E3 × K / (0.6 – 1.6 × K) ,
where
K = V(th)set / (0.727 × V(th)init) – 1 .
The battery voltage level is checked approximately every 40 seconds during the (approximately) 10 mA, 10 ms LED pulse. If an
LED is not used, it should be replaced with an equivalent resistor
(typically 500 to 1000 Ω) such that the battery loading remains
about 10 mA.
I/O
A connection to the I/O pin allows multiple smoke detectors to
be interconnected. If any single unit detects smoke, its I/O pin is
driven high (after a nominal 3 s delay), and all connected units
will sound their associated horns. When the I/O pin is driven
high by another device, the oscillator immediately speeds up to
its 41.7 ms period. The remainder of the sped-up clock cycle,
and two additional consecutive clock cycles with I/O high are
required to cause an alarm. If the I/O pin falls below its threshold
at any time during those (approximately) 83.4 ms, an internal
latch is reset and there will not be an alarm. Thus, the I/O must
remain high for (approximately) 93.9 ms in order to cause an
alarm. This filtering provides significant immunity to I/O noise.
The LED is suppressed when an alarm is signaled from an
interconnected unit, and any local alarm condition causes the I/O
pin to be ignored as an input. This pin has an on-chip pulldown
device and must be left unconnected if not used.
Testing
On power-up, all internal counters are reset. Internal test circuitry allows low battery check by holding the FEEDBACK and
OSC CAP pins low during power-up, then reducing VDD and
monitoring the HORN1 pin. HORN1 will be driven high when
VDD falls below the low-battery threshold. All functional tests
can be accelerated by driving the OSC CAP pin with a 2 kHz
square wave. The 10 ms strobe period must be maintained for
proper operation of the comparator circuitry.
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
6
Ionization Smoke Detector
with Interconnect
A5364
Timing Diagrams
(Not to scale)
Test event
Standby Mode
OSC CAP Pin
tosc
tw(osc)
Internal Clock
Smoke Sample
Low Battery Test
tw(led)
tled1
LED Pin
LED off (High-Z)
LED on
Low Battery Condition
(Low battery)
VDD Pin
Low Battery Test
tled1
tw(led)
LED Pin
LED off (High-Z)
thorn
tw(horn)
LED on
Horn Enable
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
7
Ionization Smoke Detector
with Interconnect
A5364
Local Smoke Detection/Test Alarm Condition
tosc(alarm)
tw(osc)
OSC CAP Pin
Test event
Internal Clock
Smoke Sample
LED Pin
24 clock cycles
Smoke Sample
Smoke Chamber
tw(led)
LED Pin
(no smoke)
V DETECTIN < VSENSITIVITYSET (smoke)
tled3
LED off (High-Z)
LED on
toff1(horn)
toff 2(horn)
ton(horn)
Horn Enable
tr(io)
(Output)
I/O Pin
Remote Alarm Condition
tosc(alarm)
OSC CAP Pin
Internal Clock
I/O Pin
LED Pin
tw(osc)
LED off (High-Z)
ton(horn)
toff2(horn)
toff1(horn)
Horn Enable
I/O Pin
(Input)
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
8
Ionization Smoke Detector
with Interconnect
A5364
Package A, 16-Pin DIP
19.05
+0.64
–0.38
0.25
+0.10
–0.05
16
6.35
A
1
+0.76
–0.25
7.62 BSC
10.92 MAX
2
Branded Face
3.30
+1.65
–0.38
SEATING
PLANE
0.38 MIN
C
5.33 MAX
3.30
+0.51
–0.38
2.54 BSC
0.13 MIN
+0.25
1.52
–0.38
16X 0.46±0.10
0.25 M C
A
Terminal #1 mark area
For Reference Only; not for tooling use (reference MS-001BB)
Dimensions in millimeters
Dimensions exclusive of mold flash, gate burrs, and dambar protrusions
Exact case and lead configuration at supplier discretion within limits shown
Allegro MicroSystems offers an industry-leading range of ionization
and photoelectric smoke detector ICs. For a current listing, please visit
our website at:
www.allegromicro.com
Copyright ©2001-2009, Allegro MicroSystems, Inc.
The products described here are manufactured under one or more U.S. patents or U.S. patents pending.
Allegro MicroSystems, Inc. reserves the right to make, from time to time, such departures from the detail specifications as may be required to permit improvements in the performance, reliability, or manufacturability of its products. Before placing an order, the user is cautioned to verify that the
information being relied upon is current.
Allegro’s products are not to be used in life support devices or systems, if a failure of an Allegro product can reasonably be expected to cause the
failure of that life support device or system, or to affect the safety or effectiveness of that device or system.
The information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, Inc. assumes no responsibility for its use;
nor for any infringement of patents or other rights of third parties which may result from its use.
For the latest version of this document, visit our website:
www.allegromicro.com
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
9
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