Allegro A5358CA Datasheet

1

C

1

2

C

2

DETECT

STROBE

+ SUPPLY V

HORN

3

4

5

6

IRED

7

I / O

89

1

Data Sheet

26110.10A

5358

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

16

TEST

HUSH

15

V

OSC. &
TIMING

DD

LOGIC

HORN

DRIVER

SS

– SUPPLY

14

TIMING RES.

13

OSC. CAP.

12

11

LED

10

FEEDBACK

HORN

Dwg. PC-007

2

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 push­button 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 µs window.
A special three-stage speedup sensing scheme is incorporated to
minimize the time to an audible alarm and also to reduce false trigger­ing. Also, two consecutive cycles of degraded chamber sensitivity are
required for a warning signal to occur.

ABSOLUTE MAXIMUM RATINGS

(Voltages are referenced to VSS)

Supply Voltage Range,

VDD.................................... -0.5 V to +15 V

Input Voltage Range,

VIN............................ -0.3 V to V

Input Current, IIN................................... 10 mA

Operating Temperature Range,

TA..................................... -25°C to +75°C

Storage Temperature Range,

TS................................... -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.

+ 0.3 V

DD

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.

FEATURES

■ Interconnect Up to 50 Detectors

■ Piezoelectric Horn Driver

■ All Internal Low-Battery Detection

■ Power-ON Reset

■ Internal Timer & Control for Reduced Sensitivity

■ Built-In Circuits to Reduce False Triggering

■ 6 V to 12 V Operating Voltage Range

■ ESD-Protection Circuitry on All Pins

Always order by complete part number: A5358CA .

5358

PHOTOELECTRIC SMOKE DETECTOR
with INTERCONNECT and TIMER

FUNCTIONAL BLOCK DIAGRAM

DETECT

STROBE

+ SUPPLY

9 V

3

C1

1

C2

2

4

6IRED

– SUPPLY

14

V

SS

V

DD

5

BAND-GAP

REFERENCE

+
–

LOW BATTERY

PHOTO AMP

+
–

V

DD

I / O

7

LOGIC

V

DD

15

HUSH

POWER-ON

OSCILLATOR

& TIMING

RESET

16

TEST

FEEDBACK

10

9

HORN

2

8

HORN

1

11

LED

TIMING RES.

13

12

OSC. CAP.

+V

+V

Dwg. FC-006

115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 [phone]
Copyright © 1995, 1996 Allegro MicroSystems, Inc.

5358

PHOTOELECTRIC SMOKE DETECTOR
with INTERCONNECT and TIMER

DC ELECTRICAL CHARACTERISTICS at T

= -25°C to +75°C*, V

A

(unless otherwise noted).

Test Limits

Characteristic Symbol Test Conditions Pin V

Supply Voltage Range V
Operating Supply Current I

Low-Level Input Voltage V

High-Level Input Voltage V

DD

DD

IH

Average Standby 5 12 – – 12 µA
Configured per Figure 1

During Strobe ON, I

OFF, 5 12 – – 2.0 mA

RED

Configured per Figure 1
During Strobe ON, I

ON, 5 12 – – 3.0 mA

RED

Configured per Figure 1

IL

5 – 6.0 – 12 V

79––1.5V
10 9 – – 2.7 V
16 9 – – 7.0 V
15 9 – – 0.5 V

793.2––V
10 9 6.3 – – V
16 9 8.5 – – V
15 9 1.6 – – V

= 0 V, in typical application

SS

Min. Typ. Max. Units

DD

Input Leakage High I

Input Leakage Low I

Input Pull-Down Current I

Low-Level Output Voltage V

High-Level Output Voltage V
Strobe Output Voltage V

IH

IL

IN

OL

OH

ST

VIN = VDD, Strobe Active, 1, 2 12 – – 100 nA
Pin 12 @ V

V

= V

IN

V

= VST, Strobe Active, 1, 2, 3 12 – – -100 nA

IN

Pin 12 @ V
V

= V

IN

DD

SS

DD

3, 10, 12 12 – – 100 nA

DD

10, 12 12 – – -100 nA
15, 16 12 – – -1.0 µA

V

= V

IN

DD

No Local Smoke, V
No Local Smoke, V

= V

IN

DD

= 17 V 7 12 – – 140 µA

IN

16, 15 9 0.25 – 10 µA

7920–80µA

IO = 10 mA 11 6.5 – – 0.6 V

= 16 mA 8, 9 6.5 – – 1.0 V

I

O

= 5 mA 13 6.5 – 0.5 – V

I

O

IO= -16 mA 8, 9 6.5 5.5 – – V
Inactive IO = -1 µA412
Active, I

= 100 µA to 500 µA4 9

O

VDD - 0.1

VDD - 5.25

––V
–

VDD - 4.75

V

Continued...

5358

PHOTOELECTRIC SMOKE DETECTOR
with INTERCONNECT and TIMER

DC ELECTRICAL CHARACTERISTICS, continued

Test Limits

Characteristic Symbol Test Conditions Pin V

Line Regulation ∆V

ST(∆VDD)

Strobe Temperature Coeff. α

Output Voltage V

I

RED

Line Regulation ∆V

Temperature Coefficient α

I

RED

IRED(∆VDD)

High-Level Output Current I

OFF Leakage Current High I
OFF Leakage Current Low I
Low V

Alarm Threshold V

DD

Common Mode Voltage V
Smoke Comparator Ref. Volt. V

ST

IRED

IRED

OH

OZ

OZ

DD(th)

IC

REF

Active, V
VDD = 6 V to 12 V 4 – – 0.01 – %/°C
Inactive IO = 1 µA, TA = +25°C 6 12 – – 0.1 V
Active I
Active, VDD = 6 V to 12 V 6 – -35 – dB
VDD = 6 V to 12 V 6 – – +0.40 – %/°C
VDD = Alarm, I/O active, 7 9 -4.0 – – mA

V

= VDD - 2 V

O

VO = V
VO = V

Any Alarm Condition 1, 2, 3 ­Any Alarm Condition Internal -

= 6 V to 12 V 4 – – -60 – dB

DD

= -6 mA, TA = +25°C 6 9 2.85 3.1 3.35 V

O

DD

SS

11, 13 12 – – 1.0 µA
11, 13 12 – – -1.0 µA

5 - 6.9 7.2 7.5 V

Min. Typ. Max. Units

DD

VDD - 4

VDD - 3.7

–
–

VDD - 2

VDD - 3.3

V
V

* 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.

AC ELECTRICAL CHARACTERISTICS at T

= -25°C to +75°C*, V

A

(unless otherwise noted).

Test Limits

Characteristic Symbol Test Conditions Pin V

Oscillator Period t
Led Pulse Period t

Led Pulse Width t

osc

led1

t

led4

t

led6

t

led7

w(led)

No Local or Remote Smoke 11 9 39 – 48 s
Remote Smoke Only 11 9 None – – –
Local Smoke or Test 11 9 0.60 0.67 0.74 s
Timer Mode, No Alarm 11 9 9.67 10.8 11.8 s

12 9 9.4 10.5 11.5 ms

11 9 9.5 – 11.5 ms

= 0 V, in typical application

SS

DD

Min. Typ. Max. Units

Continued...

115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 [phone]