Datasheet RE46C190 Datasheet

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Page 1

RE46C190

SOIC

IRED

TEST

TEST2

IRP

IRN

RLED

BST

IRCAP

FEED

GLED

CMOS Low Voltage Photoelectric Smoke Detector ASIC

with Interconnect and Timer Mode

Features

• Two AA Battery Operation

• Internal Power On Reset

• Low Quiescent Current Consumption

• Available in 16L N SOIC

• Local Alarm Memory

• Interconnect up to 40 Detectors

• 9 Minute Timer for Sensitivity Control

• Temporal or Continuous Horn Pattern

• Internal Low Battery and Chamber Test

• All Internal Oscillator

• Internal Infrared Emitter Diode (IRED) driver

• Adjustable IRED Drive current

• Adjustable Hush Sensitivity

• 2% Low Battery Set Point

Description

The RE46C190 is a low power, low voltage CMOS photoelectric type smoke detector IC. With minimal external components, this circuit will provide all the required features for a photoelectric-type smoke detector.

The design incorporates a gain-selectable photo amplifier for use with an infrared emitter/detector pair.

An internal oscillator strobes power to the smoke detection circuitry every 10 seconds, to keep the standby current to a minimum. If smoke is sensed, the detection rate is increased to verify an Alarm condition. A high gain mode is available for push button chamber testing.

A check for a low battery condition is performed every 86 seconds, and chamber integrity is tested once every 43 seconds, when in Standby. The temporal horn pattern supports the NFPA 72 emergency evacuation signal.

An interconnect pin allows multiple detectors to be connected such that, when one unit alarms, all units will sound.

An internal 9 minute timer can be used for a Reduced Sensitivity mode.

Utilizing low power CMOS technology, the RE46C190 was designed for use in smoke detectors that comply with Underwriters Laboratory Specification UL217 and UL268.

PIN CONFIGURATION

 2010 Microchip Technology Inc. DS22271A-page 1

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RE46C190

Control

Logic and

Timing

Trimmed Oscilator

POR and

BIAS

VDD (3)

IRCAP (11)

IRN (7)

IRED (2)

TEST (4)

LX (16)

FEED (10)

HS (14)

BST

(15)

RLED (8)

GLED (9)

HB (13)

IRP (6)

VSS (1)

Interconnect

Programmable

IRED Current

Programmable

Limits

Photo

Integrator

Precision

Reference

TEST2 (5)

Horn Driver

Level

Shift

IO (12)

Current

Sense

Boost Control

Boost Comparator

Low Battery Comparator

Smoke

Comparator

Programming

Control

High

Normal

Hysteresis

TYPICAL BLOCK DIAGRAM

DS22271A-page 2  2010 Microchip Technology Inc.

Page 3

TYPICAL BATTERY APPLICATION

Note 1: C2 should be located as close as possible to the device power pins, and C1 should be located as close

as possible to V

2: R3, R4 and C5 are typical values and may be adjusted to maximize sound pressure. 3: DC-DC converter in High Boost mode (nominal V

BST

= 9.6V) can draw current pulses of greater than 1A, and is therefore very sensitive to series resistance. Critical components of this resistance are the inductor DC resistance, the internal resistance of the battery and the resistance in the connections from the inductor to the battery, from the inductor to the LX pin and from the V

pin to the battery. In order to

function properly under full load at V

= 2V, the total of the inductor and interconnect resistances should not exceed 0.3 . The internal battery resistance should be no more than 0.5  and a low ESR capacitor of 10 µF or more should be connected in parallel with the battery, to average the current draw over the boost converter cycle.

4: Schottky diode D1 must have a maximum peak current rating of at least 1.5A. For best results it should

have forward voltage specification of less than 0.5V at 1A, and low reverse leakage.

5: Inductor L1 must have a maximum peak current rating of at least 1.5A.

IRED

TEST

TEST2

IRP

IRN

RLED

FEED

GLED

IRCAP

BST

RE46C190

4.7 µF

200K

1.5M

1 nF

10 µH

330

33 µF

To other Units

1 µF

100

10 µF

Push-to-Test/

Hush

BST

330

100

RED

GREEN

Smoke

Chamber

Battery

TP1 TP2

BST

100 µF

RE46C190

 2010 Microchip Technology Inc. DS22271A-page 3

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RE46C190

NOTES:

DS22271A-page 4  2010 Microchip Technology Inc.

Page 5

RE46C190

1.0 ELECTRICAL CHARACTERISTICS

Absolute Maximum Ratings†

Supply Voltage.....................................VDD=5.5V; V

Input Voltage Range Except FEED, TEST..... V

FEED Input Voltage Range..................... V

TEST Input Voltage Range ......... V

Input Current except FEED ................................... I

Continuous Operating Current (HS, HB, V

Continuous Operating Current (IRED) ...............I

Operating Temperature ...............................T

Storage Temperature ............................T

ESD Human Body Model.................................. V

ESD Machine Model .............................................V

INTEST

= -.3V to VDD +.3V

=-10 to +22V

INFD

=-.3V to V

)...... IO= 40 mA

BST

OIR

= -10 to +60°C

= -55 to +125°C

STG

HBM

=13V

BST

+.3V

BST

= 10 mA

= 300 mA

= 750V

= 75V

† Notice: Stresses above those listed under “Maximum ratings” may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability.

DC ELECTRICAL CHARACTERISTICS

DC Electrical Characteristics: Unless otherwise indicated, all parameters apply at T

= 4.2V, Typical Application (unless otherwise noted)(Note 1, Note 2, Note 3)

BST

Parameter Symbol

Supply Voltage V

Supply Current I

Standby Boost

DD1

BST1

Test

Min Typ Max Units Conditions

32 —5.0VOperating

3 — 1 2 µA Standby, Inputs low,

15 — 100 — nA Standby, Inputs low,

Current

IRCAP Supply

IRCAP

11 — 500 — µA During smoke check

Current

Boost Voltage V

Input Leakage I

INOP

BST1

BST2

15 3.0 3.6 4.2 V IRCAP charging for Smoke

15 8.5 9.6 10.7 V No local alarm,

6 -200 — 200 pA IRP = VDD or VSS

7 -200 — 200 pA IRN = V

IHF

ILF

Input Voltage Low V

IL1

IL2

Note 1: Wherever a specific V

10 — 20 50 µA FEED = 22V; V

10 -50 -15 — µA FEED = -10V;

10 — — 2.7 V FEED, V

12 — — 800 mV No local alarm,

value is listed under test conditions, the V

BST

inductor disconnected and the DC-DC converter NOT running.

2: Typical values are for design information only. 3: Limits over the specified temperature range are not production tested and are based on characterization

data. Unless otherwise stated, production test is at room temperature with guardbanded limits.

4: Not production tested.

= -10 to +60°C, VDD = 3V,

No loads, Boost Off, No smoke check

Check, GLED operation

=40mA

OUT

RLED Operation,

= 40 mA, IO as an

OUT

input

=10.7V

BST

IO as an input

is forced externally with the

or VSS

BST

= 9V

 2010 Microchip Technology Inc. DS22271A-page 5

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RE46C190

DC ELECTRICAL CHARACTERISTICS (CONTINUED)

DC Electrical Characteristics: Unless otherwise indicated, all parameters apply at T

= 4.2V, Typical Application (unless otherwise noted)(Note 1, Note 2, Note 3)

BST

Parameter Symbol

Input Voltage High V

IO Hysteresis V

Input Pull Down Current

Output Voltage Low V

Output High Voltage V

Output Current I

IODMP

IRED50

IRED100

IRED150

IRED2050

IRED Current

IH1

IH2

HYST1

PD1

PDIO1

PDIO2

OL1

OL2

OL3

OH1

IOH1

IRED

Test

Min Typ Max Units Conditions

10 6.2 — — V FEED; V

12 2.0 — — V No local alarm,

12 — 150 — mV

4, 5 0.25 — 10 µA VIN = V

12 20 — 80 µA VIN = V

12 — — 140 µA VIN = 15V

13, 14 — — 1 V I

8— —300mVI

9— —300mVI

13, 14 8.5 — — V I

12 -4 -5 — mA Alarm, V

12 5 30 — mA At Conclusion of Local

2 45 50 55 mA IRED on, V

2 90 100 110 mA IRED on, V

2 135 150 165 mA IRED on, V

2 180 200 220 mA IRED on, V

— 0.5 — %/°C V Temperature Coefficient

Note 1: Wherever a specific V

value is listed under test conditions, the V

BST

inductor disconnected and the DC-DC converter NOT running.

2: Typical values are for design information only. 3: Limits over the specified temperature range are not production tested and are based on characterization

data. Unless otherwise stated, production test is at room temperature with guardbanded limits.

4: Not production tested.

= -10 to +60°C, VDD = 3V,

BST

IO as an input

= 16 mA, V

= 10 mA, V

= 16 mA, V

= 0V, V

Alarm or Test, V

= 5V, IRCAP = 5V,

BST

(50 mA option selected;

=27°C)

= 5V, IRCAP = 5V,

BST

(100 mA option selected; TA=27°C)

= 5V, IRCAP = 5V,

BST

(150 mA option selected; TA=27°C)

= 5V, IRCAP = 5V,

BST

(200 mA option selected;

=27°C)

= 5V, IRCAP = 5V;

BST

Note 4

is forced externally with the

= 9V

BST

= 3V or

= 9V

BST

= 1V,

IRED

= 1V,

IRED

= 1V,

IRED

= 1V,

IRED

= 9V

= 3.6V

= 9V

=1V

DS22271A-page 6  2010 Microchip Technology Inc.

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RE46C190

DC ELECTRICAL CHARACTERISTICS (CONTINUED)

DC Electrical Characteristics: Unless otherwise indicated, all parameters apply at T

= 4.2V, Typical Application (unless otherwise noted)(Note 1, Note 2, Note 3)

BST

Parameter Symbol

Low Battery Alarm

LB1

Test

Min Typ Max Units Conditions

3 2.05 2.1 2.15 V Falling Edge;

Voltage

Low Battery

LB2

LB3

LB4

LB5

LB6

LB7

LB8

LBHYST

3 2.15 2.2 2.25 V Falling Edge;

3 2.25 2.3 2.35 V Falling Edge;

3 2.35 2.4 2.45 V Falling Edge;

3 2.45 2.5 2.55 V Falling Edge;

3 2.55 2.6 2.65 V Falling Edge;

3 2.65 2.7 2.75 V Falling Edge;

3 2.75 2.8 2.85 V Falling Edge;

3—100—mV

Hysteresis

IRCAP Turn On

TIR1

11 3.6 4.0 4.4 V Falling edge;

Voltage

IRCAP Turn Off

TIR2

11 4.0 4.4 4.8 V Rising edge;

Voltage

Note 1: Wherever a specific V

value is listed under test conditions, the V

BST

inductor disconnected and the DC-DC converter NOT running.

2: Typical values are for design information only. 3: Limits over the specified temperature range are not production tested and are based on characterization

data. Unless otherwise stated, production test is at room temperature with guardbanded limits.

4: Not production tested.

= -10 to +60°C, VDD = 3V,

2.1V nominal selected

2.2V nominal selected

2.3V nominal selected

2.4V nominal selected

2.5V nominal selected

2.6V nominal selected

2.7V nominal selected

2.8V nominal selected

= 5V; I

BST

= 5V; I

BST

is forced externally with the

OUT

= 20 mA

 2010 Microchip Technology Inc. DS22271A-page 7

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RE46C190

AC ELECTRICAL CHARACTERISTICS

AC Electrical Characteristics: Unless otherwise indicated, all parameters apply at T

= 4.2V, Typical Application (unless otherwise noted) (Note 1 to Note 4).

BST

Parameter Symbol Test Pin Min Typ Max Units Condition

Time Base

Internal Clock Period T

PCLK

9.80 10.4 11.0 ms PROGSET,

RLED Indicator

On Time T

Standby Period T

Local Alarm Period T

Hush Timer Period T

External Alarm

ON1

PLED1

PLED2A

PLED2B

PLED4

PLED0

8 9.80 10.4 11.0 ms Operating

8 320 344 368 s Standby, no alarm

8 470 500 530 ms Local alarm condition

8 625 667 710 ms Local alarm condition

8 10 10.7 11.4 s Timer mode, no local

8 LED IS NOT ON s Remote alarm only

Period

GLED Indicator

Latched Alarm Period T

Latched Alarm Pulse

PLED3

OFLED

9 40 43 46 s Latched Alarm Condition,

9 1.25 1.33 1.41 s Latched Alarm Condition,

Train (3x) Off Time

Latched Alarm LED

LALED

9 22.4 23.9 25.3 Hours Latched Alarm Condition,

Enabled Duration

Smoke Check

Smoke Test Period with Temporal Horn Pattern

PER0A

PER1A

PER2A

PER3A

PER4A

2 10 10.7 11.4 s Standby, no alarm

2 1.88 2.0 2.12 s Standby, after one valid

2 0.94 1.0 1.06 s Standby,

2 0.94 1.0 1.06 s Local Alarm

2 235 250 265 ms Push button test,

313 333 353 ms Push button test,

PER5A

2 7.5 8.0 8.5 s In remote alarm

Note 1: See timing diagram for Horn Pattern (Figure 5-2).

2: T

PCLK

and T

are 100% production tested. All other AC parameters are verified by functional testing.

IRON

3: Typical values are for design information only. 4: Limits over the specified temperature range are not production tested, and are based on characterization

data.

= -10° to +60°C, VDD = 3V,

IO = high

with temporal horn pattern

with continuous horn pattern

alarm

LED enabled

smoke sample

after two consecutive valid smoke samples

(three consecutive valid smoke samples)

>1 chamber detections

no chamber detections

DS22271A-page 8  2010 Microchip Technology Inc.

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RE46C190

AC ELECTRICAL CHARACTERISTICS (CONTINUED)

AC Electrical Characteristics: Unless otherwise indicated, all parameters apply at T

= 4.2V, Typical Application (unless otherwise noted) (Note 1 to Note 4).

BST

Parameter Symbol Test Pin Min Typ Max Units Condition

Smoke Test Period with Continuous Horn Pattern

Chamber Test Period T

Long Term Drift

PER0B

PER1B

PER2B

PER3B

PER4B

PER5B

PCT1

LTD

2 10 10.7 11.4 s Standby, no alarm

2 2.5 2.7 2.9 s Standby, after one valid

2 1.25 1.33 1.41 s Standby,

2 1.251.331.41 sLocal Alarm

2 313 333 353 ms Push button test

2 10 10.7 11.4 s In remote alarm

2 40 43 46 s Standby, no alarm

2 400 430 460 s Standby, no alarm

Sample Period

Low Battery

Low Battery Sample Period

PLB1

PLB2

3 320 344 368 s RLED on

3808692 sRLED on

Horn Operation

Low Battery Horn

HPER1

13 40 43 46 s Low battery, no alarm

Period

Chamber Fail Horn

HPER2

13 40 43 46 s Chamber failure

Period

Low Battery Horn

HON1

13 9.8 10.4 11.0 ms Low battery, no alarm

On Time

Chamber Fail Horn

HON2

13 9.8 10.4 11.0 ms Chamber failure

On Time

Chamber Fail

HOF1

13 305 325 345 ms Failed chamber,

Off Time

Alarm On Time

HON2A

13 470 500 530 ms Local or remote alarm with Temporal Horn Pattern

Alarm Off Time

HOF2A

13 470 500 530 ms Local or remote alarm with Temporal Horn Pattern

Alarm On Time

HOF3A

HON2B

13 1.4 1.5 1.6 s Local or remote alarm

13 235 250 265 ms Local or remote alarm with Continuous Horn Pattern

Alarm Off Time

HOF2B

13 78 83 88 ms Local or remote alarm with Continuous Horn Pattern

Note 1: See timing diagram for Horn Pattern (Figure 5-2).

2: T

PCLK

and T

are 100% production tested. All other AC parameters are verified by functional testing.

IRON

3: Typical values are for design information only. 4: Limits over the specified temperature range are not production tested, and are based on characterization

data.

= -10° to +60°C, VDD = 3V,

smoke sample

after two consecutive valid smoke samples

(three consecutive valid smoke samples)

LTD enabled

no alarm, 3x chirp option

(Note 1)

 2010 Microchip Technology Inc. DS22271A-page 9

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RE46C190

AC ELECTRICAL CHARACTERISTICS (CONTINUED)

AC Electrical Characteristics: Unless otherwise indicated, all parameters apply at T

= 4.2V, Typical Application (unless otherwise noted) (Note 1 to Note 4).

BST

Parameter Symbol Test Pin Min Typ Max Units Condition

Push-to-Test Alarm

HON4

13 9.8 10.4 11.0 ms Alarm memory active,

Memory On Time

Push-to-Test Alarm

HPER4

13 235 250 265 ms Alarm memory active,

Memory Horn Period

Interconnect Signal Operation (IO)

IO Active Delay T

Remote Alarm Delay

IODLY1

IODLY2A

12 — 0 — s From start of local alarm

12 0.780 1.00 1.25 s No local alarm, with Temporal Horn Pattern

Remote Alarm Delay

IODLY2B

12 380 572 785 ms No local alarm, with Continuous Horn Pattern

IO Charge

IODMP

12 1.23 1.31 1.39 s At conclusion of local Dump Duration

IO Filter T

IOFILT

12 — — 313 ms Standby, no alarm

Hush Timer Operation

Hush Timer Period T

TPER

8.0 8.6 9.1 Min No alarm

EOL

End-of-Life

EOL

314 334 354 Hours EOL Enabled; Standby

Age Sample

Detection

IRED On Time T

IRON

2 — 100 — µs Prog Bits 3,4 = 1,1 2 — 200 — µs Prog Bits 3,4 = 0,1 2 — 300 — µs Prog Bits 3,4 = 1,0 2 — 400 — µs Prog Bits 3,4 = 0,0

Note 1: See timing diagram for Horn Pattern (Figure 5-2).

2: T

PCLK

and T

are 100% production tested. All other AC parameters are verified by functional testing.

IRON

3: Typical values are for design information only. 4: Limits over the specified temperature range are not production tested, and are based on characterization

data.

= -10° to +60°C, VDD = 3V,

push-to-test

to IO active

from IO active to alarm

alarm or test

TEMPERATURE CHARACTERISTICS

Electrical Specifications: All limits specified for V

Electrical Characteristics.

Parameters Sym Min Typ Max Units Conditions

Temperature Ranges

Operating Temperature Range T

Storage Temperature Range T

Thermal Package Resistances

Thermal Resistance, 16L-SOIC (150 mil.) θ

DS22271A-page 10  2010 Microchip Technology Inc.

STG

=3V, V

= 4.2V and VSS= 0V, Except where noted in the

BST

-10 — +60 °C

-55 — +125 °C

— 86.1 — °C/W

Page 11

2.0 PIN DESCRIPTIONS

The descriptions of the pins are listed in Tab le 2 -1 .

TABLE 2-1: PIN FUNCTION TABLE

RE46C190

SOIC

Symbol Function

RE46C190

2 IRED Provides a regulated and programmable pulsed current for the infrared emitter

4 TEST This input is used to invoke Test modes and the Timer mode. This input has an

5 TEST2 Test input for test and programming modes. This input has an internal pull-down.

6 IRP Connect to the anode of the photo diode.

7 IRN Connect to the cathode of the photo diode.

8 RLED Open drain NMOS output, used to drive a visible LED. This pin provides load current

9 GLED Open drain NMOS output used to drive a visible LED to provide visual indication of

10 FEED Usually connected to the feedback electrode through a current limiting resistor. If not

11 IRCAP Used to charge and monitor the IRED capacitor.

12 IO This bidirectional pin provides the capability to interconnect many detectors in a

13 HB This pin is connected to the metal electrode of a piezoelectric transducer.

14 HS This pin is a complementary output to HB, connected to the ceramic electrode of the

15 V

16 LX Open drain NMOS output, used to drive the boost converter inductor. The inductor

BST

Connect to the negative supply voltage.

diode.

Connect to the positive supply or battery voltage.

internal pull-down.

for the low battery test, and is a visual indicator for Alarm and Hush modes.

an Alarm Memory condition.

used, this pin must be connected to V

single system. This pin has an internal pull-down device and a charge dump device.

piezoelectric transducer.

Boosted voltage produced by DC-DC converter.

should be connected from this pin to the positive supply through a low resistance

path.

or VSS.

 2010 Microchip Technology Inc. DS22271A-page 11

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RE46C190

NOTES:

DS22271A-page 12  2010 Microchip Technology Inc.

Page 13

RE46C190

3.0 DEVICE DESCRIPTION

3.1 St andby Internal Timing

The internal oscillator is trimmed to ±6% tolerance. Once every 10 seconds, the boost converter is powered up, the IRcap is charged from V the detection circuitry is active for 10 ms. Prior to completion of the 10 mS period, the IRED pulse is active for a user-programmable duration of 100400 µs. During this IRED pulse, the photo diode current is integrated and then digitized. The result is compared to a limit value stored in EEPROM during calibration to determine the photo chamber status. If a smoke condition is present, the period to the next detection decreases, and additional checks are made.

3.2 Smoke Detection Circuitry

The digitized photo amplifier integrator output is compared to the stored limit value at the conclusion of the IRED pulse period. The IRED drive is all internal, and both the period and current are user programmable. Three consecutive smoke detections will cause the device to go into Alarm and activate the horn and interconnect circuits. In Alarm, the horn is driven at the high boost voltage level, which is regulated based on an internal voltage reference, and therefore results in consistent audibility over battery life. RLED will turn on for 10 ms at a 2 Hz rate. In Local Alarm, the integration limit is internally decreased to provide alarm hysteresis. The integrator has three separate gain settings:

• Normal and Hysteresis

• Reduced Sensitivity (HUSH)

• High Gain for Chamber Test and Push-to-Test

There are four separate sets of integration limits (all user programmable):

• Normal Detection

• Hysteresis

• HUSH

• Chamber Test and Push-to-Test modes

In addition, there are user selectable integrator gain settings to optimize detection levels (see Tab le 4 -1 ).

and then

BST

3.3 Supervisory Tests

Once every 86 seconds, the status of the battery voltage is checked by enabling the boost converter for 10 ms and comparing a fraction of the V an internal reference. In each period of 344 seconds, the battery voltage is checked four times. Three checks are unloaded and one check is performed with the RLED enabled, which provides a battery load. The High Boost mode is active only for the loaded low battery test. In addition, once every 43 seconds the chamber is activated and a High Gain mode and chamber test limits are internally selected. A check of the chamber is made by amplifying background reflections. The Low Boost mode is used for the chamber test.

If either the low battery test or the chamber test fails, the horn will pulse on for 10 ms every 43 seconds, and will continue to pulse until the failing condition passes. If two consecutive chamber tests fail, the horn will pulse on three times for 10 ms, separated by 330 ms every 43 seconds. Each of the two supervisory test audible indicators is separated by approximately 20 seconds.

As an option, a Low Battery Silence mode can be invoked. If a low battery condition exists, and the TEST input is driven high, the RLED will turn on. If the TEST input is held for more than 0.5 second, the unit will enter the Push-to-test operation described in

Section 3.4 “Push-to-Test Operation (PTT)”. After

the TEST input is driven low, the unit enters in Low Battery Hush mode, and the 10 ms horn pulse is silenced for 8 hours. The activation of the test button will also initiate the 9 minute Reduced Sensitivity mode

described in Section 3.6 “Reduced Sensitivity

Mode”. At the end of the 8 hours, the audible indication

will resume if the low battery condition still exists.

voltage to

3.4 Push-to-Test Operation (PTT)

If the TEST input pin is activated (VIH), the smoke detection rate increases to once every 250 ms after one internal clock cycle. In Push-to-Test, the photo amplifier High Gain mode is selected, and background reflections are used to simulate a smoke condition. After the required three consecutive detections, the device will go into a Local Alarm condition. When the TEST input is driven low (V Normal Gain is selected, after one clock cycle. The detection rate continues at once every 250 ms until three consecutive No Smoke conditions are detected. At this point, the device returns to standby timing. In addition, after the TEST input goes low, the device

enters the HUSH mode (see Section 3.6 “Reduced

Sensitivity Mode”).

), the photo amplifier

 2010 Microchip Technology Inc. DS22271A-page 13

Page 14

RE46C190

3.5 Interconnect Operation

The bidirectional IO pin allows the interconnection of multiple detectors. In a Local Alarm condition, this pin is driven high (High Boost) immediately through a constant current source. Shorting this output to ground will not cause excessive current. The IO is ignored as input during a Local Alarm.

The IO pin also has an NMOS discharge device that is active for 1.3 seconds after the conclusion of any type of Local Alarm. This device helps to quickly discharge any capacitance associated with the interconnect line.

If a remote, active high signal is detected, the device goes into Remote Alarm and the horn will be active. RLED will be off, indicating a Remote Alarm condition. Internal protection circuitry allows the signaling unit to have a higher supply voltage than the signaled unit, without excessive current draw.

The interconnect input has a 336 ms nominal digital filter. This allows the interconnection to other types of alarms (carbon monoxide, for example) that may have a pulsed interconnect signal.

3.6 Reduc ed S e n s itivity Mode

A Reduced Sensitivity or Hush mode is initiated by activating the TEST input (V activated during a Local Alarm, the unit is immediately reset out of the alarm condition, and the horn is silenced. When the TEST input is deactivated (V device enters into a 9-minute nominal Hush mode. During this period, the HUSH integration limit is selected. The hush gain is user programmable. In Reduced Sensitivity mode, the RLED flashes for 10 ms every 10 seconds to indicate that the mode is active. As an option, the Hush mode will be cancelled if any of the following conditions exist:

• Reduced sensitivity threshold is exceeded (high smoke level)

• An interconnect alarm occurs

• TEST input is activated again

). If the TEST input is

), the

3.7 Local Alarm Memory

An Alarm Memory feature allows easy identification of any unit that had previously been in a Local Alarm condition. If a detector has entered a Local Alarm, when it exits that Local Alarm, the Alarm Memory latch is set. Initially the GLED can be used to visually identify any unit that had previously been in a Local Alarm condition. The GLED flashes three times spaced

1.3 seconds apart. This pattern will repeat every 43 seconds. The duration of the flash is 10 ms. In order to preserve battery power, this visual indication will stop after a period of 24 hours. The user will still be able to identify a unit with an active alarm memory by pressing the Push-to-Test button. When this button is active, the horn will chirp for 10 ms every 250 ms.

If the Alarm Memory condition is set, then any time the Push-to-Test button is pressed and released, the Alarm Memory latch is reset.

The initial 24 hour visual indication is not displayed if a low battery condition exists.

3.8 End of Life Indicator

As an option, after every 14 days of continuous operation, the device will read a stored age count from the EEPROM and increment this count. After 10 years of powered operation, an audible warning will occur indicating that the unit should be replaced. This indicator will be similar to the chamber test failure warning in that the horn will pulse on three times for 10 ms separated by 330 ms every 43 seconds. This indicator will be separated from the low battery indicator by approximately 20 seconds.

3.9 Photo Chamber Long Term Drift Adjustment

As an option, the design includes a Long Term Drift Adjustment for the photo chamber. If this option is selected, during calibration a normal no-smoke baseline integration measurement is made and stored in EEPROM. During normal operation, a new baseline is calculated by making 64 integration measurements over a period of 8 hours. These measurements are averaged and compared to the original baseline stored during calibration to calculate the long term drift. All four limits stored during calibration are adjusted by this drift factor. Drift sampling is suspended during Hush, Local Smoke and Remote Smoke conditions.

DS22271A-page 14  2010 Microchip Technology Inc.

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4.0 USER PROGRAMMING MODES

TABLE 4-1: PARAMETRIC PROGRAMMING

Parametric Programming Range Resolution

IRED Period 100-400 µs 100 µs

IRED Current Sink 50-200 mA 50 mA

Low Battery Detection Voltage 2.1 – 2.8V 100 mV

Photo Detection Limits Typical Maximum Input Current (nA)

100 µs 200 µs 300 µs 400 µs

Normal/Hysteresis GF = 1 58 29 19.4 14.5

GF = 2 29 14.5 9.6 7.2

GF = 3 14.5 7.2 4.8 3.6

GF = 4 7.2 3.6 2.4 1.8

Hush GF = 1 116 58 38.8 29

GF = 2 58 29 19.4 14.5

GF = 3 29 14.5 9.6 7.2

GF = 4 14.5 7.2 4.8 3.6

Chamber Test GF = 1 29 14.5 9.6 7.2

GF = 2 14.5 7.2 4.8 3.6

GF = 3 7.2 3.6 2.4 1.8

GF = 4 3.6 1.8 1.2 0.9

Note 1: GF is the user selectable Photo Integration Gain Factor. Once selected, it applies to all modes of

operation. For example, if GF = 1 and integration time is selected to be 100 µs, the ranges will be as follows: Normal/Hysteresis = 58 nA, Hush = 116 nA, Chamber Test = 29 nA.

2: Nominal measurement resolution in each case will be 1/31 of the maximum input range. 3: The same current resolution and ranges applies to the limits.

TABLE 4-2: FEATURES PROGRAMMING

Features Options

Tone Select Continuous or NFPA Tone

10 Year End-of-life Indicator Enable/Disable

Photo Chamber Long Term Drift Adjustment Enable/Disable

Low Battery Hush Enable/Disable

Hush Options Option 1: Hush mode is not cancelled for any reason. If the

test button is pushed during Hush, the unit reverts to Normal Sensitivity to test the unit, but when it comes out of test, resumes in Hush where it left off.

Option 2: The Hush mode is cancelled if the Reduced Sensitivity threshold is exceeded (high smoke level), and if an external (interconnect alarm) is signaled. If the test button is pushed during Hush, after the test is executed, the Hush mode is terminated.

 2010 Microchip Technology Inc. DS22271A-page 15

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RE46C190

4.1 Calibration and Programming Procedures

Eleven separate programming and test modes are available for user customization. To enter these modes, after power-up, TEST2 must be driven to VDD and held at that level. The TEST input is then clocked to step through the modes. FEED and IO are reconfigured to become test mode inputs, while RLED, GLED and HB become test mode outputs. The test mode functions for

When TEST2 is held at VDD, TEST becomes a tri-state input with nominal input levels at V

, VDD and V

TEST clock occurs whenever the TEST input switches from VSS to V

. The TEST Data column represents

BST

the state of TEST when used as a data input, which would be either VSS or VDD. The TEST pin can therefore be used as both a clock, to change modes, and a data input, once a mode is set. Other pin

functions are described in Section 4.2 “User

Selections”.

each pin are outlined in Table 4-3.

TABLE 4-3: TEST MODE FUNCTIONS

TEST Clock

BST

Mode

Description

T0 Photo Gain Factor

(2 bits)

Integ Time (2 bits) 0 ProgData V

IRED Current (2 bits) 0 ProgData V

Low Battery Trip (3 bits)

LTD Enable (1 bit) 0 ProgData V

Hush Option (1 bit) 0 ProgData V

LB Hush Enable (1 bit)

EOL Enable (1 bit) 0 ProgData V

Tone Select (1 bit) 0 ProgData V

T1 Norm Lim Set

T2 Hyst Lim Set

T3 Hush Lim Set

T4 Ch Test Lim Set

(5 bits)

(4)

T5 LTD Baseline (5 bits) 5 not used V

T6 Serial Read/Write 6 ProgData V

T7 Norm Lim Check 7 not used V

T8 Hyst Lim Check 8 not used V

T9 Hush Lim Check 9 not used V

T10 Ch Test Lim Check 10 not used V

T11 Horn Test 11 not used V

Note 1: SmkComp (HB) – digital comparator output (high if Gamp < IntegOut; low if Gamp > IntegOut)

2: SCMP (HB) – digital output representing comparison of measurement value and associated limit. Signal is

valid only after MeasEn has been asserted and measurement has been made. (SCMP high if measured value > limit; low if measured value < limit).

3: LatchLim (IO) – digital input used to latch present state of limits (Gamp level) for later storage. T1-T4 limits

are latched, but not stored until ProgEn is asserted in T5 mode.

4: Operating the circuit in this manner with nearly continuous IRED current for an extended period of time

may result in undesired or excessive heating of the part. The duration of this step should be minimized.

TEST

Data

TEST2 FEED IO RLED GLED HB

0 ProgData V

1 not used V

2 not used V

3 not used V

4 not used V

BST

—— —

ProgCLK ProgEn 14 bits RLED GLED HB

CalCLK LatchLim

(3)

Gamp IntegOut SmkComp

(3)

Gamp IntegOut SmkComp

(3)

Gamp IntegOut SmkComp

(3)

Gamp IntegOut SmkComp

MeasEn ProgEn 25 bits Gamp IntegOut SmkComp

ProgCLK ProgEn RLED GLED Serial Out

MeasEn not used Gamp IntegOut SCMP

FEED HornEn RLED GLED HB

BST

(2) (2) (2) (2)

. A

(1)

DS22271A-page 16  2010 Microchip Technology Inc.

Page 17

4.2 User Selections

IRED

TEST

TEST2

IRP

IRN

RLED

FEED

GLED

IRCAP

BST

RE46C190

V4 V5 V6

Smoke Chamber

Monitor RLED, GLED, and HB

Prior to smoke calibration, the user must program the functional options and parametric selections. This requires that 14 bits, representing selected values, be clocked in serially using TEST as a data input and FEED as a clock input, and then be stored in the internal EEPROM.

The detailed steps are as follows:

1. Power up with bias conditions as shown in

Figure 4-1. At power-up

TEST = TEST2 = FEED = IO = V

RE46C190

FIGURE 4-1: Nominal Application Circuit for Programming.

 2010 Microchip Technology Inc. DS22271A-page 17

Page 18

RE46C190

2. Drive TEST2 input from VSS to VDD and hold at through Step 5 below.

3. Using TEST as data and FEED as clock, shift in

values as selected from Register 4-1.

W-x W-x W-x W-x W-x W-x W-x

TS EOL LBH HUSH LTD LB0 LB1

bit 38 bit 32

W-x W-x W-x W-x W-x W-x W-x W-x

LB2 IRC1 IRC0 IT1 IT0 PAGF1 PAGF0 NL4

bit 31 bit 24

W-x W-x W-x W-x W-x W-x W-x W-x

NL3 NL2 NL1 NL0 HYL4 HYL3 HYL2 HYL1

bit 23 bit 16

W-x W-x W-x W-x W-x W-x W-x W-x

HYL0 HUL4 HUL3 HUL2 HUL1 HUL0 CTL4 CTL3

bit 15 bit 8

Note: For test mode T0 only 14 bits (bits 25-38)

will be loaded. For test mode T6 all 39 bits (bits 0-38), will be loaded.

W-x W-x W-x W-x W-x W-x W-x W-x

CTL2 CTL1 CTL0 LTD4 LTD3 LTD2 LTD1 LTD0

bit 7 bit 0

Legend:

R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’

-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown

bit 38 TS: Tone Select bit

1 = Temporal Horn Pattern 0 = Continuous Horn Pattern

bit 37 EOL: End of Life Enable bit

1 = Enable 0 = Disable

bit 36 LBH: Low Battery Hush Enable bit

1 = Enable 0 = Disable

bit 35 HUSH: Hush Option bit

1 = Cancelled for high smoke level, interconnect alarm, or second push of TEST button

(as described above)

0 = Never Cancel

bit 34 LTD: Long Term Drift Enable bit

1 = Enable 0 = Disable

DS22271A-page 18  2010 Microchip Technology Inc.

Page 19

RE46C190

bit 33-31 LB<0:2>: Low Battery Trip Point bits

000 = 2.1V 001 = 2.5V 010 = 2.3V 011 = 2.7V 100 = 2.2V 101 = 2.6V 110 = 2.4V 111 = 2.8V

bit 30-29 IRC<1:0>: IRED Current bits

00 =50mA 01 =100mA 10 =150mA 11 =200mA

bit 28-27 IT<1:0>: Integration Time bits

00 =400µs 01 =300µs 10 =200µs 11 =100µs

bit 26-25 PAGF<1:0>: Photo Amplifier Gain Factor bits

00 =1 01 =2 10 =3 11 =4

bit 24-20 NL<4:0>: Normal Limits bits (Section 3.2)

00000 =0 00001 =1

•

11110 =30 11111 =31

bit 19-15 HYL<4:0>: Hysteresis Limits bits (Section 3.2)

00000 =0 00001 =1

•

11110 =30 11111 =31

bit 14-10 HUL<4:0>: Hush Limits bits (Section 3.6)

00000 =0 00001 =1

•

11110 =30 11111 =31

 2010 Microchip Technology Inc. DS22271A-page 19

Page 20

RE46C190

TEST2

TEST bit 25 bit 26 bit 27 bit 28 bit 29 bit 30 bit 31 bit 32 bit 33 bit 34 bit 35 bit 36 bit 37 bit 38

BST

FEED

Min Tsetup2 = 2 µs Min Tsetup1 = 1 µs Min Thold1 = 1 µs Min PW1 = 10us Min T1 = 20 µs Min Td1 = 2 µs

IO …

Min PW2 = 10 ms

bit 9-5 CTL<4:0>: Chamber Test Limits bits (Section 3.3)

00000 =0 00001 =1

•

11110 =30 11111 =31

bit 4-0 LTD<4:0>: Long Term Drift Sample bits (Section 3.9)

00000 =0 00001 =1

•

11110 =30 11111 =31

The minimum pulse width for FEED is 10 µs, while the minimum pulse width for TEST is 100 µs. For example, for the following options, the sequence would be:

data - 0 0 0 1 1 0 0 0 1 0 0 0 0 1

bit - 25 26 27 28 29 30 31 32 33 34 35 36 37 38

Photo Amp Gain Factor = 1

Integration Time = 200 µs

IRED Current = 100 mA

Low Battery Trip = 2.2V

Long Term Drift, Low Battery Hush and EOL are all disabled

Hush Option = Never Cancel

Tone Select = Temporal

4. After shifting in data, pull IO input to V (minimum pulse width of 10 ms) to store

, then

shift register contents into the memory.

5. If any changes are required, power down the

part and return to Step 1. All bit values must be reentered.

FIGURE 4-2: Timing Diagram for Mode T0.

DS22271A-page 20  2010 Microchip Technology Inc.

Page 21

As an alternative to Figure 4-1, Figure 4-3 can be used

330

BST

IRED

TEST

TEST2

IRP

IRN

RLED

FEED

GLED

IRCAP

BST

RE46C190

4.7 µF

200K

1.5M

1 nF

10 µH

330

33 µF

To other Units

1 µF

100

10 µF

BST

100

RED

GREEN

100 µF

Smoke Chamber

TP1

TP2

V5 V6 V7

Monitor RLED,

GLED and HB

Push-To-Test/

Hush

to program while in the application circuit. Note that in addition to the five programming supplies, connections

are needed at TP1 and TP2.

to V

RE46C190

FIGURE 4-3: Circuit for Programming in the Typical Application.

 2010 Microchip Technology Inc. DS22271A-page 21

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4.3 Smoke Calibration

A separate calibration mode is entered for each measurement mode (Normal, Hysteresis, Hush and Chamber Test) so that independent limits can be set for each. In all calibration modes, the integrator output can be accessed at the GLED output.

The Gamp output voltage, which represents the smoke detection level, can be accessed at the RLED output. The SmkComp output voltage is the result of the comparison of Gamp with the integrator output, and can be accessed at HB. The FEED input can be clocked to step up the smoke detection level at RLED. Once the desired smoke threshold is reached, the TEST input is pulsed low to high to store the result.

The procedure is described in the following steps:

1. Power up with the bias conditions shown in

Figure 4-1.

2. Drive TEST2 input from V Programming mode. TEST2 should remain at VDD through Step 8 described below.

3. Apply a clock pulse to the TEST input to enter in T1 mode. This initiates the calibration mode for Normal Limits setting. The Integrator output saw tooth should appear at GLED and the smoke detection level at RLED. Clock FEED to increase the smoke detection level as needed. Once the desired smoke threshold is reached, the IO input is pulsed low to high to enter the result. See typical waveforms in Figure 4-4. Operating the circuit in this manner, with nearly continuous IRED current for an extended period of time, may result in undesired or excessive heating of the part. The duration of this step should be minimized.

4. Apply a second clock pulse to the TEST input to enter in T2 mode. This initiates the calibration mode for Hysteresis Limits. Clock FEED as in

Step 3 and apply pulse to IO, once desired level

is reached.Operating the circuit in this manner, with nearly continuous IRED current for an extended period of time, may result in undesired or excessive heating of the part. The duration of this step should be minimized.

to VDD to enter the

5. Apply a clock pulse to the TEST input again to enter in T3 mode and initiate calibration for Hush Limits. Clock FEED as in the steps above and apply a pulse to IO, once the desired level is reached. Operating the circuit in this manner, with nearly continuous IRED current for an extended period of time, may result in undesired or excessive heating of the part. The duration of this step should be minimized.

6. Apply a clock pulse to the TEST input a fourth time to enter in T4 mode, and initiate the calibration for Chamber Test Limits. Clock FEED and apply pulse to IO, once desired level is reached. Operating the circuit in this manner, with nearly continuous IRED current for an extended period of time, may result in undesired or excessive heating of the part. The duration of this step should be minimized.

7. If the Long Term Drift Adjustment is enabled, after all limits have been set, the long term drift (LTD) baseline measurement must be made. To do this, a measurement must be made under no-smoke conditions. To enable the baseline measurement, pull TEST from V again and return to VSS. Once the chamber is clear, pulse FEED low to high to make the baseline measurement.

8. After limits have been set and baseline LTD measurement has been made, pulse IO to store all results in memory. Before this step, no limits are stored in memory.

to V

BST

DS22271A-page 22  2010 Microchip Technology Inc.

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RE46C190

TEST2

Min Tsetup2 = 2 µs

BST

TEST

Min PW3 = 100 µs

BST

FEED

Min Td2 = 10 µ

Min PW1 = 10 µs Min T1 = 20 µ

Min PW5 = 2 ms

Min PW2 = 10 ms

GLED … … … …

IRED … … … …

RLED

FIGURE 4-4: Timing Diagram for Modes T1 to T5.

 2010 Microchip Technology Inc. DS22271A-page 23

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RE46C190

TEST2

BST

TEST D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D15 … D39

Min Tsetup2 = 2 µs Min PW3 = 100 µs Min T2 = 120 µs

BST

FEED …

Min Tsetup1 = 1 µs Min Thold1 = 1 µs Min PW1 = 10 µs Min T1 = 20 µs

IO …

Min PW2 = 10 ms

4.4 Serial Read/Write

As an alternative to the steps in Section 4 .3 “Smoke

Calibration”

characterized, the limits and baseline can be entered directly from a serial read/write calibration mode.

To enter this mode, follow these steps:

1. Set up the application as shown in Figure 4-1.

2. Drive TEST2 input from V Programming mode. TEST2 should remain at VDD until all data has been entered.

3. Clock the TEST input to mode T6 (High = V Low = V read/write mode.

4. TEST now acts as a data input (High = V Low = V (High = V LTD baseline, functional and parametric options. The data sequence should be as follows:

5 bit LTD sample (LSB first)

5 bit Chamber Test Limits (LSB first)

5 bit Hush Limits (LSB first)

5 bit Hysteresis Limits (LSB first),

, if the system has been well

to VDD to enter in

, 6 clocks). This enables the serial

). FEED acts as the clock input

, Low = VSS). Clock in the limits,

BST

5 bit Normal Limits (LSB first)

Then, the data sequence follows the pattern described in Register 4-1:

2 bit Photo Amp Gain Factor

2 bit Integration Time

2 bit IRED current

3 bit Low Battery Trip Point

1 bit Long Term Drift Enable

1 bit Hush Option

1 bit Low Battery Hush Enable

1 bit EOL enable

1 bit Tone Select

A serial data output is available at HB.

5. After all 39 bits have been entered, pulse IO to store into the EEPROM memory.

FIGURE 4-5: Timing Diagram for Mode T6.

DS22271A-page 24  2010 Microchip Technology Inc.

Page 25

RE46C190

TEST2

BST

TEST

Min Tsetup2 = 2 µs Min PW3 = 100 µs Min T2 = 120 µs

Vbst

FEED

GLED ………

IRED ………

RLED

4.5 Limits Verification

After all limits and LTD baseline have been entered and stored into the memory, additional test modes are available to verify if the limits are functioning as expected. Ta bl e 4 -4 describes several verification tests.

TABLE 4-4: LIMITS VERIFICATION DESCRIPTION

Limit Test Description

Normal Limits Clock TEST to Mode T7 (7 clocks). With appropriate smoke level in chamber, pull FEED to

and hold for at least 1 ms. The HB output will indicate the detection status

(High = smoke detected).

Hysteresis Limits Clock TEST to Mode T8 (8 clocks). Pulse FEED and monitor HB as in Normal Limits case.

Hush Limits Clock TEST to Mode T9 (9 clocks). Pulse FEED and monitor HB.

Chamber Test Limits Clock TEST to Mode T10 (10 clocks). Pulse FEED and monitor HB.

Min Td2 = 10 µs Min PW5 = 2 ms

FIGURE 4-6: Timing Diagram for Modes T7-T10.

 2010 Microchip Technology Inc. DS22271A-page 25

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RE46C190

TEST2

BST

TEST

Min Tsetup2 = 2 µs Min PW3 = 100 µs Min T2 = 120 µs

4.6 Horn Test

The last test mode allows the horn to be enabled indefinitely for audibility testing. To enter this mode, clock TEST to Mode T11 (11 clocks). The IO pin is configured as horn enable.

FIGURE 4-7: Timing Diagram for Mode T11.

Horn Enabled

DS22271A-page 26  2010 Microchip Technology Inc.

Page 27

RE46C190

3.6V 0.1A 200s



43s 0.85 3V



---------------------------------------------------0.657A=

5.0 APPLICATION NOTES

5.1 Standby Current Calculation and Battery Life

The supply current shown in the DC Electrical

Characteristics

average standby current and, in most cases, can be a small fraction of the total, because power consumption generally occurs in relatively infrequent bursts and depends on many external factors. These include the values selected for IRED current and integration time, the V

and IR capacitor sizes and leakages, the V

BST

level, and the magnitude of any external resistances that will adversely affect the boost converter efficiency.

TABLE 5-1: STANDBY CURRENT CALCULATION

IDD Component

Fixed I

Photo Detection Current

(excluding IR drive)

Smoke Detection

(excluding IR drive)

Smoke Detection

Low Battery Check Current

The following paragraphs explain the components in

Table 5-1, and the calculations in the example.

5.1.1 FIXED IDD

The I

Electrical Characteristics

is the Supply Current shown in the DC

5.1.2 PHOTO DETECTION CURRENT

Photo Detection Current is the current draw due to the smoke testing every 10.75 seconds, and the chamber test every 43 seconds. The current for both the IR diode and the internal measurement circuitry comes primarily from V scaled for both on-time and boost voltage.

table is only one component of the

Voltage

Current

(V)

3 1.00E-06 — — — 3.00E-06 1.00E-06 1.0

Chamber test

IR drive during

3.6 1.00E-03 1.00E-02 3.60E-05 43 9.85E-07 3.28E-07 0.3

3.6 0.10 2.00E-04 7.20E-05 43 1.97E-06 6.57E-07 0.7

Chamber Test

3.6 1.00E-03 1.00E-02 3.60E-05 10.75 3.94E-06 1.31E-06 1.3

IR drive during

3.6 0.10 2.00E-04 7.20E-05 10.75 7.88E-06 2.63E-06 2.6

Loaded Test

Load 9 2.00E-02 1.00E-02 1.80E-03 344 6.16E-06 2.05E-06 2.1

Boost V

to V

BST1

BST2

Unloaded Test

Load 3.6 1.00E-04 1.00E-02 3.60E-06 43 9.85E-08 3.28E-08 0.0

table.

, so the average current must be

BST

BAT

Duration

(A)

(s)

— — 6.85E-05 344 2.34E-07 7.81E-08 0.1

A calculation of the standby current for the battery life is shown in Ta b l e 5 - 1 , based on the following parameters:

BAT

=3.6

BST1

BST2

Boost capacitor size = 4.70E-06

Boost Efficiency = 8.50E-01

IRED on time = 2.000E-04

IRED Current = 1.000E-01

Energy

(J)

Period

(s)

Average

Power

(W)

Contribution

BAT

(A)

BAT

(µA)

Total 8.09E-06 8.1

The contribution to I

is determined by first

BAT

calculating the energy consumed by each component, given its duration. An average power is then calculated based on the period of the event and the boost converter efficiency (assumed to be 85% in this case). An I average power and the given V

contribution is then calculated based on this

BAT

. For example, the IR

BAT

drive contribution during chamber test is detailed in

Equation 5-1:

EQUATION 5-1:

 2010 Microchip Technology Inc. DS22271A-page 27

Page 28

RE46C190

5.1.3 LOW BATTERY CHECK CURRENT

The Low Battery Check Current is the current required for the low battery test. It includes both the loaded (RLED on) and unloaded (RLED Off) tests. The boost component of the loaded test represents the cost of charging the boost capacitor to the higher voltage level. This has a fixed cost for every loaded check, because the capacitor is gradually discharged during subsequent operations, and the energy is generally not recovered. The other calculations are similar to those shown in Equation 5-1. The unloaded test has a minimal contribution because it involves only some internal reference and comparator circuitry.

5.1.4 BATTERY LIFE

When estimating the battery life, several additional factors must be considered. These include battery resistance, battery self discharge rate, capacitor leakages and the effect of the operating temperature on all of these characteristics. Some number of false alarms and user tests should also be included in any calculation.

For ten year applications, a 3V spiral wound lithium manganese dioxide battery with a laser seal is recommended. These can be found with capacities of 1400 to 1600 mAh.

DS22271A-page 28  2010 Microchip Technology Inc.

Page 29

5.1.5 FUNCTIONAL TIMING DIAGRAMS

Standby, No Alarm (not to Scale)

IRON

PER0

IRED

Chambe r Test (Internal Signal)

PCT1

Low Battery Test (Internal signal)

PLB2

ON1

RLED

PLB1

LTD S ample

LTD

EOL

Low Suppl y Test Failure

Low Battery Test (Internal signal)

RLED

HON1

HORN

HPER1

Chamber Test Failure

Chambe r Test (Internal Signal)

HORN

HOF2

HPER2

RE46C190

FIGURE 5-1: RE46C190 Timing Diagram – Standby, No Alarm, Low Supply Test Failure and

HON2

Chamber Test Failure.

 2010 Microchip Technology Inc. DS22271A-page 29

Page 30

RE46C190

Local Alarm with Tempor al Horn Pattern (not to Scale)

IRON

IRED

PER 3A

ON1

RLED

PLED 2A

HON2A

HOF2A

HOF3A

HORN

IODL Y1

IO a s Outp ut

IRO N

IRED

PER3B

RLED

PLED2B

HORN

IO a s Outp ut

Interconn ec t as Input with Te m poral Horn patte rn (not to Scale)

IO a s Input

IODL YA

HORN

Interconnect as Input with International Horn Pattern (not to Scale)

IOFIL T

IO a s Input

IODL YB

No Ala rm L ocal Ala rm

ON1

Local Alarm with Internation al Horn Pattern (not to Scale)

IODL Y1

FIGURE 5-2: RE46C190 Timing Diagram – Local Alarm with Temporal Horn Pattern, Local Alarm

IOFIL T

HON2B

HOF2B

with International Horn Pattern, Interconnect as Input with Temporal Horn Pattern and Interconnect as Input with International Horn Pattern.

DS22271A-page 30  2010 Microchip Technology Inc.

Page 31

RE46C190

Alarm Memory (not to Scale)

Alarm Memory

Alarm, No Low B attery Alar m Memory; N o Alarm; No Low Batt ery Al arm M emory After 24 Hour Ti mer Indicat ion

RLED

GLED

TEST

Hush Timer (not to Scale)

Alarm, No Low B attery Time r Mode ; No Alar m; No Low Battery Standb y, No Alar m

RLED

TEST

PLED1

ON1

PLED2

ON1

OFLED

PLED1

LALED

PLED1

HON 4

HPER4

ON1

PLED2

PLED4

TPER

FIGURE 5-3: RE4 6C1 90 Timing Dia gram – Alar m Mem ory and Hus h Timer.

 2010 Microchip Technology Inc. DS22271A-page 31

PLED1

Page 32

RE46C190

NOTES:

DS22271A-page 32  2010 Microchip Technology Inc.

Page 33

6.0 PACKAGING INFORMATION

Legend: XX...X Customer-specific information

Y Year code (last digit of calendar year) YY Year code (last 2 digits of calendar year) WW Week code (week of January 1 is week ‘01’) NNN Alphanumeric traceability code Pb-free JEDEC designator for Matte Tin (Sn)

* This package is Pb-free. The Pb-free JEDEC designator ( )

can be found on the outer packaging for this package.

Note: In the event the full Microchip part number cannot be marked on one line, it will

be carried over to the next line, thus limiting the number of available characters for customer-specific information.

16-Lead SOIC (.150”)

XXXXXXXXXXXXX XXXXXXXXXXXXX

YYWWNNN

Example

RE46C190

1035256

V/SL

6.1 Package Marking Information

RE46C190

 2010 Microchip Technology Inc. DS22271A-page 33

Page 34

RE46C190

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1RWHV

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6WDQGRII $  ± 

2YHUDOO:LGWK ( %6&

0ROGHG3DFNDJH:LGWK ( %6&

2YHUDOO/HQJWK ' %6&

&KDPIHURSWLRQDO K  ± 

)RRW/HQJWK /  ± 

)RRWSULQW / 5()

)RRW$QJOH   ± 

/HDG7KLFNQHVV F  ± 

/HDG:LGWK E  ± 

0ROG'UDIW$QJOH7RS   ± 

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NOTE 1

0LFURFKLS 7HFKQRORJ\ 'UDZLQJ &%

DS22271A-page 34  2010 Microchip Technology Inc.

Page 35

Note: For the most current package drawings, please see the Microchip Packaging Specification located at

http://www.microchip.com/packaging

RE46C190

 2010 Microchip Technology Inc. DS22271A-page 35

Page 36

RE46C190

NOTES:

DS22271A-page 36  2010 Microchip Technology Inc.

Page 37

APPENDIX A: REVISION HISTORY

Revision A (December 2010)

• Original Release of this Document.

RE46C190

 2010 Microchip Technology Inc. DS22271A-page 37

Page 38

RE46C190

NOTES:

DS22271A-page 38  2010 Microchip Technology Inc.

Page 39

PRODUCT IDENTIFICATION SYSTEM

Device RE46C190: CMOS Photoelectric Smoke Detector ASIC

RE46C190T: CMOS Photoelectric Smoke Detector ASIC

(Tape and Reel)

Package S = Small Plastic Outline - Narrow, 3.90 mm Body,

16-Lead (SOIC)

Examples:

a) RE46C190S16F: 16LD SOIC Package,

Lead Free

b) RE46C190S16TF: 16LD SOIC Package,

Tape and Reel, Lead Free

PART NO. X

Package

Device

Number of Pins

Tape and Reel Free

Lead

To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.

RE46C190

 2010 Microchip Technology Inc. DS22271A-page 39

Page 40

RE46C190

NOTES:

DS22271A-page 40  2010 Microchip Technology Inc.

Page 41

Note the following details of the code protection feature on Microchip devices:

• Microchip products meet the specification contained in their particular Microchip Data Sheet.

• Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the intended manner and under normal conditions.

• There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data Sheets. Most likely, the person doing so is engaged in theft of intellectual property.

• Microchip is willing to work with the customer who is concerned about the integrity of their code.

• Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not mean that we are guaranteeing the product as “unbreakable.”

Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.

Information contained in this publication regarding device applications and the like is provided only for your convenience and may be superseded by updates. It is your responsibility to ensure that your application meets with your specifications. MICROCHIP MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND WHETHER EXPRESS OR IMPLIED, WRITTEN OR ORAL, STATUTORY OR OTHERWISE, RELATED TO THE INFORMATION, INCLUDING BUT NOT LIMITED TO ITS CONDITION, QUALITY, PERFORMANCE, MERCHANTABILITY OR FITNESS FOR PURPOSE

. Microchip disclaims all liability

arising from this information and its use. Use of Microchip devices in life support and/or safety applications is entirely at the buyer’s risk, and the buyer agrees to defend, indemnify and hold harmless Microchip from any and all damages, claims, suits, or expenses resulting from such use. No licenses are conveyed, implicitly or otherwise, under any Microchip intellectual property rights.

Trademarks

The Microchip name and logo, the Microchip logo, dsPIC,

EELOQ, KEELOQ logo, MPLAB, PIC, PICmicro, PICSTART,

logo, rfPIC and UNI/O are registered trademarks of

PIC Microchip Technology Incorporated in the U.S.A. and other countries.

FilterLab, Hampshire, HI-TECH C, Linear Active Thermistor, MXDEV, MXLAB, SEEVAL and The Embedded Control Solutions Company are registered trademarks of Microchip Technology Incorporated in the U.S.A.

Analog-for-the-Digital Age, Application Maestro, CodeGuard, dsPICDEM, dsPICDEM.net, dsPICworks, dsSPEAK, ECAN, ECONOMONITOR, FanSense, HI-TIDE, In-Circuit Serial Programming, ICSP, Mindi, MiWi, MPASM, MPLAB Certified logo, MPLIB, MPLINK, mTouch, Omniscient Code Generation, PICC, PICC-18, PICDEM, PICDEM.net, PICkit, PICtail, REAL ICE, rfLAB, Select Mode, Total Endurance, TSHARC, UniWinDriver, WiperLock and ZENA are trademarks of Microchip Technology Incorporated in the U.S.A. and other countries.

SQTP is a service mark of Microchip Technology Incorporated in the U.S.A.

All other trademarks mentioned herein are property of their respective companies.

Printed on recycled paper.

ISBN: 978-1-60932-782-8

Microchip received ISO/TS-16949:2002 certification for its worldwide headquarters, design and wafer fabrication facilities in Chandler and Tempe, Arizona; Gresham, Oregon and design centers in California and India. The Company’s quality system processes and procedures are for its PIC devices, Serial EEPROMs, microperipherals, nonvolatile memory and analog products. In addition, Microchip’s quality system for the design and manufacture of development systems is ISO 9001:2000 certified.

MCUs and dsPIC® DSCs, KEELOQ

code hopping

 2010 Microchip Technology Inc. DS22271A-page 41

Page 42

Worldwide Sales and Service

AMERICAS

Corporate Office

2355 West Chandler Blvd. Chandler, AZ 85224-6199 Tel: 480-792-7200 Fax: 480-792-7277 Technical Support:

http://support.microchip.com

Web Address:

www.microchip.com

Atlanta

Duluth, GA Tel: 678-957-9614 Fax: 678-957-1455

Boston

Westborough, MA Tel: 774-760-0087 Fax: 774-760-0088

Chicago

Itasca, IL Tel: 630-285-0071 Fax: 630-285-0075

Cleveland

Independence, OH Tel: 216-447-0464 Fax: 216-447-0643

Dallas

Addison, TX Tel: 972-818-7423 Fax: 972-818-2924

Detroit

Farmington Hills, MI Tel: 248-538-2250 Fax: 248-538-2260

Kokomo

Kokomo, IN Tel: 765-864-8360 Fax: 765-864-8387

Los Angeles

Mission Viejo, CA Tel: 949-462-9523 Fax: 949-462-9608

Santa Clara

Santa Clara, CA Tel: 408-961-6444 Fax: 408-961-6445

Toronto

Mississauga, Ontario, Canada Tel: 905-673-0699 Fax: 905-673-6509

ASIA/PACIFIC

Asia Pacific Office

Suites 3707-14, 37th Floor Tower 6, The Gateway Harbour City, Kowloon Hong Kong Tel: 852-2401-1200 Fax: 852-2401-3431

Australia - Sydney

Tel: 61-2-9868-6733 Fax: 61-2-9868-6755

China - Beijing

Tel: 86-10-8528-2100 Fax: 86-10-8528-2104

China - Chengdu

Tel: 86-28-8665-5511 Fax: 86-28-8665-7889

China - Chongqing

Tel: 86-23-8980-9588 Fax: 86-23-8980-9500

China - Hong Kong SAR

Tel: 852-2401-1200 Fax: 852-2401-3431

China - Nanjing

Tel: 86-25-8473-2460 Fax: 86-25-8473-2470

China - Qingdao

Tel: 86-532-8502-7355 Fax: 86-532-8502-7205

China - Shanghai

Tel: 86-21-5407-5533 Fax: 86-21-5407-5066

China - Shenyang

Tel: 86-24-2334-2829 Fax: 86-24-2334-2393

China - Shenzhen

Tel: 86-755-8203-2660 Fax: 86-755-8203-1760

China - Wuhan

Tel: 86-27-5980-5300 Fax: 86-27-5980-5118

China - Xian

Tel: 86-29-8833-7252 Fax: 86-29-8833-7256

China - Xiamen

Tel: 86-592-2388138 Fax: 86-592-2388130

China - Zhuhai

Tel: 86-756-3210040 Fax: 86-756-3210049

ASIA/PACIFIC

India - Bangalore

Tel: 91-80-3090-4444 Fax: 91-80-3090-4123

India - New Delhi

Tel: 91-11-4160-8631 Fax: 91-11-4160-8632

India - Pune

Tel: 91-20-2566-1512 Fax: 91-20-2566-1513

Japan - Yokohama

Tel: 81-45-471- 6166 Fax: 81-45-471-6122

Korea - Daegu

Tel: 82-53-744-4301 Fax: 82-53-744-4302

Korea - Seoul

Tel: 82-2-554-7200 Fax: 82-2-558-5932 or 82-2-558-5934

Malaysia - Kuala Lumpur

Tel: 60-3-6201-9857 Fax: 60-3-6201-9859

Malaysia - Penang

Tel: 60-4-227-8870 Fax: 60-4-227-4068

Philippines - Manila

Tel: 63-2-634-9065 Fax: 63-2-634-9069

Singapore

Tel: 65-6334-8870 Fax: 65-6334-8850

Tai wan - Hsin Chu

Tel: 886-3-6578-300 Fax: 886-3-6578-370

Taiwan - Kaohsiung

Tel: 886-7-213-7830 Fax: 886-7-330-9305

Taiwan - Taipei

Tel: 886-2-2500-6610 Fax: 886-2-2508-0102

Thailand - Bangkok

Tel: 66-2-694-1351 Fax: 66-2-694-1350

EUROPE

Austria - Wels

Tel: 43-7242-2244-39 Fax: 43-7242-2244-393

Denmark - Copenhagen

Tel: 45-4450-2828 Fax: 45-4485-2829

France - Paris

Tel: 33-1-69-53-63-20 Fax: 33-1-69-30-90-79

Germany - Munich

Tel: 49-89-627-144-0 Fax: 49-89-627-144-44

Italy - Milan

Tel: 39-0331-742611 Fax: 39-0331-466781

Netherlands - Drunen

Tel: 31-416-690399 Fax: 31-416-690340

Spain - Madrid

Tel: 34-91-708-08-90 Fax: 34-91-708-08-91

UK - Wokingham

Tel: 44-118-921-5869 Fax: 44-118-921-5820

08/04/10

DS22271A-page 42  2010 Microchip Technology Inc.

Datasheet RE46C190 Datasheet

Specifications and Main Features

Frequently Asked Questions

User Manual

1.0 ELECTRICAL CHARACTERISTICS

2.0 PIN DESCRIPTIONS

TABLE 2-1: PIN FUNCTION TABLE

3.0 DEVICE DESCRIPTION

3.1 St andby Internal Timing

3.2 Smoke Detection Circuitry

3.3 Supervisory Tests

3.4 Push-to-Test Operation (PTT)

3.5 Interconnect Operation

3.6 Reduc ed S e n s itivity Mode

3.7 Local Alarm Memory

3.8 End of Life Indicator

3.9 Photo Chamber Long Term Drift Adjustment

4.0 USER PROGRAMMING MODES

TABLE 4-1: PARAMETRIC PROGRAMMING

TABLE 4-2: FEATURES PROGRAMMING

4.1 Calibration and Programming Procedures

TABLE 4-3: TEST MODE FUNCTIONS

4.2 User Selections

FIGURE 4-1: Nominal Application Circuit for Programming.

FIGURE 4-2: Timing Diagram for Mode T0.

FIGURE 4-3: Circuit for Programming in the Typical Application.

4.3 Smoke Calibration

FIGURE 4-4: Timing Diagram for Modes T1 to T5.

4.4 Serial Read/Write

FIGURE 4-5: Timing Diagram for Mode T6.

4.5 Limits Verification

TABLE 4-4: LIMITS VERIFICATION DESCRIPTION

FIGURE 4-6: Timing Diagram for Modes T7-T10.

4.6 Horn Test

FIGURE 4-7: Timing Diagram for Mode T11.

5.0 APPLICATION NOTES

5.1 Standby Current Calculation and Battery Life

TABLE 5-1: STANDBY CURRENT CALCULATION

FIGURE 5-3: RE4 6C1 90 Timing Dia gram – Alar m Mem ory and Hus h Timer.

6.0 PACKAGING INFORMATION

6.1 Package Marking Information