Freescale Semiconductor
Technical Data
Document Number: MC145012
Rev 9.0, 11/2006
Photoelectric Smoke Detector IC with
I/O and Temporal Pattern Horn Driver
The CMOS MC145012 is an advanced smoke detector component containing
sophisticated very-low-power analog and digital circuitry. The IC is used with an
infrared photoelectric chamber. Detection is accomplished by sensing scattered
light from minute smoke particles or other aerosols. When detection occurs, a
pulsating alarm is sounded via on-chip push-pull drivers and an external
piezoelectric transducer.
The variable-gain photo amplifier allows direct interface to IR detectors
(photodiodes). Two external capacitors, C1 and C2, C1 being the larger, determine
the gain settings. Low gain is selected by the IC during most of the standby state.
Medium gain is selected during a local-smoke condition. High gain is used during
push-button test. During standby, the special monitor circuit which periodically
checks for degraded chamber sensitivity uses high gain also.
The I/O pin, in combination with V
SS
, can be used to interconnect up to 40 units
for common signaling. An on-chip current sink provides noise immunity when the I/
O is an input. A local-smoke condition activates the short-circuit-protected I/O
driver, thereby signaling remote smoke to the interconnected units. Additionally, the
I/O pin can be used to activate escape lights, enable auxiliary or remote alarms,
and/or initiate auto-dialers.
While in standby, the low-supply detection circuitry conducts periodic checks
using a pulsed load current from the LED pin. The trip point is set using two external
resistors. The supply for the MC145012 can be a 9.0 V battery.
A visible LED flash accompanying a pulsating audible alarm indicates a local-
smoke condition. A pulsating audible alarm with no LED flash indicates a remote-
smoke condition. A beep or chirp occurring virtually simultaneously with an LED
flash indicates a low-supply condition. A beep or chirp occurring halfway between
LED flashes indicates degraded chamber sensitivity. A low-supply condition does
not affect the smoke detection capability if V
DD
≥
6.0 V. Therefore, the low-supply
condition and degraded chamber sensitivity can be further distinguished by
performing a push-button (chamber) test.
Features
•
•
•
•
•
•
•
•
•
•
Circuit is designed to operate in smoke detector systems that comply with
UL217 and UL268 Specifications
Operating Voltage Range: 6.0 V to 12 V, Average Supply Current: 8
µA
Operating Temperature Range: -10 to 60°C
I/O Pin Allows Units to be Interconnected for Common Signalling
Power-On Reset Places IC in Standby Mode (Non-Alarm State)
Electrostatic Discharge (ESD) and Latch Up Protection Circuitry on All Pins
Chip Complexity: 2000 FETs, 12 NPNs, 16 Resistors, and 10 Capacitors
Supports NFPA 72, ANSI S3.41, and ISO 8201 Audible Emergency Evacuation
Signals
Ideal for battery-powered applications
Pb-Free Packaging Designated by Suffix Codes ED and EG
ORDERING INFORMATION
Device
MC145012P
648-08
MC145012ED
-55 to +125°C
MC145012DW
751G-04
MCZ145012EG/R2
16 SOICW (Pb-Free)
16 Lead SOICW
16 PDIP (Pb-Free)
Temp. Range
Case No.
Package
16 Lead Plastic Dip
MC145012
PHOTOELECTRIC SMOKE
DETECTOR IC WITH I/O AND
TEMPORAL PATTERN
HORN DRIVER
P SUFFIX
ED SUFFIX (PB-FREE)
PLASTIC DIP
CASE 648-08
DW SUFFIX
EG SUFFIX (PB-FREE)
SOIC PACKAGE
CASE 751G-04
C1
1
16
15
14
13
12
11
10
9
C2 2
DETECT 3
STROBE 4
VDD 5
IRED 6
I/O 7
BRASS 8
TEST
LOW-SUPPLY
TRIP
VSS
R1
OSC
LED
FEEDBACK
SILVER
Figure 1. Pin Connections
© Freescale Semiconductor, Inc., 2006. All rights reserved.
C1 C2
1 2
DETECT
3
AMP
V
DD
- 3.5 V
REF
Gain
Zero
Gate
On/off
-
COMP
+
Smoke
7
Alarm
Logic
Low Supply
Temporal Pattern Horn
Modulator
And Driver
I/O
12 OSC
OSC
13
R1
16
TEST
4
8
9
10
6
11
Timing
Logic
BRASS
SILVER
FEEDBACK
IRED
LED
GATE
ON/OFF
V
DD
- 5 V
REF
-
COMP
+
Pin 5 = V
DD
Pin 14 = V
SS
STROBE
LOW-SUPPLY 15
TRIP
Figure 2. Block Diagram
MC145012
2
Sensors
Freescale Semiconductor
Table 1. Maximum Ratings
All voltages are with respect to ground unless otherwise noted. Exceeding these ratings may cause a malfunction or permanent damage to the
device. (Voltages referenced to V
SS
)
Rating
DC Supply Voltage
DC Input Voltage
C1, C2, Detect
Osc, Low-Supply Trip
I/O
Feedback
Test
DC Input Current, per Pin
DC Output Current, per Pin
DC Supply Current, V
DD
and V
SS
Pins
Power Dissipation in Still Air
5 Seconds
Continuous
Storage Temperature
Lead Temperature, 1 mm from Case for 10 Seconds
Peak Package Reflow Temperature During Reflow
(3)
,
(4)
Symbol
V
DD
V
IN
-0.25
to V
DD
+0.25
-0.25
to V
DD
+0.25
-0.25
to V
DD
+10
-15
to +25
-1.0
to V
DD
+0.25
I
IN
I
OUT
I
DD
P
D
±10
±25
+25 /
-150
1200
350
(2)
T
STG
T
L
T
PPRT
(1)
Value
-0.5
to +12
Unit
V
V
mA
mA
mA
mW
-55
to +125
260
Note 4
°C
°C
°C
Note:
1.
Derating: -12 mW/°C from 25° to 60°C
2.
Derating:
-3.5 mW/×C from 25° to 60°C.
This device contains protection circuitry to guard against damage due to high static voltages or electric fields. However, precautions must
be taken to avoid applications of any voltage higher than maximum rated voltages to this high-impedance circuit. For proper operation, V
in
and V
out
should be constrained to the range V
SS
£ (V
in
or V
out
) £ V
DD
except for the I/O, which can exceed V
DD
, and the Test input, which
can go below V
SS
.
Unused inputs must always be tied to an appropriate logic voltage level (e.g., either V
SS
or V
DD
). Unused outputs and/or an unused I/O
must be left open.
3. Pin soldering temperature limit is for 10 seconds maximum duration. Not designed for immersion soldering. Exceeding these limits may
cause malfunction or permanent damage to the device.
4. Freescale’s Package Reflow capability meets Pb-free requirements for JEDEC standerd J-STD-020C. For Peak Package Reflow
Temperature and Moisture Sensitivity Levels (MSL),
> Go to
www.freescale.com
> Search by part number [e.g. remove prefixes/suffixes and enter the core ID to view all orderable parts. (ie. MC33xxxD enter 33xxx)]
> Locate your Part Number and in the Details column, select “View”
> Select “Environmental and Compliance Information”
MC145012
Sensors
Freescale Semiconductor
3
Table 2. Electrical Characteristics
(Voltages Referenced to V
SS
, T
A
= - 10 to 60°C Unless Otherwise Indicated).
Characteristic
Power Supply Voltage Range
Supply Threshold Voltage, Low-Supply Alarm
Average Operating Supply Current (per Package)
(Does Not Include Current through D3-IR Emitter)
Peak Supply Current (per Package)
(Does Not Include IRED Current into Base of Q1)
Symbol
V
DD
V
TH
I
DD
I
DD
Low-Supply Trip: V
in
= V
DD
/3
Standby
Configured per
Figure 8
During Strobe On, IRED Off
Configured per
Figure 8
During Strobe On, IRED On
Configured per
Figure 8
Low-Level Input Voltage
I/O
Feedback
Test
I/O
Feedback
Test
OSC, Detect
Low-Supply Trip
Feedback
Test
Test
I/O
V
IL
Test Condition
V
DD
V
—
—
12.0
12.0
12.0
9.0
9.0
9.0
9.0
9.0
9.0
V
in
= V
SS
or V
DD
V
in
= V
SS
or V
DD
V
in
= V
SS
or V
DD
V
in
= V
SS
V
in
= V
DD
No Local Smoke, V
in
= V
DD
No Local Smoke, V
in
= 17 V
I
out
= 10 mA
I
out
= 16 mA
I
out
= - 16 mA
Inactive, I
out
= 1
µA
Active, I
out
= 100
µA
to 500
µA
(Load Regulation)
Inactive, I
out
= 1
µA
Active, I
out
= 6 mA
(Load Regulation)
I
OH
Local Smoke, V
out
= 4.5 V
Local Smoke, V
out
= V
SS
(Short Circuit Current)
Off-State Output Leakage Current
Common Mode
Voltage Range
Smoke Comparator
Reference Voltage
Notes
5.
T
A
= 25°C only.
LED
C1, C2, Detect
Internal
I
OZ
V
IC
V
REF
V
out
= V
SS
or V
DD
Local Smoke, Push-button Test,
or Chamber Sensitivity Test
Local Smoke, Push-button Test,
or Chamber Sensitivity Test
12.0
12.0
12.0
12.0
9.0
9.0
12.0
6.5
6.5
6.5
—
9.0
Min
6.0
6.5
—
—
—
—
—
—
3.2
6.3
8.5
—
—
—
- 100
0.5
25
—
—
—
5.5
V
DD
- 0.1
V
DD
- 4.40
—
2.25
(5)
Max
12
7.8
8.0
2.0
3.0
1.5
2.7
7.0
—
—
—
±
100
±
100
±
100
- 1.0
10
100
140
0.6
1.0
—
—
V
DD
- 5.30
0.1
3.75
(5)
V
Unit
V
V
µA
mA
High-Level Input Voltage
V
IH
V
Input Current
I
IN
nA
Low-Level Input Current
Pull-Down Current
I
IL
I
IH
µA
µA
Low-Level Output Voltage
LED
Silver, Brass
Silver, Brass
Strobe
V
OL
V
OH
V
OUT
V
High-Level Output Voltage
Output Voltage
(For Line Regulation, See
Pin Descriptions)
V
V
IRED
—
9.0
High-Level Output Current
I/O
6.5
12.0
12.0
—
—
-4.0
—
—
V
DD
- 4.0
V
DD
- 3.08
—
-16
±1.0
V
DD
- 2.0
V
DD
- 3.92
mA
µA
V
V
MC145012
4
Sensors
Freescale Semiconductor
Table 3. AC Electrical Characteristics
(Reference Timing Diagram
Figure 6
and
Figure 7)
(T
A
= 25°C, V
DD
= 9.0 V, Component Values from
Figure 8:
R1 = 100.0 KΩ, C3 = 1500.0 pF, R2 = 7.5 MΩ).
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
Silver and Brass Chirp Pulse
Period
Silver and Brass Chirp Pulse
Width
Rising Edge on I/O to Smoke
Alarm Response Time
Strobe Out Pulse Period
IRED Pulse Width
IRED Rise Time
IRED Fall Time
Silver and Brass Temporal
Modulation Pulse Width
T
W(IRED)
T
R
T
F
T
ON
T
OFF
T
OFFD
T
CH
T
WCH
T
RR
T
STB
Remote Smoke,
No Local Smoke
Smoke Test
Chamber Sensitivity Test,
without Local Smoke
Low Supply Test,
without Local Smoke
Push-button Test
Low Supply or Degraded
Chamber Sensitivity
192
4096
1
—
1024
4096
4096
—
LED Pulse Width and Strobe
Pulse Width
IRED Pulse Period
IRED Pulse Period
T
W(LED)
,
T
W(STB)
T
IRED
T
IRED
Smoke Test
Chamber Sensitivity Test,
without Local Smoke
Push-button Test
Parameter
Oscillator Period
LED Pulse Period
Symbol
1/F
OSC
T
LED
Test Condition
Free-Running Sawtooth
Measured at Pin 12
No Local Smoke, and
No Remote Smoke
Remote Smoke, but
No Local Smoke
Local Smoke
Push-button Test
Clocks
1.0
4096
—
64
64
1.0
1024
4096
128
T
F
*
—
—
64
0.45
0.45
7.0
7.2
28.8
0.9
94
—
—
0.45
0.45
1.35
28.8
7.0
—
7.2
28.8
28.8
—
Min
(6)
7.0
28.8
Typ
(7)
7.9
32.4
Extinguished
—
—
—
8.1
32.4
1.0
—
—
—
0.5
0.5
1.52
32.4
7.9
2.0
(8)
8.1
32.4
32.4
1.0
—
—
8.6
8.8
35.2
1.1
116
30
200
0.55
0.55
1.65
35.2
8.6
—
8.8
35.2
35.2
—
s
ms
s
s
µs
s
µs
ms
s
s
Max
(6)
8.6
35.2
Unit
ms
s
Notes
6. Oscillator period T (= T
r
+ T
f
) is determined by the external components R1, R2, and C3 where T
R
= (0.6931) R
2
C
3
and T
F
= (0.6931) R
1
*
C
3
. The other timing characteristics are some multiple of the oscillator timing as shown in the table. The timing shown should accommodate
the NFPA 72, ANSI S3.41, and ISO 8201 audible emergency evacuation signals.
7. Typicals are not guaranteed.
8. Time is typical - depends on what point in cycle signal is applied.
MC145012
Sensors
Freescale Semiconductor
5
嵌入式系统
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
