Sensors

4

Freescale Semiconductor

MC145010

Table 3. AC Electrical Characteristics

C3 = 1500.0 pF, R2 = 10.0 M

Ω.)

No.

Characteristics

Symbol

Clocks

Min

Max

Unit

1

Free-Running Sawtooth Measured at Pin 12

The other timing characteristics are some multiple of the oscillator timing shown in the table.

1

9.5

11.5

ms

2

3

4

LED Pulse Period

No Local Smoke, and No Remote Smoke

Remote Smoke, but No Local Smoke

Local Smoke or Push Button Test

4096

—

64

38.9

—

0.60

47.1

—

0.74

s

5

LED Pulse Width and Strobe Pulse Width

1

9.5

11.5

ms

6

7

8

IRED Pulse Period

Smoke Test

Chamber Sensitivity Test without Local Smoke

Push Button Test

1024

4096

32

9.67

38.9

0.302

11.83

47.1

0.370

s

9

IRED Pulse Width

94

116

µs

10

IRED Rise Time

IRED Fall Time

—

—

—

—

30

200

µs

11

Silver and Brass Modulation Period

Local or Remote Smoke

—

297

363

ms

11

12

Silver and Brass Duty Cycle

Local or Remote Smoke

—

73

77

%

13

Silver and Brass Chirp Pulse Period

Low Supply or Degraded Chamber Sensitivity

4096

38.9

47.1

s

14

Silver and Brass Chirp Pulse Width

Low Supply or Degraded Chamber Sensitivity

1

9.5

11.5

ms

15

Rising Edge on I/O to Smoke Alarm Response Time

Remote Smoke, No Local Smoke

—

—

800

ms

16

17

18

19

Strobe Out Pulse Period

Smoke Test

Chamber Sensitivity Test without Local Smoke

Low Supply Test without Local Smoke

Push Button Test

1024

4096

4096

—

9.67

38.9

38.9

0.302

11.83

47.1

47.1

0.370

s