P

AC

MAIN

S

N

LOAD

C1

T1

L1

R1

A

B

R4

C3

D1

5

6

7

8

4

3

2

1

C5

C4

TRIG

OFF

ON

OSC

CAP SYNC

+

LS7339

FIGURE 5. A TYPICAL AUTO SHUT-OFF AC POWER SWITCH

G

MT2

MT1

Z1

-

R5

C7

R8

C6

SEE

NOTE 1

SEE

NOTE 2

R7

R6

R2

R3

C2

ON

OFF

S1

-

+

NOTES:

1. Use Connection A when Neutral is not available.

Use Connection B when Neutral is available.

2. Snubber Network C7, R8 may be required for

some inductive loads.

3. See Table 2 for Component Functional Description.

7339-012703-4

115VAC

220VAC

(1)(3) R1 150

Ω, 1W

360

Ω, 2W

(2)(4) R1 82

Ω

82

Ω

R2 1.5M

Ω

1.5M

Ω

R3 100k

Ω

100k

Ω

R4 100k

Ω

100k

Ω

R5 100

Ω

100

Ω

R6 (5)(6)

(5)(6)

R7 (5)(6)

(5)(6)

R8 1.8k

Ω, 1W

1.8k

Ω, 2W

C1

0.15µF, 200V 0.15µF, 400V

(1) C2

1.0µF, 200V

0.47µF, 400V

(2) C2

0.47µF, 200V 0.22µF, 400V

(3) C2

0.33µF, 200V 0.22µF, 400V

(4) C2

0.22µF, 200V 0.1µF, 400V

(1)(2) C3

100µF

100µF

(3)(4) C3

47µF

47µF

C4

470pF

470pF

C5

0.047µF

0.047µF

C6

(6)

(6)

C7

0.1µF, 200V

0.1µF, 400V

Z1

15V, 1/2W

15V, 1/2W

D1

1N4148

1N4148

L1

100µH

200µH

(7)T1

Q4008L4

Q5004L4

(1) LS7339, Connection A

(7) Typical

(2) LS7339, Connection B

(3) LS7340, Connection A

(4) LS7340, Connection B

(5) 100k

Ω ≤ (R6 + R7) ≤10MΩ

(6) (R6 + R7)C6

≥ 5ms

All Resistors 1/4W, all Capacitors 25V

FIGURE 6. PRODUCING VERY LONG TIME-OUTS BY PULSE MODULATING THE OSCILLATOR

Oscillator

Components

R2

R1

CD4093

C1 = 0.1µF

-V

R3

C2

-

+

4

3

TRIG

OSC

5

6

2

1

8

7

OFF

ON

CAP SYNC

T1

T2

Waveform A

LS7339

T1

≈ R1 C1

T2

≈ (R1 + R2)C1

D1

T1

Period = T1 + T2

Pulse Duty Cycle = T1/Period

-V

Waveform B (Pulse Modulator)

Inverse of Pulse Duty Cycle = Period/T1 = 1 +T2/T1 = 2 + R2/R1

Waveform A

Waveform B

+V

D2

DESCRIPTION:

The Oscillator resistor is normally returned to the negative terminal of the DC Supply.

If this resistor is returned to a negative-going pulse instaed, the Oscillator R-C effectively

becomes multiplied by the inverse of the Pulse Duty Cycle because the Oscillator R-C can

chamge only while the pulse is present. (Pulse Modulation)

In Figure 6, The Oscillator R is R3, the Oscillator C is C2 and the Pulse Modulator is

Waveform B through isolation diode D2. The Multiplier, M = 2 + R2/R1 (the inverse of

the Pulse Duty Cycle).

EXAMPLE:

R3 = 5.1M

Ω, C2 = 1.0uF, Pulse Modulator = Waveform B

Oscillator Components. With M = 22, R2/R1 = 20. If R2 = 3M

Ω, R1 = 150kΩ