3/8/2001

5

215 Topaz Street, Milpitas, California 95035



Tel: (408) 263-3214

Fax: (408) 263-7846

www.calmicro.com

PACNLT101

©2001 California Micro Devices Corp. All rights reserved. EZterm™ is a trademark of California Micro Devices

Enable pin

In normal use the Enable pin is connected to V

If the Enable pin is set to 0V or disconnected (high

impedance), then the PACNLT101 will be disabled. The

supply current will drop to almost zero and the clamping

performance will be worsened.

The Enable pin can also be used to vary the supply

current and clamping voltage. As the current into the

Enable pin is increased the supply current will increase

and the clamping voltage will be reduced. The minimum

clamping voltage will occur when the Enable pin voltage

equals the supply voltage. (The Enable pin voltage

cannot exceed the supply voltage.)

Users who cannot tolerate the supply current quoted in

the Operating Characteristics can connect a resistor in

series with the Enable pin to reduce the supply current,

at the cost of increasing the clamping voltage. See

Figure 6.

The controller IC sets the powerdown pin to 0V to

powerdown the PACNLT101, and sets the powerdown

pin to V

designer can vary the value of R1 to optimize the trade-

off between power consumption and clamping voltage.

See Figure 7, 8, 9, and 10.

Figure 7. I

Figure 6. Resistor In Series with the Enable Pin

Controller

Powerdown

PACNLT101

R1

Enable

0

10

20

30

40

50

60

70

80

90

100

0

100

220

470

1000

2200

Value of External Resistor R1 (

Ω)

500

550

600

650

700

750

800

0

100

220

470

1000

2200

Value of External Resistor R1 (

Ω)

Figure 8. Clamping Voltage vs R1 @ V

Figure 9. I

Figure 10. Clamping Voltage vs R1 @ V

0

5

10

15

20

25

30

0

100

220

470

1000

2200 4700 10000 100000

Value of External Resistor R1 (

Ω)

300

350

400

450

550

500

600

650

0

100

220

470

1000

2200

4700 10000 100000

Value of External Resistor R1 (

Ω)