CLP270M

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The operating point moves to region 5 for positive surges or region 6 for negative surges.

(region 4).

In normal operating condition the current (typically below -100 mA) should not activate the protection

device CLP270M. Therefore the level of activation is to be chosen just above this limit (-200 mA). This level

EXAMPLE :

Ω ensures a negative triggering of -190 mA min and -320 mA max. In this case, the

positive triggering will be 150mA min and 280 mA max.

2.5. Failure Status

The CLP270M has an internal feature that allows the user to get a Failure Status (FS) indication. When the

CLP270M is short-circuiting the line to GND, a signal can be managed through pin 1. This signal can be

used to turn a LED on in order to provide a surge indication. It may also be used with a logic circuitry to

count the number of disturbances appearing on the lines.

If a surge exceeding the maximum ratings of the CLP270M occurs on the line, the device will fail in a

short-circuit state.

3

5

7

9

11

13

0.2

0.3

0.5

1

2

Rsense ( )

Ω

ISWON (T, Rsense) / ISWON (25°C, 4

)

Ω

@-20°C @25°C

@75°C

35

7

9

11

50

100

200

300

500

Rsense ( )

Ω

Iswon @ 25°C (mA)

Iswon min

negative

Iswon max

negative

Iswon min

positive

Iswon max

positive

CLP270M

Rsense

Rsense

1

FAILURE

+12V

1k

STATUS

Fig. 8: Failure Status circuit and diagnostic.

0.01

0.02

0.05

0.1

0.2

0.5

1

2

5

10

10

20

50

100

200

500

1 000

2 000

5 000

t (ms)

Fig. 9 : Operation limits and destruction zone of

the CLP270M.