AN2266 datasheet(7/16 Pages) STMICROELECTRONICS

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AN2266

LCP topology based protection family

They are two kinds of protection product families based on the LCP concept:

The LCP152xx protects lines within the range from GND to -Vbat. The electrical

characteristic, given in Figure 8, shows the asymmetrical behavior of this protection

function. The Vgate threshold voltage is controlled by the negative bias voltage applied on

the gate pin. This voltage can be within the range from 0 to -150 V for the LCP152xx.

Figure 8. LCP152xx circuit and electrical characteristic

The LCP02-150xx is designed to protect lines where the normal operating voltage can be

negative or positive, and located between -Vbat and +Vb. The electrical characteristic, given

in Figure 9, shows a crowbar adjustable function for both positive and negative areas of the

curve. The knee of the positive part of the curve is controlled by the Gp gate bias while the

knee of the negative part is controlled by the Gn gate bias.

Figure 9. LCP02-150xx circuit and electrical characteristic

Gate

Tip

Ring

GND

Vgate

Tip

Ring

GND

Vgn

Ih+

Vgp

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