TDE1798DP datasheet(6/14 Pages) STMICROELECTRONICS

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= V(BR)

[Io

−

V(BR) − VCC

Log

( 1 +

VCC

V(BR) − VCC

) ]

SHORT CIRCUIT CONDITIONS WITH CONTROLLED RESET

DEMAGNETIZATION OF INDUCTIVE LOADS

WITHOUT EXTERNAL CLAMPING DEVICES.

With no external clamping device, the energy of

demagnetization is dissipated in the TDE1798

output stage, and the clamping voltage is the col-

lector -emitter breakdown voltage V(BR)CEO.

This method provides a very fast demagnetization

of inductive loads and can be used up to 150 mJ.

The amount of energy W dissipated in the output

stage during a demagnetizationis :

Remark 1 : This energy is dissipated inside the

case, then must be included in the whole power

dissipation.

Remark 2 : The use of external clamping device

is recommended in case of parallel driving of

loads. The dispersion of the collector-emitter

breakdown voltage V(BR) would induce the circuit

with the lowest V(BR) to dissipate the whole de-

magnetization energy (which is roughly propor-

tionnal to IO

2).

TDE1798

6/14

TDE1798DP Datasheet(PDF) 6 Page - STMicroelectronics