DocID3572 Rev 4

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Thermal rating of Triac

17

3

Thermal rating of Triac

case conditions allows the definition of the Triac power dissipation (see Equation 12 and

Equation 13

).

Where:

•

•

•

•

F the AC line frequency.

Equation 12

With

Equation 13

Equation 14

and Equation 15 define the junction temperature of the Triac according to the

ambient to junction thermal resistance and case to junction thermal resistance.

Equation 14

Equation 15

10

, Equation 11, Equation 12 and Equation 13.

()

()

2

4

M

p

t

to

M

p

T

IT

F

t

R

V

IT

F

t

P

•

•

•

+

•

•

•

•

=

π

F

t

IT

IT

p

M

RMS

•

•

=

()

T

AC

c

j

TH

C

J

P

R

T

T

•

=

-

-

()

T

a

c

TH

amb

C

P

R

T

T

•

=

-

-