NCV8184

http://onsemi.com

11

0.1

1

10

100

0.000001

0.00001

0.0001

0.001

0.01

0.1

1

10

100

1000

t1 (s)

Figure 30. DPAK 5−Lead Thermal Duty Cycle Curves on 1.0 in. Spreader Test Board

(1.0 in pad PCB) Die Size = 2.08 x 1.55 x 0.40 5.0% Active Area

50% Duty Cycle

20%

Single Pulse

10%

5%

2%

1%

Duty Cycle, D =

t 1

t 2

PDM

Notes:

t 1

t 2

0.1

1

10

100

1000

0.000001

0.00001

0.0001

0.001

0.01

0.1

1

10

100

1000

Time (s)

Figure 31. DPAK 5−Lead Thermal Transient Response on Typical Test Boards

Die Size = 2.08 x 1.55 x 0.40 5.0% Active Area

Junction

Ambient

(thermal ground)

Time constants are not simple RC products.

Amplitudes of mathematical solution are not the resistance values.

Figure 32. Grounded Capacitor Thermal Network (“Cauer” Ladder)

Figure 33. Non−Grounded Capacitor Thermal Ladder (“Foster” Ladder)

Junction

Ambient

(thermal ground)

Each rung is exactly characterized by its RC−product time constant;

Amplitudes are the resistances