34653 datasheet(21/24 Pages) FREESCALE

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Analog Integrated Circuit Device Data

Freescale Semiconductor

34653

TYPICAL APPLICATIONS

POWER MOSFET ENERGY CAPABILITY

Figure 23 shows a projected energy capability of the

device’s internal Power MOSFET under a drain-to-source

voltage of 82 V and an ambient temperature of 90°C. It is

compared to the energy levels required for the capacitive

loads of 100

µF, 200 µF, and 400 µF at 80 V for the

discharge periods of 16 ms, 32 ms, and 64 ms, respectively.

It is clear that the Power MOSFET well exceeds the required

energy capability for all three cases with a sufficient margin.

For example, the 400

µF capacitor load with a 64 ms

discharge time requires an energy capability of about

1540 mJ, which is well below the Power MOSFET capability

of about 3500 mJ. As a result to this analysis the 33652 is

expected to exceedingly meet all the energy capability

requirements for the possible capacitive loads.

Figure 23. Projected Energy Capability of the Power

MOSFET Compared to the Required Energy Levels of

Some Capacitive Loads

400

µF

200

µF

100

µF

Estimated for Area =1.7 mm2

500

1000

1500

2000

2500

3000

3500

Time (ms)

020

34653 Datasheet(PDF) 21 Page - Freescale Semiconductor, Inc