MMFT2955E

6

Motorola TMOS Power MOSFET Transistor Device Data

Figure 14. Capacitance Variation with Voltage

SAME

DEVICE TYPE

AS DUT

Vin

+18 V

VDD

10 V

100 k

0.1

µF

FERRITE

BEAD

DUT

100

2N3904

2N3904

47 k

15 V

100 k

Vin = 15 Vpk; PULSE WIDTH ≤ 100 µs, DUTY CYCLE ≤ 10%.

1mA

47 k

1000

800

200

400

600

0

Figure 15. Gate Charge versus Gate–To–Source Voltage

GATE–TO–SOURCE OR DRAIN–TO–SOURCE VOLTAGE (VOLTS)

Ciss

Figure 16. Gate Charge Test Circuit

1200

1400

1600

1800

Crss

Coss

Ciss

Coss

Crss

VGS

15

10

5

0

5

10

15

20

VDS

Qg, TOTAL GATE CHARGE (nC)

0

10

3

7.5

13

20

9

8

7

6

5

4

3

2

1

0

TJ = 25°C

VDS = 48 V

ID = 1.2 A

VGS

VDS

TJ = 25°C

f = 1 MHz