4-179

TELCOM SEMICONDUCTOR, INC.

7

6

5

4

3

1

2

8

Table 1. Maximum Operating Frequencies

18V

500 kHz

15V

700 kHz

10V

1.3 MHz

5V

>2 MHz

CONDITIONS: 1. CerDIP Package (

Three components make up total package power dissi-

pation:

The capacitive load-caused dissipation is a direct func-

tion of frequency, capacitive load, and supply voltage. The

package power dissipation is:

where: f = Switching frequency

C = Capacitive load

Quiescent power dissipation depends on input signal

duty cycle. A logic low input results in a low-power dissipa-

tion mode with only 0.5 mA total current drain. Logic high

signals raise the current to 5 mA maximum. The quiescent

power dissipation is:

D = Duty cycle.

Transition power dissipation arises because the output

stage N- and P-channel MOS transistors are ON simulta-

neously for a very short period when the output changes.

The transition package power dissipation is approximately:

An example shows the relative magnitude for each item.

Example 1:

C = 2500 pF

D = 50%

f

= 200 kHz

= 113 mW + 10 mW + 41 mW

= 164 mW.

= 125

°C,

(+150

°C)

(150

°C/W, CerDIP).

NOTE:

Ambient operating temperature should not exceed +85

°C for

IJA devices or +125

°C for MJA devices.

Peak Output Current Capability

POWER-ON OSCILLATION

It is extremely important that all MOSFET DRIVER

applications be evaluated for the possibility of having

HIGH-POWER OSCILLATIONS occurring during the

POWER-ON cycle.

POWER-ON OSCILLATIONS are due to trace size and

layout as well as component placement. A ‘quick fix’ for most

applications which exhibit POWER-ON OSCILLATION prob-

lems is to place approximately 10 k

Ω in series with the input

of the MOSFET driver.

200

0

400

600

800

1000

1200

1400

1600

0

10

20

30

40

50

60

70

80

90

100

110

120

AMBIENT TEMPERATURE (

°C)

8 Pin DIP

Thermal Derating Curves

8 Pin CerDIP

8 Pin SOIC

TC429

6A SINGLE HIGH-SPEED,

CMOS POWER MOSFET DRIVER