A

8/97

TOP209/210

13

1.2

1.0

0.8

0.6

0.4

0.2

0

-50 -25

0

25

50

75 100 125 150

Junction Temperature (

°C)

CURRENT LIMIT vs. TEMPERATURE

The following precautions should be followed when testing

TOPSwitch by itself outside a power supply. The schematic

shown in Figure 12 is suggested for laboratory testing of

TOPSwitch.

When the DRAIN supply is turned on, the part will be in the

auto-restart mode.

The CONTROL pin voltage will be

oscillating at a low frequency from 4.7 to 5.7 V and the DRAIN

is turned on every eighth cycle of the CONTROL pin oscillation.

BENCH TEST PRECAUTIONS FOR EVALUATION OF ELECTRICAL CHARACTERISTICS

1.2

1.0

0.8

0.6

0.4

0.2

0

-50 -25

0

25

50

75 100 125 150

Junction Temperature (

°C)

FREQUENCY vs. TEMPERATURE

If the CONTROL pin power supply is turned on while in this

auto-restart mode, there is only a 12.5% chance that the

CONTROL pin oscillation will be in the correct state (DRAIN

active state) so that the continuous DRAIN voltage waveform

may be observed. It is recommended that the V

be turned on first and the DRAIN power supply second if

continuous DRAIN voltage waveforms are to be observed.

The 12.5% chance of being in the correct state is due to the 8:1

counter.

Typical Performance Characteristics

2

1.2

1.6

0

0

204060

80

100

DRAIN Voltage (V)

0.4

0.8

VC = 5 V

1.1

1.0

0.9

-50 -25

0

25

50

75 100 125 150

Junction Temperature (

°C)

BREAKDOWN vs. TEMPERATURE