FOD3181 Datasheet, PDF (11/12 Pages) Fairchild Semiconductor – 0.5A Ouput Current, High Speed MOSFET Gate Driver Optocoupler

I_OH and I_OL Test Conditions
This device is tested and specified when driving a complex
reactive load. The load consists of a capacitor in the series with
a current limiting resistor. The capacitor represents the gate to
source capacitance of a power MOSFET transistor. The test
load is a 0.03uF capacitor in series with an 40Ω resistor. The
LED test frequency is 10.0kHz with a 50% duty cycle. The com-
bined I_OH and I_OL output load current duty factor is 0.6% at the
test frequency.
Figure 14 illustrates the relationship of the LED input drive
current and the device’s output voltage and sourcing and sink-
ing currents. The 0.03µF capacitor load represents the gate to
source capacitance of a very large power MOSFET transistor.
A single supply voltage of 20V is used in the evaluation.
Figure 15 shows the test schematic to evaluate the output volt-
age and sourcing and sinking capability of the device. The I_OH
and I_OL are measured at the peak of their respective current
pulses.
LED
20V
OUTPUT
0
Load
Current
I_F = 8mA
ON
P-Channel (ON)
I_OH = 0.5A
OFF
N-Channel (ON)
I_OL = 0.5A
1µs/Div
Figure 14. FOD 3180 Output Current and Output Voltage vs. LED Drive
Pulse
Generator
1
2
IF_MON
3
100Ω
100Ω
4
FOD3181
8
7 ^VO
0.33µF
6
0.1µF
IO_MON
40Ω
22µF
5
Figure 15. Test Schematic
11
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FOD3181 Rev. 1.0.3