FAN3100T Fairchild Semiconductor, FAN3100T Datasheet - Page 16

• Manufacturer Part Number: FAN3100T
• Description: The FAN3100 2A gate driver is designed to drive an N-channel enhancement-mode MOSFET in low-side switching applications by providing high peak current pulses during the short switching intervals
• Manufacturer: Fairchild Semiconductor

© 2007 Fairchild Semiconductor Corporation
FAN3100 • Rev. 1.0.3
Figure 44 shows the current path when the gate driver
turns the MOSFET off. Ideally, the driver shunts the
current directly to the source of the MOSFET in a small
circuit loop. For fast turn-off times, the resistance and
inductance in this path should be minimized.
Truth Table of Logic Operation
The FAN3100 truth table indicates the operational states
using the dual-input configuration. In a non-inverting
driver configuration, the IN- pin should be a logic low
signal. If the IN- pin is connected to logic high, a disable
function is realized, and the driver output remains low
regardless of the state of the IN+ pin.
In the non-inverting driver configuration in Figure 45, the
IN- pin is tied to ground and the input signal (PWM) is
applied to IN+ pin. The IN- pin can be connected to logic
high to disable the driver and the output remains low,
regardless of the state of the IN+ pin.
In the inverting driver application shown in Figure 46, the
IN+ pin is tied high. Pulling the IN+ pin to GND forces the
output low, regardless of the state of the IN- pin.
Figure 44. Current Path for MOSFET Turn-Off
IN+
0
0
1
1
Figure 45. Dual-Input Driver Enabled,
Figure 46. Dual-Input Driver Enabled,
Non-Inverting Configuration
Inverting Configuration
IN-
0
1
0
1
OUT
0
0
1
0
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