2005-2013 Microchip Technology Inc. DS21946B-page 9
TC4421A/TC4422A
3.0 PIN DESCRIPTIONS
The descriptions of the pins are listed in Table 3-1.
TABLE 3-1: PIN FUNCTION TABLE
3.1 Supply Input (V
DD
)
The V
DD
input is the bias supply for the MOSFET driver
and is rated for 4.5V to 18V with respect to the ground
pin. The V
DD
input should be bypassed to ground with
a local ceramic capacitor. The value of the capacitor
should be chosen based on the capacitive load that is
being driven. A minimum value of 1.0 µF is suggested.
3.2 Control Input
The MOSFET driver input is a high-impedance,
TTL/CMOS-compatible input. The input also has
300 mV of hysteresis between the high and low
thresholds that prevents output glitching even when the
rise and fall time of the input signal is very slow.
3.3 CMOS Push-Pull Output
The MOSFET driver output is a low-impedance,
CMOS, push-pull style output capable of driving a
capacitive load with 9.0A peak currents. The MOSFET
driver output is capable of withstanding 1.5A peak
reverse currents of either polarity.
3.4 Ground
The ground pins are the return path for the bias current
and for the high peak currents that discharge the load
capacitor. The ground pins should be tied into a ground
plane or have very short traces to the bias supply
source return.
3.5 Exposed Metal Pad
The exposed metal pad of the 6x5 DFN package is not
internally connected to any potential. Therefore, this
pad can be connected to a ground plane or other
copper plane on a Printed Circuit Board (PCB) to aid in
heat removal from the package.
3.6 Metal Tab
The metal tab of the TO-220 package is connected to
the V
DD
potential of the device. This connection to V
DD
can be used as a current carrying path for the device.
Pin No.
8-Pin PDIP,
SOIC
Pin No.
8-Pin DFN
Pin No.
5-Pin TO-220
Symbol Description
11—V
DD
Supply input, 4.5V to 18V
2 2 1 INPUT Control input, TTL/CMOS-compatible input
3 3 — NC No connection
4 4 2 GND Ground
5 5 4 GND Ground
6 6 5 OUTPUT CMOS push-pull output
7 7 — OUTPUT CMOS push-pull output
883V
DD
Supply input, 4.5V to 18V
—PAD— NCExposed metal pad
——TABV
DD
Metal tab is at the V
DD
potential
