Microchip Technology TC4451, Manual

Page: 10 / 24

TC4451/TC4452
DS20001987C-page 10

2006-2014 Microchip Technology Inc.
3.0 PIN DESCRIPTIONS
The descriptions of the pins are listed in Table 3-1 .
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 (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 (OUTPUT,
OUTPUT)
The MOSFET driver output is a low-impedance,
CMOS, push-pull style output capable of driving a
capacitive load with 12A peak currents. The MOSFET
driver output is capable of withstanding 1.5A peak
reverse currents of either polarity.
3.4 Ground (GND)
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 Thermal Pad (EP)
The exposed thermal pad of the 6x5 DFN-S 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 help
remove heat from the package.
3.6 Thermal Tab
The thermal tab of the TO-220 package is connected to
the V
DD
potential of the device and this connection is
used as a current-carrying path.
TABLE 3-1: PIN FUNCTION TABLE
8-Pin PDIP,
SOIC
8-Pin DFN-S 5-Pin TO-220 Symbol Description
1 1 — 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/OUTPUT CMOS push-pull output
7 7 — OUTPUT/OUTPUT CMOS push-pull output
8 8 3 V
DD
Supply input, 4.5V to 18V
— 9 — EP Exposed thermal pad
— — TAB V
DD
Thermal tab is at the V
DD
potential