Datasheet
MCP1415/16
DS22092E-page 10 2008-2012 Microchip Technology Inc.
4.0 APPLICATION INFORMATION
4.1 General Information
MOSFET drivers are high-speed, high current devices
which are intended to source/sink high peak currents to
charge/discharge the gate capacitance of external
MOSFETs or IGBTs. In high frequency switching power
supplies, the PWM controller may not have the drive
capability to directly drive the power MOSFET. A
MOSFET driver like the MCP1415/16 family can be
used to provide additional source/sink current
capability.
4.2 MOSFET Driver Timing
The ability of a MOSFET driver to transition from a fully-
off state to a fully-on state are characterized by the
drivers rise time (t
R
), fall time (t
F
), and propagation
delays (t
D1
and t
D2
). The MCP1415/16 family of drivers
can typically charge and discharge a 1000 pF load
capacitance in 20 ns along with a typical turn on (t
D1
)
propagation delay of 41 ns. Figure 4-1 and Figure 4-2
show the test circuit and timing waveform used to verify
the MCP1415/16 timing.
FIGURE 4-1: Inverting Driver Timing
Waveform.
FIGURE 4-2: Non-Inverting Driver Timing
Waveform.
4.3 Decoupling Capacitors
Careful layout and decoupling capacitors are required
when using power MOSFET drivers. Large current are
required to charge and discharge capacitive loads
quickly. For example, approximately 720 mA are
needed to charge a 1000 pF load with 18V in 25 ns.
To operate the MOSFET driver over a wide frequency
range with low supply impedance, a ceramic and a low
ESR film capacitor are recommended to be placed in
parallel between the driver V
DD
and GND. A 1.0 µF low
ESR film capacitor and a 0.1 µF ceramic capacitor
placed between pins 2 and 4 is required for reliable
operation. These capacitors should be placed close to
the driver to minimize circuit board parasitics and
provide a local source for the required current.
0.1 µF
+5V
10%
90%
10%
90%
10%
90%
18V
1µF
0V
0V
MCP1415
C
L
= 1000 pF
Input
Input
Output
t
D1
t
F
t
D2
Output
t
R
V
DD
= 18V
Ceramic
90%
Input
t
D1
t
F
t
D2
Output
t
R
10%
10%
10%
+5V
18V
0V
0V
90%
90%
0.1 µF
1µF
MCP1416
C
L
= 1000 pF
Input Output
V
DD
= 18V
Ceramic