MCP14A0153 Datasheet, PDF (12/30 Pages) Microchip Technology – 1.5A Dual MOSFET Driver with Low Threshold Input And Enable

MCP14A0153/4/5
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 Insulated-Gate Bipolar Transistors
(IGBTs). In high frequency switching power supplies,
the Pulse-Width Modulation (PWM) controller may not
have the drive capability to directly drive the power
MOSFET. A MOSFET driver such as the
MCP14A0153/4/5 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 is characterized by the
driver’s rise time (t_R), fall time (t_F) and propagation
delays (t_D1 and t_D2). Figure 4-1 and Figure 4-2 show
the test circuit and timing waveform used to verify the
MCP14A0153/4/5 timing.
V_DD = 18V
1 μF
0.1 μF
Input
½ MCP14A0153
½ MCP14A0155
Output
C_L = 1000 pF
5V
Input
V_IH (Typ.)
0V
18V
t_D1 t_F
V_IL (Typ.)
t_D2 t_R
90%
Output
0V
10%
FIGURE 4-1:
Waveform.
Inverting Driver Timing
V_DD = 18V
1 μF
0.1 μF
Input
½ MCP14A0154
½ MCP14A0155
Output
C_L = 1000 pF
5V
Input
V_IH (Typ.)
0V
18V
t_D1 t_R
V_IL (Typ.)
t_D2 t_F
90%
Output
0V
FIGURE 4-2:
Waveform.
10%
Noninverting Driver Timing
4.3 Enable Function
The enable pins (EN A,EN B) provide additional control
of the output pins (OUT). These pins are active high
and are internally pulled up to V_DD so that the pins can
be left floating to provide standard MOSFET driver
operation.
When the enable pin input voltage’s are above the
enable pin high voltage threshold, (V_{EN_H}), the
corresponding output is enabled and allowed to react to
the status of the Input pin. However, when the voltage
applied to the Enable pins falls below the low threshold
voltage (V_{EN_L}), the driver’s corresponding output is
disabled and doesn't respond to changes in the status
of the Input pins. When the driver is disabled, the
output is pulled down to a low state. Refer to Table 4-1
for the Enable pin logic. The threshold voltage levels for
the Enable pin are similar to the threshold voltage
levels of the Input pin, and are TTL compatible.
Hysteresis is provided to help increase the noise
immunity of the enable function, avoiding false triggers
of the enable signal during driver switching.
There are propagation delays associated with the
driver receiving an enable signal and the output
reacting. These propagation delays, t_D3 and t_D4, are
graphically represented in Figure 4-3.
DS20005470A-page 12
 2015 Microchip Technology Inc.