PIC18F25J11-I/PT MICROCHIP [Microchip Technology], PIC18F25J11-I/PT Datasheet - Page 252

• Manufacturer Part Number: PIC18F25J11-I/PT
• Description: 28/44-Pin, Low-Power, High-Performance Microcontrollers with nanoWatt XLP Technology
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18F46J11 FAMILY
17.5.1
In Half-Bridge mode, two pins are used as outputs to
drive push-pull loads. The PWM output signal is output
on the PxA pin, while the complementary PWM output
signal is output on the PxB pin (see Figure 17-8). This
mode can be used for half-bridge applications, as
shown in Figure 17-9, or for full-bridge applications,
where four power switches are being modulated with
two PWM signals.
In Half-Bridge mode, the programmable dead-band delay
can be used to prevent shoot-through current in
half-bridge power devices. The value of the PxDC<6:0>
bits of the ECCPxDEL register sets the number of
instruction cycles before the output is driven active. If the
value is greater than the duty cycle, the corresponding
output remains inactive during the entire cycle. See
Section 17.5.6 “Programmable Dead-Band Delay
Mode” for more details of the dead-band delay
operations.
FIGURE 17-9:
DS39932C-page 252
Standard Half-Bridge Circuit (“Push-Pull”)
Half-Bridge Output Driving a Full-Bridge Circuit
HALF-BRIDGE MODE
EXAMPLE OF HALF-BRIDGE APPLICATIONS
PxA
PxB
PxA
PxB
FET
Driver
FET
Driver
FET
Driver
FET
Driver
Since the PxA and PxB outputs are multiplexed with the
PORT data latches, the associated TRIS bits must be
cleared to configure PxA and PxB as outputs.
FIGURE 17-8:
PxA
PxB
td = Dead-Band Delay
Note 1: At this time, the TMR2 register is equal to the
(2)
(2)
2: Output signals are shown as active-high.
(1)
Load
V+
td
PR2 register.
Pulse Width
Period
Load
td
EXAMPLE OF
HALF-BRIDGE PWM
OUTPUT
© 2009 Microchip Technology Inc.
FET
Driver
FET
Driver
(1)
+
-
+
-
Period
(1)