PIC18F87J11T-I/PT Microchip Technology, PIC18F87J11T-I/PT Datasheet - Page 217

• Manufacturer Part Number: PIC18F87J11T-I/PT
• Description: IC PIC MCU FLASH 64KX16 80TQFP
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18F87J11T-I/PT

• Core Size: 8-Bit
• Program Memory Size: 128KB (64K x 16)
• Oscillator Type: Internal
• Core Processor: PIC
• Speed: 48MHz
• Connectivity: EBI/EMI, I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LVD, POR, PWM, WDT
• Number Of I /o: 68
• Program Memory Type: FLASH
• Ram Size: 3930 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 3.6 V
• Data Converters: A/D 15x10b
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 80-TFQFP
• Controller Family/series: PIC18
• No. Of I/o's: 68
• Ram Memory Size: 3930Byte
• Cpu Speed: 48MHz
• No. Of Timers: 5
• No. Of Pwm: RoHS Compliant
• Processor Series: PIC18F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 3904 B
• Interface Type: EUSART, I2C, MSSP, SPI
• Maximum Clock Frequency: 48 MHz
• Number Of Programmable I/os: 68
• Number Of Timers: 5
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734, 52712-325, EWPIC18
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, DM183032, DM183022, DV164136
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 15 Channel
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: DV164136 - DEVELOPMENT KIT FOR PIC18AC162091 - HEADER MPLAB ICD2 18F87J11 64/80MA180020 - MODULE PLUG-IN HPC EXPL 18F87J11AC164328 - MODULE SKT FOR 80TQFP
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details
• Other names: PIC18F87J11T-I/PTTR

18.4.6
In half-bridge applications, where all power switches
are modulated at the PWM frequency at all times, the
power switches normally require more time to turn off
than to turn on. If both the upper and lower power
switches are switched at the same time (one turned on
and the other turned off), both switches may be on for
a short period of time until one switch completely turns
off. During this brief interval, a very high current
(shoot-through current) may flow through both power
switches, shorting the bridge supply. To avoid this
potentially destructive shoot-through current from flow-
ing during switching, turning on either of the power
switches is normally delayed to allow the other switch
to completely turn off.
In the Half-Bridge Output mode, a digitally program-
mable, dead-band delay is available to avoid
shoot-through current from destroying the bridge
power switches. The delay occurs at the signal
transition from the non-active state to the active state
(see Figure 18-4 for illustration). The lower seven bits of
the ECCPxDEL register (Register 18-2) set the delay
period in terms of microcontroller instruction cycles
(T
© 2009 Microchip Technology Inc.
CY
or 4 T
OSC
PROGRAMMABLE DEAD-BAND
DELAY
).
PIC18F87J11 FAMILY
18.4.7
When the ECCP1 is programmed for any of the
Enhanced PWM modes, the active output pins may be
configured for auto-shutdown. Auto-shutdown immedi-
ately places the Enhanced PWM output pins into a
defined shutdown state when a shutdown event
occurs.
A shutdown event can be caused by either of the two
comparator modules or the FLT0 pin (or any combina-
tion of these three sources). The comparators may be
used to monitor a voltage input proportional to a current
being monitored in the bridge circuit. If the voltage
exceeds a threshold, the comparator switches state and
triggers a shutdown. Alternatively, a low-level digital sig-
nal on the FLT0 pin can also trigger a shutdown. The
auto-shutdown feature can be disabled by not selecting
any auto-shutdown sources. The auto-shutdown
sources
ECCP1AS2:ECCP1AS0 bits (ECCP1AS<6:4>).
When a shutdown occurs, the output pins are
asynchronously placed in their shutdown states,
specified
PSS1BD1:PSS1BD0 bits (ECCP1AS3:ECCP1AS0).
Each pin pair (P1A/P1C and P1B/P1D) may be set to
drive high, drive low or be tri-stated (not driving). The
ECCP1ASE bit (ECCP1AS<7>) is also set to hold the
Enhanced PWM outputs in their shutdown states.
The ECCP1ASE bit is set by hardware when a
shutdown event occurs. If automatic restarts are not
enabled, the ECCP1ASE bit is cleared by firmware
when the cause of the shutdown clears. If automatic
restarts are enabled, the ECCP1ASE bit is automati-
cally cleared when the cause of the auto-shutdown has
cleared.
If the ECCP1ASE bit is set when a PWM period begins,
the PWM outputs remain in their shutdown state for that
entire PWM period. When the ECCP1ASE bit is
cleared, the PWM outputs will return to normal
operation at the beginning of the next PWM period.
Note:
to
ENHANCED PWM
AUTO-SHUTDOWN
Writing to the ECCP1ASE bit is disabled
while a shutdown condition is active.
by
be
the
used
PSS1AC1:PSS1AC0
are
selected
DS39778D-page 217
using
and
the