PIC16F631-E/SS Microchip Technology, PIC16F631-E/SS Datasheet - Page 146

• Manufacturer Part Number: PIC16F631-E/SS
• Description: IC,MICROCONTROLLER,8-BIT,PIC CPU,CMOS,SSOP,20PIN,PLASTIC
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F631-E/SS

• Rohs Compliant: YES
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Peripherals: Brown-out Detect/Reset, POR, WDT
• Number Of I /o: 18
• Program Memory Size: 1.75KB (1K x 14)
• Program Memory Type: FLASH
• Eeprom Size: 128 x 8
• Ram Size: 64 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 20-SSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 658-1047-5 - BOARD EVALUATION ACCESSTOUCHXLT20SS1-1 - SOCKET TRANSITION 20DIP 20SSOPAC162061 - HEADER INTRFC MPLAB ICD2 20PIN
• Data Converters: -
• Connectivity: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

PIC16F631/677/685/687/689/690
11.4.6
In Half-Bridge applications where all power switches
are modulated at the PWM frequency, 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) will flow through both power
switches, shorting the bridge supply. To avoid this
potentially destructive shoot-through current from
flowing during switching, turning on either of the power
switches is normally delayed to allow the other switch
to completely turn off.
In Half-Bridge mode, a digitally programmable
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 11-8 for illustration.
The lower seven bits of the associated PWM1CON
register (Register 11-3) sets the delay period in terms
of microcontroller instruction cycles (T
FIGURE 11-18:
DS41262E-page 144
Standard Half-Bridge Circuit (“Push-Pull”)
PROGRAMMABLE DEAD-BAND
DELAY MODE
EXAMPLE OF HALF-BRIDGE APPLICATIONS
CY
or 4 T
P1A
P1B
OSC
).
FET
Driver
FET
Driver
FIGURE 11-17:
P1A
P1B
td = Dead-Band Delay
Note 1: At this time, the TMR2 register is equal to the
(2)
(2)
V+
V-
(1)
2: Output signals are shown as active-high.
td
Pulse Width
PR2 register.
Load
Period
td
EXAMPLE OF
HALF-BRIDGE PWM
OUTPUT
© 2008 Microchip Technology Inc.
+
V
-
+
V
-
(1)
Period
(1)