PIC12F635-I/MD Microchip Technology, PIC12F635-I/MD Datasheet - Page 53

• Manufacturer Part Number: PIC12F635-I/MD
• Description: IC PIC MCU FLASH 1KX14 8DFN
• Manufacturer: Microchip Technology
• Series: PIC® 12Fr

Specifications of PIC12F635-I/MD

• Core Size: 8-Bit
• Program Memory Size: 1.75KB (1K x 14)
• Core Processor: PIC
• Speed: 20MHz
• Peripherals: Brown-out Detect/Reset, POR, WDT
• Number Of I /o: 5
• 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 ~ 85°C
• Package / Case: 8-DFN
• Controller Family/series: PIC12
• No. Of I/o's: 6
• Eeprom Memory Size: 128Byte
• Ram Memory Size: 64Byte
• Cpu Speed: 20MHz
• No. Of Timers: 2
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: AC164326 - MODULA SKT PM3 20QFNXLT08DFN2 - SOCKET TRANSITION ICE 14DIP/8DFNAC162057 - MPLAB ICD 2 HEADER 14DIPXLT08DFN - SOCKET TRANSITION ICE 8DFN
• Data Converters: -
• Connectivity: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

4.2.3
The Ultra Low-Power Wake-up (ULPWU) on RA0 allows
a slow falling voltage to generate an interrupt-on-change
on RA0 without excess current consumption. The mode
is selected by setting the ULPWUE bit of the PCON
register. This enables a small current sink which can be
used to discharge a capacitor on RA0.
To use this feature, the RA0 pin is configured to output
‘1’ to charge the capacitor, interrupt-on-change for RA0
is enabled and RA0 is configured as an input. The
ULPWUE bit is set to begin the discharge and a SLEEP
instruction is performed. When the voltage on RA0 drops
below V
the device to wake-up. Depending on the state of the
GIE bit of the INTCON register, the device will either
jump to the interrupt vector (0004h) or execute the next
instruction when the interrupt event occurs. See
Section 4.2.2
Section 12.9.3
information.
This feature provides a low-power technique for
periodically waking up the device from Sleep. The
time-out is dependent on the discharge time of the RC
circuit on RA0. See Example 4-2 for initializing the Ultra
Low Power Wake-up module.
The series resistor provides overcurrent protection for the
RA0 pin and can allow for software calibration of the
time-out (see Figure 4-1). A timer can be used to measure
the charge time and discharge time of the capacitor. The
charge time can then be adjusted to provide the desired
interrupt delay. This technique will compensate for the
affects of temperature, voltage and component accuracy.
The Ultra Low-Power Wake-up peripheral can also be
configured as a simple Programmable Low-Voltage
Detect or temperature sensor.
© 2007 Microchip Technology Inc.
Note:
IL
, an interrupt will be generated which will cause
ULTRA LOW-POWER WAKE-UP
For more information, refer to the
Application Note AN879, “Using the
Microchip Ultra Low-Power Wake-up
Module” (DS00879).
“PORTA
“Interrupt-on-Change”
Interrupt”
for
more
PIC12F635/PIC16F636/639
and
EXAMPLE 4-2:
BANKSEL PORTA
BSF
MOVLW
MOVWF
BANKSEL TRISA
BCF
CALL
BSF
BSF
BSF
MOVLW
MOVWF
SLEEP
NOP
PORTA,0
H’7’
CMCON0
TRISA,0
CapDelay
PCON,ULPWUE ;Enable ULP Wake-up
IOCA,0
TRISA,0
B’10001000’ ;Enable interrupt
INTCON
ULTRA LOW-POWER
WAKE-UP INITIALIZATION
;
;Set RA0 data latch
;Turn off
; comparators
;
;Output high to
; charge capacitor
;Select RA0 IOC
;RA0 to input
; and clear flag
;Wait for IOC
;
DS41232D-page 51