PIC18LF25J11-I/SO Microchip Technology, PIC18LF25J11-I/SO Datasheet - Page 383

• Manufacturer Part Number: PIC18LF25J11-I/SO
• Description: IC PIC MCU FLASH 32K 2V 28-SOIC
• Manufacturer: Microchip Technology
• Series: PIC® XLP™ 18Fr

Specifications of PIC18LF25J11-I/SO

• Core Size: 8-Bit
• Program Memory Size: 32KB (16K x 16)
• Oscillator Type: Internal
• Core Processor: PIC
• Speed: 48MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 16
• Program Memory Type: FLASH
• Ram Size: 3.8K x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 3.6 V
• Data Converters: A/D 10x10b
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-SOIC (7.5mm Width)
• Controller Family/series: PIC18
• No. Of I/o's: 16
• Ram Memory Size: 3776Byte
• Cpu Speed: 48MHz
• No. Of Timers: 5
• No. Of Pwm: RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

24.5
Time can be precisely measured after the ratio (C/I) is
measured from the current and capacitance calibration
step by following these steps:
1.
2.
3.
4.
5.
FIGURE 24-3:
© 2009 Microchip Technology Inc.
Initialize the A/D Converter and the CTMU.
Set EDG1STAT.
Set EDG2STAT.
Perform an A/D conversion.
Calculate the time between edges as T = (C/I) * V,
where I is calculated in the current calibration step
(Section 24.3.1 “Current Source Calibration”),
C is calculated in the capacitance calibration step
(Section 24.3.2 “Capacitance Calibration”) and
V is measured by performing the A/D conversion.
Measuring Time with the CTMU
Module
TYPICAL CONNECTIONS AND INTERNAL CONFIGURATION FOR TIME
MEASUREMENT
CTEDG1
CTEDG2
AN
R
PR
X
EDG2
PIC18F46J11 Device
EDG1
C
AD
A/D Converter
Current Source
CTMU
PIC18F46J11 FAMILY
Output Pulse
It is assumed that the time measured is small enough
that the capacitance, C
to the A/D Converter. For the smallest time measure-
ment, always set the A/D Channel Select register
(AD1CHS) to an unused A/D channel; the correspond-
ing pin for which is not connected to any circuit board
trace. This minimizes added stray capacitance, keep-
ing the total circuit capacitance close to that of the A/D
Converter itself (4-5 pF). To measure longer time
intervals, an external capacitor may be connected to an
A/D channel and this channel selected when making a
time measurement.
OFFSET
, provides a valid voltage
DS39932C-page 383