PIC18F45J50-I/PT Microchip Technology, PIC18F45J50-I/PT Datasheet - Page 407

• Manufacturer Part Number: PIC18F45J50-I/PT
• Description: IC PIC MCU FLASH 32K 2V 44-TQFP
• Manufacturer: Microchip Technology
• Series: PIC® XLP™ 18Fr

Specifications of PIC18F45J50-I/PT

• Program Memory Type: FLASH
• Program Memory Size: 32KB (16K x 16)
• Package / Case: 44-TQFP, 44-VQFP
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 48MHz
• Connectivity: I²C, SPI, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, DMA, POR, PWM, WDT
• Number Of I /o: 34
• Ram Size: 3.8K x 8
• Voltage - Supply (vcc/vdd): 2.15 V ~ 3.6 V
• Data Converters: A/D 13x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC18F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 4 KB
• Interface Type: EUSART, I2C, SPI
• Maximum Clock Frequency: 48 MHz
• Number Of Timers: 5
• Operating Supply Voltage: 2.25 V to 2.75 V
• 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, DV164136, DM183032, MA180024, DM183022
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 13 Channel
• Controller Family/series: PIC18
• No. Of I/o's: 22
• Ram Memory Size: 3776Byte
• Cpu Speed: 48MHz
• No. Of Timers: 5
• Embedded Interface Type: EUSART, I2C, SPI
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: AC164322 - MODULE SOCKET MPLAB PM3 28/44QFN
• Eeprom Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

25.5
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 25-3:
© 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 25.3.1 “Current Source Calibration”),
C is calculated in the capacitance calibration step
(Section 25.3.2 “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
PIC18F46J50 Device
EDG1
C
AD
A/D Converter
Current Source
CTMU
PIC18F46J50 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,
keeping 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
DS39931C-page 407