PIC18F46K22-I/MV Microchip Technology, PIC18F46K22-I/MV Datasheet - Page 327

• Manufacturer Part Number: PIC18F46K22-I/MV
• Description: 64KB, Flash, 3968bytes-RAM,8-bit Family,nanoWatt XLP 40 UQFN 5x5x0.5mm TUBE
• Manufacturer: Microchip Technology
• Series: PIC® XLP™ 18Fr

Specifications of PIC18F46K22-I/MV

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 64MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, HLVD, POR, PWM, WDT
• Number Of I /o: 35
• Program Memory Size: 64KB (32K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 1K x 8
• Ram Size: 3.8K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 30x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 40-UFQFN Exposed Pad
• Processor Series: PIC18F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 4 KB
• Number Of Programmable I/os: 36
• Number Of Timers: 3 x 8-bit. 4 x 16-bit
• Operating Supply Voltage: 1.8 V to 5.5 V
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

19.5
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 19-3:
 2010 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 19.3.1 “Current Source
C is calculated in the capacitance calibration step
(Section 19.3.2 “Capacitance
V is measured by performing the A/D conversion.
Measuring Time with the CTMU
Module
TYPICAL CONNECTIONS AND INTERNAL CONFIGURATION FOR TIME
MEASUREMENT
CTED1
CTED2
AN
R
PR
X
Calibration”) and
Calibration”),
PIC18(L)FXXK22 Device
EDG2
Preliminary
EDG1
C
AD
A/D Converter
Current Source
CTMU
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.
PIC18(L)F2X/4XK22
OFFSET
, provides a valid voltage
DS41412D-page 327