PIC18F45K20-I/ML Microchip Technology, PIC18F45K20-I/ML Datasheet - Page 58

• Manufacturer Part Number: PIC18F45K20-I/ML
• Description: IC PIC MCU FLASH 16KX16 44QFN
• Manufacturer: Microchip Technology
• Series: PIC® XLP™ 18Fr

Specifications of PIC18F45K20-I/ML

• Program Memory Type: FLASH
• Program Memory Size: 32KB (16K x 16)
• Package / Case: 44-QFN
• 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
• Eeprom Size: 256 x 8
• Ram Size: 1.5K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 3.6 V
• Data Converters: A/D 14x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC18F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 1.5 KB
• Interface Type: CCP/ECCP/EUSART/I2C/MSSP/SPI
• Maximum Clock Frequency: 64 MHz
• Number Of Programmable I/os: 36
• Number Of Timers: 4
• 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
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 14-ch x 10-bit
• Package: 44QFN EP
• Device Core: PIC
• Family Name: PIC18
• Maximum Speed: 64 MHz
• Operating Supply Voltage: 2.5|3.3 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: DM240313 - BOARD DEMO 8BIT XLPAC164112 - VOLTAGE LIMITER MPLAB ICD2 VPPDM164124 - KIT STARTER FOR PIC18F4XK20AC164322 - MODULE SOCKET MPLAB PM3 28/44QFN
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

PICkit™ 3 Debug Express
3.9
FIGURE 3-45:
DS41370C-page 54
LESSON 9: INTERNAL OSCILLATOR
Using the on-chip internal oscillator and PLL (Phase Locked Loop) of the
PIC18F45K20 is discussed. Clocks from 31 kHz up to 64 MHz can be generated
without requiring external oscillator components.
3.9.1
The internal oscillator block of the PIC18F45K20 generates two different clock signals.
The main output, INTOSC, is a factory calibrated 16 MHz clock source with postscaler
that can provide a range of clock frequencies down to 31 kHz.
The other output, INTRC, is a nominal 31 kHz clock source that drives peripherals such
as the Power-up Timer, the Fail-Safe Clock Monitor, the Watchdog Timer and the
Two-Speed Start-up feature.
When the oscillator block is set to provide a 31 kHz clock to the microcontroller, it can
be selected as a postscaled output of INTOSC, which has the benefit of calibrated
accuracy, or INTRC, which has the benefit of lower power consumption.
The oscillator block also contains a 4x PLL (Phase Locked Loop) frequency multiplier
that can increase the microcontroller clock source up to 32 MHz. The PLL is only
available when the internal oscillator block selected output is 8 MHz or 16 MHz. It will
multiply the base 4 MHz signal by 4 to 32 MHz, and the 8 MHz base clock to 64 MHz.
This allows the internal oscillator block to provide a range of 10 different software
selectable frequencies of 31 kHz, 250 kHz, 500 kHz, 1 MHz, 2 MHz, 4MHz, 8 MHz, 16
MHz and (with the PLL) 32 MHz and 64 MHz. Recall from previous lessons that the
default frequency on a Reset is 1 MHz.
SIMPLIFIED INTERNAL OSCILLATOR BLOCK DIAGRAM
Key Concepts
- To use the internal oscillator block, set the OSC Configuration bits to
- The OSCCON Special Function Register is used to set the base internal
- The OSCTUNE register allows the internal oscillator frequency to be
- The 4x PLL may only be used when base frequencies of 8 MHz or 16 MHz
INTIO67 or INTIO7. The latter outputs the clock signal CLKO on the RA6
pin.
oscillator frequency from 31 kHZ up to 16 MHz.
adjusted on a fine scale and enables or disables the PLL.
are selected in OSCCON. Enabling the PLL multiplies the base frequency by
4, providing clocks at 32 MHz and 64 MHz, respectively.
The Internal Oscillator Block
© 2009 Microchip Technology Inc.