PIC16F72-I/SP Microchip Technology Inc., PIC16F72-I/SP Datasheet - Page 63

• Manufacturer Part Number: PIC16F72-I/SP
• Description: 28 PIN, 3.5 KB FLASH, 128 RAM, 22 I/O
• Manufacturer: Microchip Technology Inc.

Specifications of PIC16F72-I/SP

• A/d Inputs: 5-Channel, 8-Bit
• Cpu Speed: 5 MIPS
• Eeprom Memory: 0 Bytes
• Input Output: 22
• Interface: I2C/SPI
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 28-pin SPDIP
• Programmable Memory: 3.5K Bytes
• Ram Size: 128 Bytes
• Speed: 20 MHz
• Timers: 2-8-bit, 1-16-bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

11.2
11.2.1
The PIC16F72 can be operated in four different Oscil-
lator modes. The user can program two configuration
bits (FOSC1 and FOSC0) to select one of these four
modes:
• LP
• XT
• HS
• RC
11.2.2
In XT, LP or HS modes, a crystal or ceramic resonator
is connected to the OSC1/CLKI and OSC2/CLKO pins
to establish oscillation (Figure 11-1). The PIC16F72
oscillator design requires the use of a parallel cut crys-
tal. Use of a series cut crystal may give a frequency out
of the crystal manufacturers specifications. When in HS
mode, the device can accept an external clock source
to drive the OSC1/CLKI pin (Figure 11-2). See
Figure 14-1 or Figure 14-2 (depending on the part
number and V
frequencies.
FIGURE 11-1:
 2002 Microchip Technology Inc.
Note 1: See Table 11-1 and Table 11-2 for typical
C1
C2(1)
Oscillator Configurations
(1)
2: A series resistor (RS) may be required for
3: RF varies with the crystal chosen.
Low Power Crystal
Crystal/Resonator
High Speed Crystal/Resonator
Resistor/Capacitor
CRYSTAL OSCILLATOR/CERAMIC
RESONATORS
OSCILLATOR TYPES
values of C1 and C2.
AT strip cut crystals.
XTAL
RS
DD
(2)
OSC1
OSC2
range) for valid external clock
CRYSTAL/CERAMIC
RESONATOR OPERATION
(HS, XT OR LP
OSC CONFIGURATION)
RF(3)
PIC16F72
SLEEP
To
internal
logic
FIGURE 11-2:
TABLE 11-1:
Capacitor values are for design guidance only.
These capacitors were tested with the resonators
listed below for basic start-up and operation. These
values were not optimized.
Different capacitor values may be required to produce
acceptable oscillator operation. The user should test
the performance of the oscillator over the expected
V
See the notes at the bottom of page 62 for additional
information.
DD
Clock from
Ext. System
Mode
HS
XT
and temperature range for the application.
Typical Capacitor Values Used:
16.0 MHz
Open
455 kHz
2.0 MHz
4.0 MHz
8.0 MHz
Freq
CERAMIC RESONATORS
(FOR DESIGN
GUIDANCE ONLY)
EXTERNAL CLOCK INPUT
OPERATION (HS OSC
CONFIGURATION)
OSC1
OSC2
PIC16F72
OSC1
56 pF
47 pF
33 pF
27 pF
22 pF
PIC16F72
(HS Mode)
DS39597B-page 61
OSC2
56 pF
47 pF
33 pF
27 pF
22 pF