PIC16F1947-I/PT Microchip Technology Inc., PIC16F1947-I/PT Datasheet - Page 63

• Manufacturer Part Number: PIC16F1947-I/PT
• Description: 64 TQFP 10x10x1mm TRAY28KB Flash, 1KB RAM, 256B EEPROM, LCD, 1.8-5.5V
• Manufacturer: Microchip Technology Inc.

Specifications of PIC16F1947-I/PT

• A/d Inputs: 17-Channel, 10-Bit
• Comparators: 3
• Cpu Speed: 8 MIPS
• Eeprom Memory: 256 Bytes
• Input Output: 54
• Interface: CAN/I2C/SPI/UART/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 64-pin TQFP
• Programmable Memory: 28K Bytes
• Ram Size: 1K Bytes
• Speed: 32 MHz
• Timers: 4-8-bit, 1-16-bit
• Voltage, Range: 1.8-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

5.2
Clock sources can be classified as external or internal.
External clock sources rely on external circuitry for the
clock source to function. Examples are: oscillator mod-
ules (EC mode), quartz crystal resonators or ceramic
resonators (LP, XT and HS modes) and Resis-
tor-Capacitor (RC) mode circuits.
Internal clock sources are contained internally within
the oscillator module. The internal oscillator block has
two
phase-locked-loop (HFPLL) that are used to generate
three internal system clock sources: the 16 MHz
High-Frequency Internal Oscillator (HFINTOSC), 500
kHZ (MFINTOSC) and the 31 kHz Low-Frequency
Internal Oscillator (LFINTOSC).
The system clock can be selected between external or
internal clock sources via the System Clock Select
(SCS) bits in the OSCCON register. See
“Clock Switching”
5.2.1
An external clock source can be used as the device
system clock by performing one of the following
actions:
• Program the FOSC<2:0> bits in the Configuration
• Write the SCS<1:0> bits in the OSCCON register
See
tion.
5.2.1.1
The External Clock (EC) mode allows an externally
generated logic level signal to be the system clock
source. When operating in this mode, an external clock
source
OSC2/CLKOUT is available for general purpose I/O or
CLKOUT.
mode.
EC mode has 3 power modes to select from through
Configuration Word 1:
• High-power, 4-32 MHz (FOSC = 111)
• Medium power, 0.5-4 MHz (FOSC = 110)
• Low-power, 0-0.5 MHz (FOSC = 101)
 2010 Microchip Technology Inc.
Word 1 to select an external clock source that will
be used as the default system clock upon a
device Reset.
to switch the system clock source to:
- Timer1 Oscillator during run-time, or
- An external clock source determined by the
value of the FOSC bits.
Section 5.3 “Clock
internal
Clock Source Types
is
Figure 5-2
EXTERNAL CLOCK SOURCES
EC Mode
connected
oscillators
for additional information.
shows the pin connections for EC
Switching”for more informa-
to
and
the
a
OSC1
Section 5.3
dedicated
input.
Preliminary
The Oscillator Start-up Timer (OST) is disabled when
EC mode is selected. Therefore, there is no delay in
operation after a Power-on Reset (POR) or wake-up
from Sleep. Because the PIC
static, stopping the external clock input will have the
effect of halting the device while leaving all data intact.
Upon restarting the external clock, the device will
resume operation as if no time had elapsed.
FIGURE 5-2:
5.2.1.2
The LP, XT and HS modes support the use of quartz
crystal resonators or ceramic resonators connected to
OSC1 and OSC2
a low, medium or high gain setting of the internal
inverter-amplifier to support various resonator types
and speed.
LP Oscillator mode selects the lowest gain setting of the
internal inverter-amplifier. LP mode current consumption
is the least of the three modes. This mode is designed to
drive only 32.768 kHz tuning-fork type crystals (watch
crystals).
XT Oscillator mode selects the intermediate gain
setting of the internal inverter-amplifier. XT mode
current consumption is the medium of the three modes.
This mode is best suited to drive resonators with a
medium drive level specification.
HS Oscillator mode selects the highest gain setting of the
internal inverter-amplifier. HS mode current consumption
is the highest of the three modes. This mode is best
suited for resonators that require a high drive setting.
Figure 5-3
quartz crystal and ceramic resonators, respectively.
Note 1:
Clock from
Ext. System
F
OSC
PIC16F/LF1946/47
/4 or I/O
and
Output depends upon CLKOUTEN bit of the
Configuration Word 1.
LP, XT, HS Modes
Figure 5-4
(1)
(Figure
EXTERNAL CLOCK (EC)
MODE OPERATION
5-3). The three modes select
OSC1/CLKIN
OSC2/CLKOUT
show typical circuits for
®
MCU design is fully
PIC
DS41414B-page 63
®
MCU