PIC18F1220-I/SO Microchip Technology Inc., PIC18F1220-I/SO Datasheet - Page 107

• Manufacturer Part Number: PIC18F1220-I/SO
• Description: Microcontroller; 4 KB Flash; 256 RAM; 256 EEPROM; 16 I/O; 18-Pin-SOIC
• Manufacturer: Microchip Technology Inc.

Specifications of PIC18F1220-I/SO

• A/d Inputs: 7-Channel, 10-Bit
• Cpu Speed: 10 MIPS
• Eeprom Memory: 256 Bytes
• Input Output: 16
• Interface: USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 18-pin SOIC
• Programmable Memory: 4K Bytes
• Ram Size: 256 Bytes
• Speed: 20 MHz
• Timers: 1-8-bit, 3-16-bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

12.2
A crystal oscillator circuit is built-in between pins T1OSI
(input) and T1OSO (amplifier output). It is enabled by
setting control bit, T1OSCEN (T1CON<3>). The oscil-
lator is a low-power oscillator rated for 32 kHz crystals.
It will continue to run during all power managed modes.
The circuit for a typical LP oscillator is shown in
Figure 12-3. Table 12-1 shows the capacitor selection
for the Timer1 oscillator.
The user must provide a software time delay to ensure
proper start-up of the Timer1 oscillator.
 2004 Microchip Technology Inc.
Note:
Timer1 Oscillator
The Timer1 oscillator shares the T1OSI
and T1OSO pins with the PGD and PGC
pins
debugging.
When using the Timer1 oscillator, In-Circuit
Serial Programming (ICSP) may not
function correctly (high voltage or low
voltage), or the In-Circuit Debugger (ICD)
may not communicate with the controller.
As a result of using either ICSP or ICD, the
Timer1 crystal may be damaged.
If ICSP or ICD operations are required, the
crystal should be disconnected from the
circuit (disconnect either lead), or installed
after programming. The oscillator loading
capacitors may remain in-circuit during
ICSP or ICD operation.
used
for
programming
and
FIGURE 12-3:
TABLE 12-1:
Osc Type
Note 1: Microchip suggests this value as a starting
Note:
LP
2: Higher capacitance increases the stability
3: Since each resonator/crystal has its own
4: Capacitor values are for design guidance
PIC18F1220/1320
22 pF
22 pF
C1
C2
point in validating the oscillator circuit.
Oscillator operation should then be tested
to ensure expected performance under
all
temperature).
of the oscillator, but also increases the
start-up time.
characteristics, the user should consult
the resonator/crystal manufacturer for
appropriate
components.
only.
See the Notes with Table 12-1 for additional
information about capacitor selection.
32 kHz
PGD
PGC
expected
32.768 kHz
XTAL
Freq
CAPACITOR SELECTION FOR
THE TIMER OSCILLATOR
EXTERNAL
COMPONENTS FOR THE
TIMER1 LP OSCILLATOR
values
conditions
22 pF
PGD/T1OSI
PGC/T1OSO
C1
PIC18FXXXX
DS39605C-page 105
(1)
of
(V
22 pF
DD
external
C2
(1)
and