PIC16F785-I/P Microchip Technology Inc., PIC16F785-I/P Datasheet - Page 28

• Manufacturer Part Number: PIC16F785-I/P
• Description: MCU, 8-Bit, 2KW Flash, 128 RAM, 18 I/O, DIP-20
• Manufacturer: Microchip Technology Inc.

Specifications of PIC16F785-I/P

• A/d Inputs: 12-Channel, 10-Bit
• Comparators: 2
• Cpu Speed: 5 MIPS
• Eeprom Memory: 256 Bytes
• Input Output: 17
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 20-pin PDIP
• 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

PIC16F785/HV785
TABLE 3-3:
3.3.4
The External Resistor-Capacitor (RC) modes support
the use of an external RC circuit. This allows the
designer maximum flexibility in frequency choice while
keeping costs to a minimum when clock accuracy is not
required. There are two modes, RC and RCIO.
In RC mode, the RC circuit connects to the OSC1 pin.
The OSC2/CLKOUT pin outputs the RC oscillator
frequency divided by 4. This signal may be used to
provide a clock for external circuitry, synchronization,
calibration, test or other application requirements.
Figure 3-5 shows the RC mode connections.
FIGURE 3-5:
DS41249D-page 26
LP
XT
HS
Recommended values: 3 k
R
C
Osc Type
Note:
V
EXT
EXT
Note 1: Higher capacitance increases the stability
SS
V
DD
2: Since each resonator/crystal has its own
3: RS may be required to avoid overdriving
These values are for design guidance
only. See notes following this table.
EXTERNAL RC MODES
of the oscillator, but also increases the
start-up time.
characteristics, the user should consult
the resonator/crystal manufacturer for
appropriate
components.
crystals with low drive level specification.
200 kHz
20 MHz
Crystal
F
32 kHz
1 MHz
4 MHz
4 MHz
8 MHz
Freq.
OSC
CAPACITOR SELECTION FOR
CRYSTAL OSCILLATOR
/4
10 k
C
OSC1
OSC2/CLKOUT
RC MODE
EXT
Cap. Range
> 20 pF
15-33 pF
47-68 pF
15-33 pF
15-33 pF
15-33 pF
15-33 pF
15-33 pF
values
R
R
EXT
EXT
C1
PIC16F785/HV785
100 k (V
100 k (V
of
Cap. Range
15-33 pF
47-68 pF
15-33 pF
15-33 pF
15-33 pF
15-33 pF
15-33 pF
Internal
Clock
DD
DD
external
C2
3.0V)
3.0V)
Preliminary
In RCIO mode, the RC circuit is connected to the OSC1
pin. The OSC2 pin becomes an additional general
purpose I/O pin. The I/O pin becomes bit 4 of PORTA
(RA4). Figure 3-6 shows the RCIO mode connections.
FIGURE 3-6:
The RC oscillator frequency is a function of the supply
voltage, the resistor (R
values and the operating temperature. In addition to
this, the oscillator frequency will vary from unit-to-unit
due to normal threshold voltage. Furthermore, the dif-
ference in lead frame capacitance between package
types will also affect the oscillation frequency or low
C
variation due to tolerance of external RC components
used.
C
Recommended values: 3 k
EXT
R
V
EXT
EXT
SS
V
values. The user also needs to take into account
DD
RA4
RCIO MODE
OSC1
10 k
C
I/O (OSC2)
© 2006 Microchip Technology Inc.
EXT
EXT
> 20 pF
R
) and capacitor (C
R
EXT
EXT
PIC16F785/HV785
100 k (V
100 k (V
Internal
Clock
DD
DD
3.0V)
3.0V)
EXT
)