PIC16F1933-ESLASHP datasheet(113/418 Pages) MICROCHIP

113 / 418 page

Preliminary

DS41364A-page 111

PIC16F193X/LF193X

8.4.4

EXTERNAL RC MODE

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.

The RC circuit connects to OSC1. OSC2/CLKOUT is

available for general purpose I/O or CLKOUT.

Figure 8-5 shows the external RC mode connections.

FIGURE 8-5:

EXTERNAL RC MODES

The RC oscillator frequency is a function of the supply

voltage, the resistor (REXT) and capacitor (CEXT) values

and the operating temperature. Other factors affecting

the oscillator frequency are:

• threshold voltage variation

• component tolerances

• packaging variations in capacitance

The user also needs to take into account variation due

to tolerance of external RC components used.

8.5

Internal Clock Modes

The oscillator module has three independent, internal

oscillators that can be configured or selected as the

system clock source.

The

HFINTOSC

(High-Frequency

Internal

Oscillator) is factory calibrated and operates at

16 MHz. The frequency of the HFINTOSC can

user-adjusted

via

software

using

the

OSCTUNE register (Register 8-3).

The MFINTOSC (Medium-Frequency Internal

Oscillator) is factory calibrated and operates at

500 kHz. The frequency of the MFINTOSC can

user-adjusted

via

software

using

the

OSCTUNE register (Register 8-3).

The

LFINTOSC

(Low-Frequency

Internal

Oscillator) is uncalibrated and operates at

31 kHz.

The system clock speed can be selected via software

using the Internal Oscillator Frequency Select bits

IRCF<2:0> of the OSCCON register.

The system clock can be selected between external or

internal clock sources via the System Clock Selection

(SCS) bits of the OSCCON register. See Section 8.6

“Clock Switching” for more information.

8.5.1

INTOSC MODE

The INTOSC mode configures the internal oscillators

as the system clock source when the device is

programmed using the oscillator selection or the

FOSC<2:0> bits in the Configuration Word Register 1

(CONFIG1).

In INTOSC mode, OSC1/CLKIN is available for general

purpose I/O. OSC2/CLKOUT is available for general

purpose I/O or CLKOUT.

OSC2/CLKOUT

CEXT

REXT

PIC® MCU

OSC1/CLKIN

FOSC/4 or

Internal

Clock

VDD

VSS

Recommended values: 10 k

Ω ≤ REXT ≤ 100 kΩ, <3V

3 k

Ω ≤ REXT ≤ 100 kΩ, 3-5V

CEXT > 20 pF, 2-5V

Note

Output depends upon CLKOUTEN bit of the

Configuration Word 1.

I/O(1)

PIC16F1933-E/P Datasheet(PDF) 113 Page - Microchip Technology

PIC16F1933-E/P Datasheet(HTML) 113 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL