參數(shù)資料
型號： PIC16F785
廠商： Microchip Technology Inc.
英文描述： 20-Pin Flash-Based 8-Bit CMOS Microcontroller with Two-Phase Asychronous Feedback PWM, Dual High-Speed Comparators and Dual Operational Amplifiers
中文描述： 20引腳基于閃存的8兩相異步反饋的PWM，雙高位CMOS微控制器的高速比較器和雙運算放大器
文件頁數(shù)： 28/178頁
文件大?。?/td> 1620K
代理商： PIC16F785
PIC16F785
DS41249A-page 26
Preliminary
2004 Microchip Technology Inc.
3.3.4
EXTERNAL RC MODES
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:
RC MODE
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:
RCIO MODE
The RC oscillator frequency is a function of the supply
voltage, the resistor (R
EXT
) and capacitor (C
EXT
)
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
EXT
values. The user also needs to take into account
variation due to tolerance of external RC components
used.
3.4
Internal Clock Modes
The PIC16F785 has two independent, internal
oscillators that can be configured or selected as the
system clock source.
HFINTOSC
(High-frequency
Oscillator) is factory calibrated and operates at
8 MHz. The frequency of the HFINTOSC can be
user adjusted ±12% via software using the
OSCTUNE register (Register 3-1).
2.
The
LFINTOSC
(Low-frequency
Oscillator) is uncalibrated and operates at
approximately 31 kHz.
1.
The
Internal
Internal
The system clock speed can be selected via software
using the Internal Oscillator Frequency Select (IRCF)
bits.
The system clock can be selected between external or
internal clock sources via the System Clock Selection
(SCS) bit (See
Section 3.5 “Clock Switching”
).
3.4.1
INTRC AND INTRCIO MODES
The INTRC and INTRCIO modes configure the internal
oscillators as the system clock source when the device
is programmed using the Oscillator Selection (FOSC)
bits in the Configuration Word (Register 12-1).
In
INTRC
mode, the OSC1 pin is available for general
purpose I/O. The OSC2/CLKOUT pin outputs the
selected internal oscillator frequency divided by 4. The
CLKOUT signal may be used to provide a clock for
external circuitry, synchronization, calibration, test or
other application requirements.
In
INTRCIO
mode, the OSC1 and OSC2 pins are avail-
able for general purpose I/O.
3.4.2
HFINTOSC
The High-frequency Internal Oscillator (HFINTOSC) is
a factory calibrated 8 MHz internal clock source. The
frequency of the HFINTOSC can be altered
approximately ±12% via software using the OSCTUNE
register (Register 3-1).
The output of the HFINTOSC connects to a postscaler
and multiplexer (see Figure 3-1). One of seven
frequencies can be selected via software using the
IRCF bits (see
Section 3.4.4 “Frequency Select Bits
(IRCF)”
).
The HFINTOSC is enabled by selecting any frequency
between 8 MHz and 125 kHz (IRCF
≠
000
) as the sys-
tem clock source (SCS =
1
) or when Two-Speed
Start-up is enabled (IESO =
1
and IRCF
≠
000
).
The HF Internal Oscillator (HTS) bit, (OSCCON<2>),
indicates whether the HFINTOSC is stable or not.
OSC2/CLKOUT
C
EXT
R
EXT
OSC1
F
OSC
/4
Internal
Clock
V
DD
V
SS
Recommended values: 3 k
≤
R
EXT
≤
100 k
(V
DD
≥
3V)
10 k
≤
R
EXT
≤
100 k
(V
DD
<
3V)
C
EXT
> 20 pF
PIC16F785
C
EXT
R
EXT
OSC1
Internal
Clock
V
DD
V
SS
I/O (OSC2)
RA4
PIC16F785
Recommended values: 3 k
≤
R
EXT
≤
100 k
(V
DD
≥
3V)
10 k
≤
R
EXT
≤
100 k
(V
DD
<
3V)
C
EXT
> 20 pF
相關(guān)PDF資料
PDF描述
PIC16F818 18/20-Pin Enhanced FLASH Microcontrollers with nanoWatt Technology(18/20引腳，納瓦技術(shù)增強FLASH微控制器)
PIC16F819 18/20-Pin Enhanced FLASH Microcontrollers with nanoWatt Technology(18/20引腳，納瓦技術(shù)增強FLASH微控制器)
PIC16F83 8-Bit CMOS Flash/EEPROM Microcontollrs(每個I/O口有20mA吸收,25mA驅(qū)動，64字節(jié)數(shù)據(jù)EEPROM，2.0V的微控制器)
PIC16F84 18-pin Flash/EEPROM 8-Bit Microcontrollers
PIC16F85 18/20 Pin, 8-Bit CMOS FLASH Microcontroller with Comparators and A/D Product Brief
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
PIC16F785-E/ML 功能描述:8位微控制器 -MCU 3.5 KB 128 RAM 18I/O RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風格:SMD/SMT
PIC16F785-E/P 功能描述:8位微控制器 -MCU 14KB 368 RAM 33 I/O RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風格:SMD/SMT
PIC16F785-E/SO 功能描述:8位微控制器 -MCU 3.5KB FL 128R 18 I/O RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風格:SMD/SMT
PIC16F785-E/SS 功能描述:8位微控制器 -MCU 3.5KB FL 128R 18 I/O RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風格:SMD/SMT
PIC16F785-I/ML 功能描述:8位微控制器 -MCU 3.5 KB 128 RAM 18I/O RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風格:SMD/SMT
發(fā)布緊急采購，3分鐘左右您將得到回復。

采購需求

(若只采購一條型號，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進入我的后臺，查看報價

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進入我的后臺，查看報價

*型號 *數(shù)量 廠商 批號 封裝
添加更多采購

我的聯(lián)系方式

*
*
*