參數(shù)資料
型號: PIC18LF6620-I/PT
廠商: Microchip Technology
文件頁數(shù): 87/165頁
文件大?。?/td> 0K
描述: IC MCU FLSH 1MBIT W/AD LP 64TQFP
產(chǎn)品培訓模塊: Asynchronous Stimulus
標準包裝: 160
系列: PIC® 18F
核心處理器: PIC
芯體尺寸: 8-位
速度: 25MHz
連通性: I²C,SPI,UART/USART
外圍設(shè)備: 欠壓檢測/復位,LVD,POR,PWM,WDT
輸入/輸出數(shù): 52
程序存儲器容量: 64KB(32K x 16)
程序存儲器類型: 閃存
EEPROM 大?。?/td> 1K x 8
RAM 容量: 3.75K x 8
電壓 - 電源 (Vcc/Vdd): 2 V ~ 5.5 V
數(shù)據(jù)轉(zhuǎn)換器: A/D 12x10b
振蕩器型: 外部
工作溫度: -40°C ~ 85°C
封裝/外殼: 64-TQFP
包裝: 托盤
PIC18F6520/8520/6620/8620/6720/8720
DS39609B-page 26
2004 Microchip Technology Inc.
2.6.2
OSCILLATOR TRANSITIONS
PIC18FXX20 devices contain circuitry to prevent
“glitches” when switching between oscillator sources.
Essentially, the circuitry waits for eight rising edges of
the clock source that the processor is switching to. This
ensures that the new clock source is stable and that its
pulse width will not be less than the shortest pulse
width of the two clock sources.
A timing diagram indicating the transition from the main
oscillator to the Timer1 oscillator is shown in Figure 2-8.
The Timer1 oscillator is assumed to be running all the
time. After the SCS bit is set, the processor is frozen at
the next occurring Q1 cycle. After eight synchronization
cycles are counted from the Timer1 oscillator, operation
resumes. No additional delays are required after the
synchronization cycles.
FIGURE 2-8:
TIMING DIAGRAM FOR TRANSITION FROM OSC1 TO TIMER1 OSCILLATOR
The sequence of events that takes place when switch-
ing from the Timer1 oscillator to the main oscillator will
depend on the mode of the main oscillator. In addition
to eight clock cycles of the main oscillator, additional
delays may take place.
If the main oscillator is configured for an external
crystal (HS, XT, LP), then the transition will take place
after an oscillator start-up time (TOST) has occurred. A
timing diagram, indicating the transition from the
Timer1 oscillator to the main oscillator for HS, XT and
LP modes, is shown in Figure 2-9.
FIGURE 2-9:
TIMING FOR TRANSITION BETWEEN TIMER1 AND OSC1 (HS, XT, LP)
Q3
Q2
Q1
Q4
Q3
Q2
OSC1
Internal
SCS
(OSCCON<0>)
Program
PC + 2
PC
Note 1: Delay on internal system clock is eight oscillator cycles for synchronization.
Q1
T1OSI
Q4
Q1
PC + 4
Q1
TSCS
Clock
Counter
System
Q2
Q3
Q4
Q1
TDLY
TT1P
TOSC
2
1
3
4
5678
Q3
Q4
Q1
Q2
Q3
Q4
Q1
Q2
OSC1
Internal
SCS
(OSCCON<0>)
Program
PC
PC + 2
Note 1: TOST = 1024 TOSC (drawing not to scale).
T1OSI
System Clock
OSC2
TOST
Q1
PC + 6
TT1P
TOSC
TSCS
12
3
4
5
6
7
8
Counter
相關(guān)PDF資料
PDF描述
65175-002LF BP COVER LF
PIC18F8628-I/PT IC PIC MCU FLASH 48KX16 80TQFP
PIC17C756A-16I/L IC MCU OTP 16KX16 A/D PWM 68PLCC
PIC17C44-33/P IC MCU OTP 8KX16 PWM 40DIP
PIC18LF6628-I/PT IC PIC MCU FLASH 48KX16 64TQFP
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
PIC18LF6620T-I/PT 功能描述:8位微控制器 -MCU 64KB 3840 RAM 52I/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
PIC18LF6621-I/PT 功能描述:8位微控制器 -MCU 64KB 3840 RAM 52I/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
PIC18LF6621-I/PTG 功能描述:8位微控制器 -MCU 64kBF 3840RM 52 I/O Lead Free Package 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
PIC18LF6621T-I/PT 功能描述:8位微控制器 -MCU 64KB 3840 RAM 52I/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
PIC18LF6622-I/PT 功能描述:8位微控制器 -MCU 64 KB FL 4K RAM 70 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