參數(shù)資料
型號: PIC18LF458T-I/L
廠商: Microchip Technology
文件頁數(shù): 24/116頁
文件大?。?/td> 0K
描述: IC MCU FLSH 16KX16 LV CAN 44PLCC
標(biāo)準(zhǔn)包裝: 500
系列: PIC® 18F
核心處理器: PIC
芯體尺寸: 8-位
速度: 40MHz
連通性: CAN,I²C,SPI,UART/USART
外圍設(shè)備: 欠壓檢測/復(fù)位,LVD,POR,PWM,WDT
輸入/輸出數(shù): 33
程序存儲器容量: 32KB(16K x 16)
程序存儲器類型: 閃存
EEPROM 大?。?/td> 256 x 8
RAM 容量: 1.5K x 8
電壓 - 電源 (Vcc/Vdd): 2 V ~ 5.5 V
數(shù)據(jù)轉(zhuǎn)換器: A/D 8x10b
振蕩器型: 外部
工作溫度: -40°C ~ 85°C
封裝/外殼: 44-LCC(J 形引線)
包裝: 帶卷 (TR)
2006 Microchip Technology Inc.
DS41159E-page 21
PIC18FXX8
2.6.2
OSCILLATOR TRANSITIONS
The PIC18FXX8 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.
Figure 2-7 shows a timing diagram indicating the tran-
sition from the main oscillator to the Timer1 oscillator.
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.
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), 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 2-8.
FIGURE 2-7:
TIMING DIAGRAM FOR TRANSITION FROM OSC1 TO TIMER1 OSCILLATOR
FIGURE 2-8:
TIMING DIAGRAM 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
13
4
5
6
7
8
Q3
Q4
Q1 Q2 Q3 Q4
Q1 Q2
OSC1
Internal System
SCS
(OSCCON<0>)
Program
PC
PC + 2
Note 1: TOST = 1024 TOSC (drawing not to scale).
T1OSI
Clock
OSC2
TOST
Q1
PC + 4
TT1P
TOSC
TSCS
12
3
4
5
6
7
8
Counter
相關(guān)PDF資料
PDF描述
PIC16F627-04E/P IC MCU FLASH 1KX14 18-DIP
PIC16F627-20E/P IC MCU FLASH 1KX14 18-DIP
PIC16C54C-20I/P IC MCU OTP 512X12 18DIP
PIC16F627T-04E/SO IC MCU FLASH 1KX14 18-SOIC
PIC18LF448-I/L IC PIC MCU FLASH 8KX16 44PLCC
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
PIC18LF45J10-I/ML 功能描述:8位微控制器 -MCU 32 KB FL 1024 RAM 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(fēng)格:SMD/SMT
PIC18LF45J10-I/P 功能描述:8位微控制器 -MCU 32KB FL 1024 RAM 32 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(fēng)格:SMD/SMT
PIC18LF45J10-I/PT 功能描述:8位微控制器 -MCU 32 KB FL 1024 RAM 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(fēng)格:SMD/SMT
PIC18LF45J10T-I/ML 功能描述:8位微控制器 -MCU 32 KB FL 1024 RAM 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(fēng)格:SMD/SMT
PIC18LF45J10T-I/PT 功能描述:8位微控制器 -MCU 32 KB FL 1024 RAM 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(fēng)格:SMD/SMT