參數(shù)資料
型號: PIC18LF2431-I/SO
廠商: Microchip Technology
文件頁數(shù): 41/119頁
文件大?。?/td> 0K
描述: IC MCU FLASH 8KX16 28SOIC
產品培訓模塊: Asynchronous Stimulus
8-bit PIC® Microcontroller Portfolio
標準包裝: 27
系列: PIC® 18F
核心處理器: PIC
芯體尺寸: 8-位
速度: 40MHz
連通性: I²C,SPI,UART/USART
外圍設備: 欠壓檢測/復位,LVD,電源控制 PWM,QEI,POR,PWM,WDT
輸入/輸出數(shù): 24
程序存儲器容量: 16KB(8K x 16)
程序存儲器類型: 閃存
EEPROM 大?。?/td> 256 x 8
RAM 容量: 768 x 8
電壓 - 電源 (Vcc/Vdd): 2 V ~ 5.5 V
數(shù)據(jù)轉換器: A/D 5x10b
振蕩器型: 內部
工作溫度: -40°C ~ 85°C
封裝/外殼: 28-SOIC(0.295",7.50mm 寬)
包裝: 管件
產品目錄頁面: 645 (CN2011-ZH PDF)
PIC18F2331/2431/4331/4431
DS39616D-page 28
2010 Microchip Technology Inc.
2.5
External Oscillator Pins
Many microcontrollers have options for at least two
oscillators: a high-frequency primary oscillator and a
low-frequency
secondary
oscillator
(refer
to
for details).
The oscillator circuit should be placed on the same
side of the board as the device. Place the oscillator
circuit close to the respective oscillator pins with no
more than 0.5 inch (12 mm) between the circuit
components and the pins. The load capacitors should
be placed next to the oscillator itself, on the same side
of the board.
Use a grounded copper pour around the oscillator cir-
cuit to isolate it from surrounding circuits. The
grounded copper pour should be routed directly to the
MCU ground. Do not run any signal traces or power
traces inside the ground pour. Also, if using a two-sided
board, avoid any traces on the other side of the board
where the crystal is placed.
Layout suggestions are shown in Figure 2-4. In-line
packages may be handled with a single-sided layout
that completely encompasses the oscillator pins. With
fine-pitch packages, it is not always possible to com-
pletely surround the pins and components. A suitable
solution is to tie the broken guard sections to a mirrored
ground layer. In all cases, the guard trace(s) must be
returned to ground.
In planning the application’s routing and I/O assign-
ments, ensure that adjacent port pins and other signals
in close proximity to the oscillator are benign (i.e., free
of high frequencies, short rise and fall times, and other
similar noise).
For additional information and design guidance on
oscillator circuits, please refer to these Microchip
Application Notes, available at the corporate web site
(www.microchip.com):
AN826, “Crystal Oscillator Basics and Crystal
Selection for rfPIC and PICmicro Devices”
AN849, “Basic PICmicro Oscillator Design”
AN943, “Practical PICmicro Oscillator Analysis
and Design”
AN949, “Making Your Oscillator Work”
2.6
Unused I/Os
Unused I/O pins should be configured as outputs and
driven to a logic low state. Alternatively, connect a 1 k
to 10 k resistor to VSS on unused pins and drive the
output to logic low.
FIGURE 2-3:
SUGGESTED PLACEMENT
OF THE OSCILLATOR
CIRCUIT
GND
`
OSC1
OSC2
T1OSO
T1OS I
Copper Pour
Primary Oscillator
Crystal
Timer1 Oscillator
Crystal
DEVICE PINS
Primary
Oscillator
C1
C2
T1 Oscillator: C1
T1 Oscillator: C2
(tied to ground)
Single-Sided and In-Line Layouts:
Fine-Pitch (Dual-Sided) Layouts:
GND
OSCO
OSCI
Bottom Layer
Copper Pour
Oscillator
Crystal
Top Layer Copper Pour
C2
C1
DEVICE PINS
(tied to ground)
相關PDF資料
PDF描述
AT87C52X2-SLSUL IC 8051 MCU 8K OTP 30MHZ 44PLCC
PIC32MX420F032H-40V/PT IC MCU 32BIT 32KB FLASH 64TQFP
PIC32MX320F064H-40V/PT IC MCU 32BIT 64KB FLASH 64TQFP
DSPIC33FJ64GP306A-I/PT IC DSPIC MCU/DSP 64K 64-TQFP
AT87C52X2-RLTUM IC 8051 MCU 8K OTP 40MHZ 44VQFP
相關代理商/技術參數(shù)
參數(shù)描述
PIC18LF2431T-I/ML 功能描述:8位微控制器 -MCU 16KB 768 RAM 22I/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
PIC18LF2431T-I/MM 功能描述:8位微控制器 -MCU 16 KB 768 RAM 22 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
PIC18LF2431T-I/SO 功能描述:8位微控制器 -MCU 16KB 768 RAM 22I/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
PIC18LF2439-I/SO 功能描述:8位微控制器 -MCU 12KB 640 RAM 21I/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
PIC18LF2439-I/SP 功能描述:8位微控制器 -MCU 12KB 640 RAM 21I/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