参数资料
型号: AT89C51RB2-SLRIL
厂商: Atmel
文件页数: 33/127页
文件大小: 0K
描述: IC MCU FLASH 8051 16K 3V 44-PLCC
标准包装: 1
系列: 89C
核心处理器: 8051
芯体尺寸: 8-位
速度: 40MHz
连通性: SPI,UART/USART
外围设备: POR,PWM,WDT
输入/输出数: 32
程序存储器容量: 16KB(16K x 8)
程序存储器类型: 闪存
RAM 容量: 1.25K x 8
电压 - 电源 (Vcc/Vdd): 2.7 V ~ 3.6 V
振荡器型: 外部
工作温度: -40°C ~ 85°C
封装/外壳: 44-LCC(J 形引线)
包装: 剪切带 (CT)
配用: AT89STK-11-ND - KIT STARTER FOR AT89C51RX2
其它名称: AT89C51RB2SLRILCT
13
AT89C51RB2/RC2
4180E–8051–10/06
Port Types
AT89C51RB2/RC2 I/O ports (P1, P2, P3) implement the quasi-bidirectional output that
is common on the 80C51 and most of its derivatives. This output type can be used as
both an input and output without the need to reconfigure the port. This is possible
because when the port outputs a logic high, it is weakly driven, allowing an external
device to pull the pin low. When the pin is pulled low, it is driven strongly and able to sink
a fairly large current. These features are somewhat similar to an open drain output
except that there are three pull-up transistors in the quasi-bidirectional output that serve
different purposes. One of these pull-ups, called the "weak" pull-up, is turned on when-
ever the port latch for the pin contains a logic 1. The weak pull-up sources a very small
current that will pull the pin high if it is left floating. A second pull-up, called the "medium"
pull-up, is turned on when the port latch for the pin contains a logic 1 and the pin itself is
also at a logic 1 level. This pull-up provides the primary source current for a quasi-bidi-
rectional pin that is outputting a 1. If a pin that has a logic 1 on it is pulled low by an
external device, the medium pull-up turns off, and only the weak pull-up remains on. In
order to pull the pin low under these conditions, the external device has to sink enough
current to overpower the medium pull-up and take the voltage on the port pin below its
input threshold.
The third pull-up is referred to as the "strong" pull-up. This pull-up is used to speed up
low-to-high transitions on a quasi-bidirectional port pin when the port latch changes from
a logic 0 to a logic 1. When this occurs, the strong pull-up turns on for a brief time, two
CPU clocks, in order to pull the port pin high quickly. Then it turns off again.
The DPU bit (bit 7 in AUXR register) allows to disable the permanent weak pull up of all
ports when latch data is logical 0.
The quasi-bidirectional port configuration is shown in Figure 3.
Figure 3. Quasi-Bidirectional Output
2 CPU
Input
Pin
Strong
Medium
N
Weak
P
Clock Delay
Port Latch
Data
DPU
AUXR.7
PP
相关PDF资料
PDF描述
AT89C51ID2-SLRIM IC MCU FLASH 8051 64K 5V 44-PLCC
PIC16C923-04/L IC MCU OTP 4KX14 LCD DVR 68PLCC
PIC18F2423-I/SO IC PIC MCU FLASH 8KX16 28SOIC
PIC16C57-LP/SO IC MCU OTP 2KX12 28SOIC
PIC18LF6410-I/PT IC PIC MCU FLASH 8KX16 64TQFP
相关代理商/技术参数
参数描述
AT89C51RB2-SLRIM 功能描述:IC MCU FLASH 8051 16K 5V 44-PLCC RoHS:否 类别:集成电路 (IC) >> 嵌入式 - 微控制器, 系列:89C 标准包装:1,500 系列:AVR® ATtiny 核心处理器:AVR 芯体尺寸:8-位 速度:16MHz 连通性:I²C,LIN,SPI,UART/USART,USI 外围设备:欠压检测/复位,POR,PWM,温度传感器,WDT 输入/输出数:16 程序存储器容量:8KB(4K x 16) 程序存储器类型:闪存 EEPROM 大小:512 x 8 RAM 容量:512 x 8 电压 - 电源 (Vcc/Vdd):2.7 V ~ 5.5 V 数据转换器:A/D 11x10b 振荡器型:内部 工作温度:-40°C ~ 125°C 封装/外壳:20-SOIC(0.295",7.50mm 宽) 包装:带卷 (TR)
AT89C51RB2-SLRUL 功能描述:8位微控制器 -MCU C51RB2 FLASH 3V 16k Ind RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
AT89C51RB2-SLRUM 功能描述:8位微控制器 -MCU C51RB2 FLASH 5V 16k ind RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
AT89C51RB2-SLSCM 制造商:ATMEL 制造商全称:ATMEL Corporation 功能描述:Microcontroller with 16K/32K Bytes Flash
AT89C51RB2-SLSIL 功能描述:IC 8051 MCU FLASH 16K 44PLCC RoHS:否 类别:集成电路 (IC) >> 嵌入式 - 微控制器, 系列:89C 标准包装:9 系列:87C 核心处理器:8051 芯体尺寸:8-位 速度:40/20MHz 连通性:UART/USART 外围设备:POR,WDT 输入/输出数:32 程序存储器容量:32KB(32K x 8) 程序存储器类型:OTP EEPROM 大小:- RAM 容量:256 x 8 电压 - 电源 (Vcc/Vdd):4.5 V ~ 5.5 V 数据转换器:- 振荡器型:内部 工作温度:0°C ~ 70°C 封装/外壳:40-DIP(0.600",15.24mm) 包装:管件