参数资料
| 型号： | PCA9674PW,112 |
| 厂商： | NXP Semiconductors |
| 文件页数： | 6/40页 |
| 文件大小： | 0K |
| 描述： | IC I/O EXPANDER I2C 8B 16TSSOP |
| 标准包装： | 96 |
| 接口： | I²C |
| 输入/输出数： | 8 |
| 中断输出： | 是 |
| 频率 - 时钟： | 1MHz |
| 电源电压： | 2.3 V ~ 5.5 V |
| 工作温度： | -40°C ~ 85°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 16-TSSOP（0.173"，4.40mm 宽） |
| 供应商设备封装： | 16-TSSOP |
| 包装： | 管件 |
| 包括： | POR |
| 其它名称： | 935282735112 PCA9674PW PCA9674PW-ND |
第1页第2页第3页第4页第5页当前第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页第37页第38页第39页第40页
PCA9674_PCA9674A
All information provided in this document is subject to legal disclaimers.
NXP B.V. 2013. All rights reserved.
Product data sheet
Rev. 7 — 30 May 2013
14 of 40
NXP Semiconductors
PCA9674; PCA9674A
Remote 8-bit I/O expander for Fm+ I2C-bus with interrupt
8.
I/O programming
8.1 Quasi-bidirectional I/Os
A quasi-bidirectional I/O is an input or output port without using a direction control register.
Whenever the master reads the register, the value returned to master depends on the
actual voltage or status of the pin. At power-on, all the ports are HIGH with a weak 100
A
internal pull-up to VDD, but can be driven LOW by an internal transistor, or an external
signal. The I/O ports are entirely independent of each other, but each I/O octal is
controlled by the same read or write data byte.
Advantages of the quasi-bidirectional I/O over totem pole I/O include:
Better for driving LEDs since the p-channel (transistor to VDD) is small, which saves
die size and therefore cost. LED drive only requires an internal transistor to ground,
while the LED is connected to VDD through a current-limiting resistor. Totem pole I/O
have both n-channel and p-channel transistors, which allow solid HIGH and LOW
output levels without a pull-up resistor — good for logic levels.
Simpler architecture — only a single register and the I/O can be both input and output
at the same time. Totem pole I/O have a direction register that specifies the port pin
direction and it is always in that configuration unless the direction is explicitly
changed.
Does not require a command byte. The simplicity of one register (no need for the
pointer register or, technically, the command byte) is an advantage in some
embedded systems where every byte counts because of memory or bandwidth
limitations.
There is only one register to control four possibilities of the port pin: Input HIGH, input
LOW, output HIGH, or output LOW.
Input HIGH: The master needs to write 1 to the register to set the port as an input mode
if the device is not in the default power-on condition. The master reads the register to
check the input status. If the external source pulls the port pin up to VDD or drives
logic 1, then the master will read the value of 1.
Input LOW: The master needs to write 1 to the register to set the port to input mode if
the device is not in the default power-on condition. The master reads the register to
check the input status. If the external source pulls the port pin down to VSS or drives
logic 0, which sinks the weak 100
A current source, then the master will read the value
of 0.
Output HIGH: The master writes 1 to the register. There is an additional ‘accelerator’ or
strong pull-up current when the master sets the port HIGH. The additional strong pull-up
is only active during the HIGH time of the acknowledge clock cycle. This accelerator
current helps the port’s 100
A current source make a faster rising edge into a heavily
loaded output, but only at the start of the acknowledge clock cycle to avoid bus
contention if an external signal is pulling the port LOW to VSS/driving the port with
logic 0 at the same time. After the half clock cycle there is only the 100
A current
source to hold the port HIGH.
Output LOW: The master writes 0 to the register. There is a strong current sink
transistor that holds the port pin LOW. A large current may flow into the port, which
could potentially damage the part if the master writes a 0 to the register and an external
source is pulling the port HIGH at the same time.
相关PDF资料 |
PDF描述 |
|---|---|
| PCA9554D,118 | IC I/O EXPANDER I2C 8B 16SOIC |
| PCA9554ATS,112 | IC I/O EXPANDER I2C 8B 20SSOP |
| PCA9554AD,118 | IC I/O EXPANDER I2C 8B 16SOIC |
| PCA9674APW,112 | IC I/O EXPANDER I2C 8B 16TSSOP |
| PCA9670BS,118 | IC I/O EXPANDER I2C 8B 16HVQFN |
相关代理商/技术参数 |
参数描述 |
|---|---|
| PCA9674PW-T | 功能描述:接口-I/O扩展器 8-BIT I2C FM+ QB GPIO INT PU RoHS:否 制造商:NXP Semiconductors 逻辑系列: 输入/输出端数量: 最大工作频率:100 kHz 工作电源电压:1.65 V to 5.5 V 工作温度范围:- 40 C to + 85 C 安装风格:SMD/SMT 封装 / 箱体:HVQFN-16 封装:Reel |
| PCA9674TS | 功能描述:接口-I/O扩展器 8-BIT I2C FM+ QB GPIO INT PU RoHS:否 制造商:NXP Semiconductors 逻辑系列: 输入/输出端数量: 最大工作频率:100 kHz 工作电源电压:1.65 V to 5.5 V 工作温度范围:- 40 C to + 85 C 安装风格:SMD/SMT 封装 / 箱体:HVQFN-16 封装:Reel |
| PCA9674TS,112 | 功能描述:接口-I/O扩展器 8-BIT I2C FM+ QB RoHS:否 制造商:NXP Semiconductors 逻辑系列: 输入/输出端数量: 最大工作频率:100 kHz 工作电源电压:1.65 V to 5.5 V 工作温度范围:- 40 C to + 85 C 安装风格:SMD/SMT 封装 / 箱体:HVQFN-16 封装:Reel |
| PCA9674TS,118 | 功能描述:接口-I/O扩展器 8-BIT I2C FM+ QB RoHS:否 制造商:NXP Semiconductors 逻辑系列: 输入/输出端数量: 最大工作频率:100 kHz 工作电源电压:1.65 V to 5.5 V 工作温度范围:- 40 C to + 85 C 安装风格:SMD/SMT 封装 / 箱体:HVQFN-16 封装:Reel |
| PCA9674TS-T | 功能描述:接口-I/O扩展器 8-BIT I2C FM+ QB GPIO RST PU RoHS:否 制造商:NXP Semiconductors 逻辑系列: 输入/输出端数量: 最大工作频率:100 kHz 工作电源电压:1.65 V to 5.5 V 工作温度范围:- 40 C to + 85 C 安装风格:SMD/SMT 封装 / 箱体:HVQFN-16 封装:Reel |
发布紧急采购，3分钟左右您将得到回复。