参数资料
| 型号： | PCA8574D,518 |
| 厂商： | NXP Semiconductors |
| 文件页数： | 5/32页 |
| 文件大小： | 0K |
| 描述： | IC I/O EXPANDER I2C 8B 16SOIC |
| 标准包装： | 1,000 |
| 接口： | I²C |
| 输入/输出数： | 8 |
| 中断输出： | 是 |
| 频率 - 时钟： | 400kHz |
| 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-SOIC（0.295"，7.50mm 宽） |
| 供应商设备封装： | 16-SO |
| 包装： | 带卷 (TR) |
| 包括： | POR |
| 其它名称： | 935283485518 PCA8574D-T PCA8574D-T-ND |
第1页第2页第3页第4页当前第5页第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
PCA8574_PCA8574A
All information provided in this document is subject to legal disclaimers.
NXP B.V. 2013. All rights reserved.
Product data sheet
Rev. 3 — 3 June 2013
13 of 32
NXP Semiconductors
PCA8574; PCA8574A
Remote 8-bit I/O expander for I2C-bus with interrupt
10. Application design-in information
10.1 Bidirectional I/O expander applications
In the 8-bit I/O expander application shown in Figure 15, P0 and P1 are inputs, and
P2 to P7 are outputs. When used in this configuration, during a write, the input (P0 and
P1) must be written as HIGH so the external devices fully control the input ports.
The desired HIGH or LOW logic levels may be written to the ports used as outputs (P2 to
P7). If 10
A internal output HIGH is not enough current source, the port needs external
pull-up resistor. During a read, the logic levels of the external devices driving the input
ports (P0 and P1) and the previous written logic level to the output ports (P2 to P7) will be
read.
The GPIO also has an interrupt line (INT) that can be connected to the interrupt logic of
the microcontroller. By sending an interrupt signal on this line, the remote I/O informs the
microprocessor that there has been a change of data on its ports without having to
communicate via the I2C-bus.
10.2 How to read and write to I/O expander (example)
In the application example of PCA8574 shown in Figure 15, the microcontroller wants to
control the P3 switch ON and the P7 LED ON when the temperature sensor P0 changes.
1. When the system power on:
Core Processor needs to issue an initial command to set P0 and P1 as inputs and
P[7:2] as outputs with value 1010 00 (LED off, MP3 off, camera on, audio off,
switch off and latch off).
2. Operation:
When the temperature changes above the threshold, the temperature sensor signal
will toggle from HIGH to LOW. The INT will be activated and notifies the ‘core
processor’ that there have been changes on the input pins. Read the input register.
If P0 = 0 (temperature sensor has changed), then turn on LED and turn on switch.
3. Software code:
//System Power on
// write to PCA8574 with data 1010 0011b to set P[7:2] outputs and P[1:0] inputs
<S> <0100 0000> <ACK> <1010 0011> <ACK> <P>//Initial setting for PCA8574
Fig 15. Bidirectional I/O expander application
002aah625
VDD
temperature sensor
battery status
control for latch
control for switch
control for audio
control for camera
control for MP3
P0
P1
P2
P3
P4
P5
P6
P7
VDD
SDA
SCL
INT
A0
A1
A2
CORE
PROCESSOR
VDD
相关PDF资料 |
PDF描述 |
|---|---|
| PCA8574AD,518 | IC I/O EXPANDER I2C 8B 16SOIC |
| PCA8574TS,112 | IC I/O EXPANDER I2C 8B 20SSOP |
| ATTINY861-15XZ | MCU AVR 8K FLASH 15MHZ 20-TSSOP |
| ATTINY861-15MZ | MCU AVR 8K FLASH 15MHZ 32-QFN |
| PCA8574ATS,112 | IC I/O EXPANDER I2C 8B 20SSOP |
相关代理商/技术参数 |
参数描述 |
|---|---|
| PCA8574D-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 |
| PCA8574N | 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 |
| PCA8574N,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 |
| PCA8574PW | 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 |
| PCA8574PW,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 |
发布紧急采购，3分钟左右您将得到回复。