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PCF8574A 用于 I2C 总线的远程 8 位 I/O 扩展器

This 8-bit input/output (I/O) expander for the two-line bidirectional bus (I2C) is designed for 2.5-V to 6-V VCC operation.

The PCF8574A provides general-purpose remote I/O expansion for most microcontroller families via the I2C interface [serial clock (SCL), serial data (SDA)].

The device features an 8-bit quasi-bidirectional I/O port (P0-P7), including latched outputs with high-current drive capability for directly driving LEDs. Each quasi-bidirectional I/O can be used as an input or output without the use of a data-direction control signal. At power on, the I/Os are high. In this mode, only a current source to VCC is active. An additional strong pullup to VCC allows fast rising edges into heavily loaded outputs. This device turns on when an output is written high and is switched off by the negative edge of SCL. The I/Os should be high before being used as inputs.

The PCF8574A provides an open-drain output (INT) that can be connected to the interrupt input of a microcontroller. An interrupt is generated by any rising or falling edge of the port inputs in the input mode. After time, tiv, INT is valid. Resetting and reactivating the interrupt circuit is achieved when data on the port is changed to the original setting or data is read from, or written to, the port that generated the interrupt. Resetting occurs in the read mode at the acknowledge bit after the rising edge of the SCL signal, or in the write mode at the acknowledge bit after the high-to-low transition of the SCL signal. Interrupts that occur during the acknowledge clock pulse can be lost (or be very short) due to the resetting of the interrupt during this pulse. Each change of the I/Os after resetting is detected and, after the next rising clock edge, is transmitted as INT. Reading from, or writing to, another device does not affect the interrupt circuit.

By sending an interrupt signal on this line, the remote I/O can inform the microcontroller if there is incoming data on its ports without having to communicate via the I2C bus. Therefore, the PCF8574A can remain a simple slave device

PCF8574A
Voltage Nodes(V) 5, 3.3
Interrupt Output Yes
Reset Input No
fSCLK(Max)(MHz) 0.1
VCC(Min)(V) 2.5
VCC(Max)(V) 6
Pin/Package 16PDIP, 16SOIC, 20TSSOP, 20TVSOP, 20VQFN
Operating Temperature Range(°C) -40 to 85
Max Frequency(kHz) 100
I2C Address 0111 xxx
# of I/Os 8
Vcc range(V) 2.5 to 6.0
Push–Pull I/O Type Yes
PCF8574A 特性
PCF8574A 芯片订购指南
器件 状态 温度 价格 封装 | 引脚 封装数量 | 封装载体 丝印标记
PCF8574ADGVR ACTIVE -40 to 85 1.00 | 1ku TVSOP (DGV) | 20 2000 | LARGE T&R  
PCF8574ADGVRE4 ACTIVE -40 to 85 1.00 | 1ku TVSOP (DGV) | 20 2000 | LARGE T&R  
PCF8574ADGVRG4 ACTIVE -40 to 85 1.00 | 1ku TVSOP (DGV) | 20 2000 | LARGE T&R  
PCF8574ADW ACTIVE -40 to 85 1.15 | 1ku SOIC (DW) | 16 40 | TUBE  
PCF8574ADWE4 ACTIVE -40 to 85 1.15 | 1ku SOIC (DW) | 16 40 | TUBE  
PCF8574ADWG4 ACTIVE -40 to 85 1.15 | 1ku SOIC (DW) | 16 40 | TUBE  
PCF8574ADWR ACTIVE -40 to 85 1.00 | 1ku SOIC (DW) | 16 2000 | LARGE T&R  
PCF8574ADWRE4 ACTIVE -40 to 85 1.00 | 1ku SOIC (DW) | 16 2000 | LARGE T&R  
PCF8574ADWRG4 ACTIVE -40 to 85 1.00 | 1ku SOIC (DW) | 16 2000 | LARGE T&R  
PCF8574AN ACTIVE -40 to 85 1.00 | 1ku PDIP (N) | 16 25 | TUBE  
PCF8574ANE4 ACTIVE -40 to 85 1.00 | 1ku PDIP (N) | 16 25 | TUBE  
PCF8574APW ACTIVE -40 to 85 1.15 | 1ku TSSOP (PW) | 20 70 | TUBE  
PCF8574APWE4 ACTIVE -40 to 85 1.15 | 1ku TSSOP (PW) | 20 70 | TUBE  
PCF8574APWG4 ACTIVE -40 to 85 1.15 | 1ku TSSOP (PW) | 20 70 | TUBE  
PCF8574APWR ACTIVE -40 to 85 1.00 | 1ku TSSOP (PW) | 20 2000 | LARGE T&R  
PCF8574APWRE4 ACTIVE -40 to 85 1.00 | 1ku TSSOP (PW) | 20 2000 | LARGE T&R  
PCF8574APWRG4 ACTIVE -40 to 85 1.00 | 1ku TSSOP (PW) | 20 2000 | LARGE T&R  
PCF8574ARGTR ACTIVE -40 to 85 1.00 | 1ku QFN (RGT) | 16 3000 | LARGE T&R  
PCF8574ARGTRG4 ACTIVE -40 to 85 1.00 | 1ku QFN (RGT) | 16 3000 | LARGE T&R  
PCF8574ARGYR ACTIVE -40 to 85 1.00 | 1ku VQFN (RGY) | 20 3000 | LARGE T&R  
PCF8574ARGYRG4 ACTIVE -40 to 85 1.00 | 1ku VQFN (RGY) | 20 3000 | LARGE T&R  
PCF8574A 质量与无铅数据
器件 环保计划* 铅/焊球涂层 MSL 等级/回流焊峰 环保信息与无铅 (Pb-free) DPPM / MTBF / FIT 率
PCF8574ADGVR Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM PCF8574ADGVR PCF8574ADGVR
PCF8574ADGVRE4 Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM PCF8574ADGVRE4 PCF8574ADGVRE4
PCF8574ADGVRG4 Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM PCF8574ADGVRG4 PCF8574ADGVRG4
PCF8574ADW Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM PCF8574ADW PCF8574ADW
PCF8574ADWE4 Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM PCF8574ADWE4 PCF8574ADWE4
PCF8574ADWG4 Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM PCF8574ADWG4 PCF8574ADWG4
PCF8574ADWR Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM PCF8574ADWR PCF8574ADWR
PCF8574ADWRE4 Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM PCF8574ADWRE4 PCF8574ADWRE4
PCF8574ADWRG4 Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM PCF8574ADWRG4 PCF8574ADWRG4
PCF8574AN Pb-Free (RoHS) CU NIPDAU N/A for Pkg Type PCF8574AN PCF8574AN
PCF8574ANE4 Pb-Free (RoHS) CU NIPDAU N/A for Pkg Type PCF8574ANE4 PCF8574ANE4
PCF8574APW Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM PCF8574APW PCF8574APW
PCF8574APWE4 Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM PCF8574APWE4 PCF8574APWE4
PCF8574APWG4 Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM PCF8574APWG4 PCF8574APWG4
PCF8574APWR Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM PCF8574APWR PCF8574APWR
PCF8574APWRE4 Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM PCF8574APWRE4 PCF8574APWRE4
PCF8574APWRG4 Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM PCF8574APWRG4 PCF8574APWRG4
PCF8574ARGTR Green (RoHS & no Sb/Br) CU NIPDAU Level-1-260C-UNLIM PCF8574ARGTR PCF8574ARGTR
PCF8574ARGYR Green (RoHS & no Sb/Br) CU NIPDAU Level-2-260C-1 YEAR PCF8574ARGYR PCF8574ARGYR
PCF8574ARGYRG4 Green (RoHS & no Sb/Br) CU NIPDAU Level-2-260C-1 YEAR PCF8574ARGYRG4 PCF8574ARGYRG4
PCF8574A 应用技术支持与电子电路设计开发资源下载
  1. PCF8574A 数据资料 dataSheet 下载.PDF
  2. TI 德州仪器I2C 逻辑器件产品选型与价格 . xls
  3. Logic Guide 2009 (PDF 4263 KB)
  4. Shelf-Life Evaluation of Lead-Free Component Finishes (PDF 1305 KB)
  5. Understanding and Interpreting Standard-Logic Data Sheets (PDF 857 KB)
  6. TI IBIS File Creation, Validation, and Distribution Processes (PDF 380 KB)
  7. Implications of Slow or Floating CMOS Inputs (PDF 101 KB)
  8. CMOS Power Consumption and CPD Calculation (PDF 89 KB)
  9. Designing With Logic (PDF 186 KB)
  10. Live Insertion (PDF 150 KB)
  11. Input and Output Characteristics of Digital Integrated Circuits (PDF 1708 KB)
  12. Using High Speed CMOS and Advanced CMOS in Systems With Multiple Vcc (PDF 43 KB)
  13. HiRel Unitrode Power Management Brochure (PDF 206 KB)
  14. LOGIC Pocket Data Book (PDF 6001 KB)
  15. HiRel Unitrode Power Management Brochure (PDF 206 KB)
  16. Logic Cross-Reference (PDF 2938 KB)