PCF8574 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 PCF8574 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 PCF8574 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 PCF8574 can remain a simple slave device
| PCF8574 | |
| 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, 16QFN, 16SOIC, 20TSSOP, 20TVSOP, 20VQFN |
| Operating Temperature Range(°C) | -40 to 85 |
| Max Frequency(kHz) | 100 |
| I2C Address | 0100 xxx |
| # of I/Os | 8 |
| Vcc range(V) | 2.5 to 6.0 |
| Push–Pull I/O Type | Yes |
PCF8574 特性
- Low Standby-Current Consumption of1 uA Max
- I2C to Parallel Port Expander
- Open-Drain Active-Low Interrupt Output
- 5-V Tolerant I/O Ports
- Compatible With Most Microcontrollers
- 400-kHz Fast I2C Bus
- Address by Three Hardware Address Pins for Use of up to Eight Devices
- Polarity Inversion Register
- Latched Outputs With High-Current Drive Capability for Directly Driving LEDs
- Latch-Up Performance Exceeds 100 mA Per JESD 78, Class II
- ESD Protection Exceeds JESD 22
- 2000-V Human-Body Model (A114-A)
- 200-V Machine Model (A115-A)
- 1000-V Charged-Device Model (C101)
PCF8574 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 |
| PCF8574DGVR | ACTIVE | -40 to 85 | 1.00 | 1ku | TVSOP (DGV) | 20 | 2000 | LARGE T&R | |
| PCF8574DGVRE4 | ACTIVE | -40 to 85 | 1.00 | 1ku | TVSOP (DGV) | 20 | 2000 | LARGE T&R | |
| PCF8574DGVRG4 | ACTIVE | -40 to 85 | 1.00 | 1ku | TVSOP (DGV) | 20 | 2000 | LARGE T&R | |
| PCF8574DW | ACTIVE | -40 to 85 | 1.15 | 1ku | SOIC (DW) | 16 | 40 | TUBE | |
| PCF8574DWE4 | ACTIVE | -40 to 85 | 1.15 | 1ku | SOIC (DW) | 16 | 40 | TUBE | |
| PCF8574DWG4 | ACTIVE | -40 to 85 | 1.15 | 1ku | SOIC (DW) | 16 | 40 | TUBE | |
| PCF8574DWR | ACTIVE | -40 to 85 | 1.00 | 1ku | SOIC (DW) | 16 | 2000 | LARGE T&R | |
| PCF8574DWRE4 | ACTIVE | -40 to 85 | 1.00 | 1ku | SOIC (DW) | 16 | 2000 | LARGE T&R | |
| PCF8574DWRG4 | ACTIVE | -40 to 85 | 1.00 | 1ku | SOIC (DW) | 16 | 2000 | LARGE T&R | |
| PCF8574N | ACTIVE | -40 to 85 | 1.00 | 1ku | PDIP (N) | 16 | 25 | TUBE | |
| PCF8574NE4 | ACTIVE | -40 to 85 | 1.00 | 1ku | PDIP (N) | 16 | 25 | TUBE | |
| PCF8574PW | ACTIVE | -40 to 85 | 1.15 | 1ku | TSSOP (PW) | 20 | 70 | TUBE | |
| PCF8574PWE4 | ACTIVE | -40 to 85 | 1.15 | 1ku | TSSOP (PW) | 20 | 70 | TUBE | |
| PCF8574PWG4 | ACTIVE | -40 to 85 | 1.15 | 1ku | TSSOP (PW) | 20 | 70 | TUBE | |
| PCF8574PWR | ACTIVE | -40 to 85 | 1.00 | 1ku | TSSOP (PW) | 20 | 2000 | LARGE T&R | |
| PCF8574PWRE4 | ACTIVE | -40 to 85 | 1.00 | 1ku | TSSOP (PW) | 20 | 2000 | LARGE T&R | |
| PCF8574PWRG4 | ACTIVE | -40 to 85 | 1.00 | 1ku | TSSOP (PW) | 20 | 2000 | LARGE T&R | |
| PCF8574RGTR | ACTIVE | -40 to 85 | 1.00 | 1ku | QFN (RGT) | 16 | 3000 | LARGE T&R | |
| PCF8574RGTRG4 | ACTIVE | -40 to 85 | 1.00 | 1ku | QFN (RGT) | 16 | 3000 | LARGE T&R | |
| PCF8574RGYR | ACTIVE | -40 to 85 | 1.00 | 1ku | VQFN (RGY) | 20 | 3000 | LARGE T&R | |
| PCF8574RGYRG4 | ACTIVE | -40 to 85 | 1.00 | 1ku | VQFN (RGY) | 20 | 3000 | LARGE T&R |
PCF8574 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 |
| PCF8574DGVR | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-1-260C-UNLIM | PCF8574DGVR | PCF8574DGVR |
| PCF8574DGVRE4 | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-1-260C-UNLIM | PCF8574DGVRE4 | PCF8574DGVRE4 |
| PCF8574DGVRG4 | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-1-260C-UNLIM | PCF8574DGVRG4 | PCF8574DGVRG4 |
| PCF8574DW | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-1-260C-UNLIM | PCF8574DW | PCF8574DW |
| PCF8574DWE4 | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-1-260C-UNLIM | PCF8574DWE4 | PCF8574DWE4 |
| PCF8574DWG4 | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-1-260C-UNLIM | PCF8574DWG4 | PCF8574DWG4 |
| PCF8574DWR | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-1-260C-UNLIM | PCF8574DWR | PCF8574DWR |
| PCF8574DWRE4 | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-1-260C-UNLIM | PCF8574DWRE4 | PCF8574DWRE4 |
| PCF8574DWRG4 | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-1-260C-UNLIM | PCF8574DWRG4 | PCF8574DWRG4 |
| PCF8574N | Pb-Free (RoHS) | CU NIPDAU | N/A for Pkg Type | PCF8574N | PCF8574N |
| PCF8574NE4 | Pb-Free (RoHS) | CU NIPDAU | N/A for Pkg Type | PCF8574NE4 | PCF8574NE4 |
| PCF8574PW | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-1-260C-UNLIM | PCF8574PW | PCF8574PW |
| PCF8574PWE4 | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-1-260C-UNLIM | PCF8574PWE4 | PCF8574PWE4 |
| PCF8574PWG4 | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-1-260C-UNLIM | PCF8574PWG4 | PCF8574PWG4 |
| PCF8574PWR | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-1-260C-UNLIM | PCF8574PWR | PCF8574PWR |
| PCF8574PWRE4 | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-1-260C-UNLIM | PCF8574PWRE4 | PCF8574PWRE4 |
| PCF8574PWRG4 | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-1-260C-UNLIM | PCF8574PWRG4 | PCF8574PWRG4 |
| PCF8574RGTR | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-1-260C-UNLIM | PCF8574RGTR | PCF8574RGTR |
| PCF8574RGTRG4 | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-1-260C-UNLIM | PCF8574RGTRG4 | PCF8574RGTRG4 |
| PCF8574RGYR | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-2-260C-1 YEAR | PCF8574RGYR | PCF8574RGYR |
| PCF8574RGYRG4 | Green (RoHS & no Sb/Br) | CU NIPDAU | Level-2-260C-1 YEAR | PCF8574RGYRG4 | PCF8574RGYRG4 |
PCF8574 应用技术支持与电子电路设计开发资源下载
- PCF8574 数据资料 dataSheet 下载.PDF
- TI 德州仪器I2C 逻辑器件产品选型与价格 . xls
- Logic Guide 2009 (PDF 4263 KB)
- Shelf-Life Evaluation of Lead-Free Component Finishes (PDF 1305 KB)
- Understanding and Interpreting Standard-Logic Data Sheets (PDF 857 KB)
- TI IBIS File Creation, Validation, and Distribution Processes (PDF 380 KB)
- Implications of Slow or Floating CMOS Inputs (PDF 101 KB)
- CMOS Power Consumption and CPD Calculation (PDF 89 KB)
- Designing With Logic (PDF 186 KB)
- Live Insertion (PDF 150 KB)
- Input and Output Characteristics of Digital Integrated Circuits (PDF 1708 KB)
- Using High Speed CMOS and Advanced CMOS in Systems With Multiple Vcc (PDF 43 KB)
- HiRel Unitrode Power Management Brochure (PDF 206 KB)
- LOGIC Pocket Data Book (PDF 6001 KB)
- HiRel Unitrode Power Management Brochure (PDF 206 KB)
- Logic Cross-Reference (PDF 2938 KB)