Overview
The PCF8574TS/3,112 from NXP USA Inc. is a remote 8-bit I/O expander designed for use with the I²C-bus interface. This device provides general-purpose remote I/O expansion, making it suitable for a variety of applications requiring additional I/O ports. The PCF8574TS operates within a supply voltage range of 2.5 V to 6 V and features a 100 kHz I²C-bus interface, allowing for efficient communication with the system master.
Key Specifications
| Parameter | Value |
|---|---|
| Supply Voltage Range | 2.5 V to 6 V |
| I²C-bus Interface Frequency | 100 kHz (Standard-mode I²C-bus) |
| Number of I/O Ports | 8 quasi-bidirectional ports |
| Package Type | SSOP-20 |
| Operating Temperature Range | -40°C to +85°C |
| Interrupt Output | Active LOW open-drain interrupt output |
| Addressing Capability | Eight programmable slave addresses using three address pins |
| Standby Current | 2.5 µA (typical) |
| ESD Protection | Exceeds 2000 V HBM per JESD22-A114 and 1000 V CDM per JESD22-C101 |
Key Features
- I²C-bus to parallel port expander
- 8-bit remote I/O pins that default to inputs at power-up
- Latched outputs directly drive LEDs
- Total package sink capability of 80 mA
- Active LOW open-drain interrupt output
- Eight programmable slave addresses using three address pins
- Low standby current (2.5 µA typical)
- Internal Power-On Reset (POR) initializes the I/Os as inputs with a weak internal pull-up 100 µA current source
Applications
The PCF8574TS is versatile and can be used in various applications, including:
- Mobile devices due to its low current consumption
- Industrial control systems requiring additional I/O ports
- Automotive systems for expanding I/O capabilities
- Consumer electronics for controlling LEDs and other indicator devices
- Embedded systems where I²C-bus communication is utilized
Q & A
- What is the primary function of the PCF8574TS?
The primary function of the PCF8574TS is to provide general-purpose remote I/O expansion via the I²C-bus interface.
- What is the operating supply voltage range of the PCF8574TS?
The operating supply voltage range is 2.5 V to 6 V.
- How many I/O ports does the PCF8574TS have?
The device has 8 quasi-bidirectional I/O ports.
- What is the frequency of the I²C-bus interface?
The I²C-bus interface operates at 100 kHz (Standard-mode I²C-bus).
- What type of package does the PCF8574TS come in?
The device is packaged in a SSOP-20 package.
- What is the operating temperature range of the PCF8574TS?
The operating temperature range is -40°C to +85°C.
- Does the PCF8574TS have an interrupt output?
Yes, it has an active LOW open-drain interrupt output.
- How many devices can be connected on the same I²C-bus?
Up to 16 devices (8 of each PCF8574 and PCF8574A) can be connected on the same I²C-bus, supporting up to 128 I/Os.
- What is the standby current of the PCF8574TS?
The standby current is 2.5 µA (typical).
- Does the PCF8574TS have ESD protection?
Yes, it exceeds 2000 V HBM per JESD22-A114 and 1000 V CDM per JESD22-C101.
