Overview
The PCA9555AHF128, produced by NXP USA Inc., is a low-voltage 16-bit General Purpose Input/Output (GPIO) expander designed for I²C-bus/SMBus applications. This device provides a simple and efficient solution for expanding the I/O capabilities of microprocessors and microcontrollers, particularly in scenarios where additional I/Os are required without increasing the interconnections. The PCA9555AHF128 is part of NXP's extensive range of I/O expanders, known for their versatility and low power consumption.
Key Specifications
| Attribute | Value |
|---|---|
| Package | TSSOP-24, HWQFN24 |
| Operating Power Supply Voltage | 1.65 V to 5.5 V |
| Standby Current Consumption | 1.5 μA (typical at 5 V VDD), 1.0 μA (typical at 3.3 V VDD) |
| I²C-bus Frequency | 400 kHz Fast-mode |
| Interrupt Output | Open-drain active LOW interrupt output (INT) |
| I/O Configuration | 16 bits of GPIO, configurable as inputs or outputs with weak pull-up resistors |
| Output Drive Capability | Latched outputs with 25 mA drive maximum capability for directly driving LEDs |
| Input/Output Tolerance | 5 V tolerant I/Os |
Key Features
- Low-voltage operation with a wide VDD range of 1.65 V to 5.5 V, making it compatible with next-generation microprocessors and microcontrollers.
- Low standby current consumption to conserve power.
- Schmitt-trigger action on SCL and SDA inputs for better switching noise immunity.
- Internal power-on reset and power-up with all channels configured as inputs with weak pull-up resistors.
- No glitch on power-up.
- 400 kHz Fast-mode I²C-bus interface.
- Open-drain active LOW interrupt output (INT).
- Latched outputs with 25 mA drive maximum capability for directly driving LEDs.
Applications
- ACPI power switches.
- Sensors and push buttons.
- LED control and fan control.
- General-purpose I/O expansion in various embedded systems.
- Automotive and industrial control systems where additional I/Os are needed.
Q & A
- What is the PCA9555AHF128 used for?
The PCA9555AHF128 is used as a 16-bit General Purpose Input/Output (GPIO) expander for I²C-bus/SMBus applications, providing additional I/O capabilities to microprocessors and microcontrollers.
- What is the operating voltage range of the PCA9555AHF128?
The operating voltage range is from 1.65 V to 5.5 V.
- What is the typical standby current consumption of the PCA9555AHF128?
The typical standby current consumption is 1.5 μA at 5 V VDD and 1.0 μA at 3.3 V VDD.
- What is the I²C-bus frequency supported by the PCA9555AHF128?
The device supports 400 kHz Fast-mode I²C-bus.
- Does the PCA9555AHF128 have an interrupt output?
Yes, it has an open-drain active LOW interrupt output (INT).
- What is the output drive capability of the PCA9555AHF128?
The device has latched outputs with a 25 mA drive maximum capability, suitable for directly driving LEDs.
- Are the I/Os of the PCA9555AHF128 5 V tolerant?
Yes, the I/Os are 5 V tolerant.
- What kind of reset does the PCA9555AHF128 have?
The device has an internal power-on reset.
- How are the channels configured on power-up?
All channels are configured as inputs with weak pull-up resistors on power-up.
- Does the PCA9555AHF128 have any noise immunity features?
Yes, it has Schmitt-trigger action on SCL and SDA inputs for better switching noise immunity.
