Overview
The PCA9539PW, although often associated with Burr Brown, is actually a product of NXP Semiconductors (now part of Nexperia). This component is a 24-pin CMOS device designed to provide 16 bits of General Purpose Input/Output (GPIO) expansion. It is particularly useful in applications requiring additional I/Os while minimizing interconnections, such as in ACPI power switches, sensors, push buttons, LEDs, and fan control.
Key Specifications
| Specification | Value |
|---|---|
| Package Type | TSSOP24 (SOT355-1) |
| Number of GPIOs | 16 bits |
| Supply Voltage Range | 2.3 V to 5.5 V |
| Clock Frequency | 400 kHz (Fast-mode I²C-bus) |
| Interrupt Output | Open-drain active LOW |
| Reset Input | Active LOW, requires pull-up to VCC |
| Operating Temperature Range | -40 °C to +85 °C |
| Standby Current Consumption | 1 µA (maximum) |
| ESD Protection | HBM: ANSI/ESDA/JEDEC JS-001 class 2 exceeds 2000 V, CDM: ANSI/ESDA/JEDEC JS-002 class C3 exceeds 1000 V |
| I/O Configuration | Each IO can be configured as input or output; default to inputs at power-up |
| Address Pins | A0 and A1 for configuring I²C bus slave address |
Key Features
GPIO Expansion: Provides 16 bits of General Purpose Input/Output expansion.
Interrupt and Reset: Features an open-drain active LOW interrupt output and a reset input for resetting the device to default values.
Wide Voltage Range: Operates over a voltage range of 2.3 V to 5.5 V.
Low Power Consumption: Ultra-low standby current consumption of 1 µA (maximum).
I²C-Bus Compatibility: Supports Fast-mode I²C-bus with a clock frequency of 400 kHz.
Noise Immunity: Schmitt-trigger action and noise filter on SCL and SDA inputs for better switching noise immunity.
ESD Protection: High ESD protection levels (HBM and CDM).
Latch-Up Performance: Exceeds 100 mA per JESD78, Class II.
Applications
ACPI Power Switches: Used in power management systems.
Sensors and Push Buttons: Ideal for interfacing with various sensors and push buttons.
LED and Fan Control: Can directly drive LEDs and control fans.
Automotive and Industrial: Finds applications in automotive, industrial, and other sectors where additional I/Os are required.
Q & A
- What is the PCA9539PW used for?
The PCA9539PW is used for providing 16 bits of General Purpose Input/Output (GPIO) expansion with interrupt and reset capabilities for I²C-bus/SMBus applications.
- What is the operating voltage range of the PCA9539PW?
The PCA9539PW operates over a voltage range of 2.3 V to 5.5 V.
- What is the clock frequency of the I²C-bus in the PCA9539PW?
The clock frequency of the I²C-bus in the PCA9539PW is 400 kHz.
- Does the PCA9539PW have ESD protection?
Yes, the PCA9539PW has high ESD protection levels, exceeding 2000 V for HBM and 1000 V for CDM.
- How many devices can share the same I²C-bus/SMBus using the PCA9539PW?
Up to four devices can share the same I²C-bus/SMBus using the address pins A0 and A1.
- What is the default state of the I/O pins at power-up?
All I/O pins default to inputs at power-up.
- Can the polarity of the read register be inverted?
Yes, the polarity inversion register can be programmed to invert the polarity of the read register.
- What is the purpose of the RESET pin?
The RESET pin is used to reset the device to its default values without power cycling; it requires a pull-up to VCC.
- What is the maximum drive capability of the latched outputs?
The latched outputs have a maximum drive capability of 25 mA.
- What is the standby current consumption of the PCA9539PW?
The standby current consumption is 1 µA (maximum).
