PCA9539RPW/Q900J

I/o Expanders Overview

The PCA9539RPW/Q900J is a 24-pin CMOS device providing 16 bits of general-purpose parallel input/output expansion with interrupt and reset capabilities for I2C-bus/SMBus applications. It operates within a supply voltage range of 2.3 V to 5.5 V, featuring 5 V tolerant I/Os and an active LOW open-drain interrupt output. The device includes polarity inversion registers and noise filters on SCL/SDA inputs. It supports clock frequencies from 0 Hz to 400 kHz and offers ESD protection exceeding 2000 V HBM. Packaged in TSSOP24, it is AEC-Q100 qualified for automotive environments.

I/o Expanders Feature Summary

• Provides 16-bit GPIO expansion with configurable input/output directions via configuration registers.
• Features an active LOW open-drain interrupt output that activates when input states change.
• Includes a hardware RESET pin to initialize the state machine without affecting internal register data.
• Supports up to four devices on a single bus using two hardware address pins.

I/o Expanders Applications

• ACPI power switches
• Sensor interfaces
• Push button scanning
• LED control circuits

I/o Expanders Procurement Notes

Verify the specific suffix Q900J indicates AEC-Q100 qualification and extended temperature range. Confirm package type matches TSSOP24 requirements. Check RoHS compliance status against current regulatory standards. Ensure ordering information aligns with the manufacturer's latest datasheet revision.

I/o Expanders Selection Notes

Select this component when low standby current is critical compared to standard I/O expanders. Use the PCA9539 variant if full register reset on hardware signal is required instead of state machine reset only. Verify 5 V tolerance compatibility with system logic levels. Ensure I2C bus speed requirements do not exceed 400 kHz.

I/o Expanders Part Context

This part belongs to the PCA9539 family, developed to enhance NXP Semiconductors' I2C-bus I/O expander lineup. It is functionally identical to the PCA9555 but lacks internal I/O pull-up resistors to reduce power consumption. It replaces the A2 pin with a dedicated RESET input and utilizes a distinct address range.

I/o Expanders Replacement Considerations

PCA9555 serves as a functional alternative with internal pull-ups. PCA9539PW/Q900 shares similar specifications but may differ in temperature rating or packaging options. Verify electrical characteristics and pinout compatibility before substitution.