PCA8575DK,118

I/o Expanders Overview

The PCA8575DK,118 is a remote 16-bit I/O expander for the I2C-bus with interrupt output. It provides general-purpose I/O expansion via a two-line bidirectional I2C interface (SCL, SDA). The device features a 16-bit quasi-bidirectional port and latched outputs with high current drive capability for directly driving LEDs. It includes an active LOW open-drain interrupt line that allows the remote I/O to inform the microcontroller of incoming data without bus communication. The internal Power-On Reset initializes the I/Os as inputs. Operating voltage ranges from 2.3 V to 5.5 V with 5.5 V tolerant I/Os. It supports up to 400 kHz I2C clock frequency and offers 8 programmable slave addresses using three address pins.

I/o Expanders Feature Summary

• Provides 16-bit remote I/O expansion via standard I2C-bus interface
• Features latched outputs with high current sink capability for direct LED driving
• Includes active LOW open-drain interrupt output for efficient host notification
• Supports multiple slave addressing through hardware-configurable address pins

I/o Expanders Applications

• LED signs and displays
• Industrial control systems
• Medical equipment
• Programmable logic controllers (PLCs)
• Cellular telephones

I/o Expanders Procurement Notes

Verify the specific ordering suffix DK,118 corresponds to the SSOP24 package variant with a body width of 3.9 mm and lead pitch of 0.635 mm. Confirm the datasheet revision matches the required specifications for your design. Ensure compatibility with the target microcontroller's I2C voltage levels and interrupt handling logic before finalizing procurement.

I/o Expanders Selection Notes

Select this component when expanding I/O capacity for microcontrollers over an I2C bus is required. It is suitable for applications needing direct LED driving or interrupt-driven input monitoring. Consider the SSOP24 package constraints regarding board space and thermal performance. Verify that the 25 mA per pin and 400 mA total package sink limits meet the load requirements of the connected peripherals.

I/o Expanders Part Context

The PCA8575 series serves as a drop-in replacement for the PCF8575 in many designs, offering similar functionality with minor differences in interrupt release timing during read operations. The DK variant specifically denotes the SSOP24 package form factor. This family is widely used in embedded systems requiring additional GPIO pins without consuming microcontroller resources.

I/o Expanders Replacement Considerations

The PCA9673 is a functional upgrade offering higher I2C speed (1 MHz) and increased drive capabilities. For direct pin-to-pin substitution with identical electrical characteristics, the PCF8575 is compatible, though interrupt clearing behavior differs during read cycles.