CY8C9520A-24PVXI

Overview

The CY8C9520A-24PVXI is a 20-bit I/O expander with integrated EEPROM, operating on a 3 V to 5.25 V supply within a -40°C to +85°C temperature range. It features an I2C interface compatible with SMBus and supports up to 100 kHz clock frequency. The device provides 20 independently configurable I/O pins and four 8-bit PWM outputs. It includes internal power-on reset, a watchdog timer, and interrupt capabilities for input changes and PWM state updates.

Feature Summary

• I/O pins are independently configurable as inputs, outputs, quasi-bidirectional, or PWM outputs with selectable drive modes including open drain and strong drive.
• Internal EEPROM allows storage of user default settings which are automatically restored upon power-up.
• Extendable soft addressing algorithm enables flexible I2C address configuration using available GPIO pins.

Applications

• Monitoring and controlling board-level devices such as LEDs.
• System intrusion detection applications.
• Storing error codes or manufacturing data in onboard EEPROM for diagnostic read-back.

Procurement Notes

Verify the component status as some sources indicate it may be discontinued. Confirm package type is SSOP-28 and ensure compatibility with I2C masters that support clock stretching. Check RoHS compliance and moisture sensitivity levels before integration.

Selection Notes

Select this model when 20 general-purpose I/O lines and four PWM channels are required. Ensure the system master supports I2C clock stretching. Consider the CY8C9540A or CY8C9560A if higher pin counts or more PWMs are needed.

Part Context

Part of the CY8C95xxA family of multi-port I/O expanders. Other members include CY8C9540A (40 bits) and CY8C9560A (60 bits). All devices share identical architecture but differ in I/O count, PWM sources, and EEPROM size.

Replacement Considerations

CY8C9540A offers 40 I/O pins and 8 PWMs. CY8C9560A provides 60 I/O pins and 16 PWMs. Both maintain the same I2C interface and EEPROM functionality.

FAQ

How does the Extendable Soft Addressing work?

It uses the A0 pin and optionally A1-A6 pins to define the I2C address. Pins not used for addressing can function as GPIOs.

What triggers the INT output signal?

The INT pin activates when an input pin level changes or a PWM state changes, provided the corresponding bit in the Interrupt Mask register is set low.

Can the EEPROM be write-disabled?

Yes, by setting the WD pin high or configuring specific registers to block write operations.