PCA9535D,118

I/o Expanders Overview

The PCA9535D,118 is a 24-pin CMOS I/O expander providing 16 bits of General Purpose parallel Input/Output expansion for I2C-bus and SMBus applications. It operates within a supply voltage range of 2.3 V to 5.5 V and supports clock frequencies up to 400 kHz. The device features an active LOW interrupt output, polarity inversion registers, and noise filters on SCL/SDA inputs. It includes ESD protection exceeding 2000 V HBM and latch-up testing per JEDEC JESD78 standards. The component is housed in an SO24 package with an operating temperature range from -40 °C to +85 °C.

I/o Expanders Feature Summary

• Provides 16-bit GPIO expansion via I2C/SMBus interface
• Features active LOW interrupt output for input state changes
• Includes polarity inversion registers for flexible logic operation
• Offers 5 V tolerant I/Os with low standby current

I/o Expanders Applications

• ACPI power switches
• Sensor interfaces
• Push button detection
• LED control circuits
• Fan speed monitoring

I/o Expanders Procurement Notes

Verify the specific ordering suffix '118' corresponds to the REEL 13" Q1/T1 packing method as defined in the NXP datasheet. Confirm that the SO24 package variant matches the required PCB footprint dimensions. Ensure the procurement documentation explicitly references the PCA9535D part number to distinguish it from the PCA9535CD or other package options within the same family.

I/o Expanders Selection Notes

Select this component when 16-bit I/O expansion is required over standard I2C buses. It is suitable for designs needing individual I/O configuration and polarity inversion. Consider the PCA9535C variant if open-drain outputs are strictly required instead of the totum-pole outputs found in the standard PCA9535. Verify that the 2.3 V to 5.5 V supply range aligns with the system's power architecture.

I/o Expanders Part Context

The PCA9535 series enhances the NXP Semiconductors family of I2C-bus I/O expanders by offering higher drive capability and smaller packaging compared to predecessors. It is pin-to-pin and address compatible with the PCF8575, though software adjustments may be necessary due to architectural enhancements. The device shares the same fixed I2C-bus address structure as the PCA9555, allowing multiple devices to share the same bus.

I/o Expanders Replacement Considerations

PCA9535D,112 is a direct replacement using the same SO24 package but differs in packing method (Tube vs Reel). For TSSOP24 packages, consider PCA9535PW,118. If open-drain outputs are required, the PCA9535C series serves as the functional equivalent with modified output stages.