PCA9537DPZ

I/o Expanders Overview

The PCA9537DPZ is a 10-pin CMOS device providing 4-bit General Purpose parallel Input/Output (GPIO) expansion with interrupt and reset for I2C-bus/SMBus applications. It operates within a power supply voltage range of 2.3 V to 5.5 V and supports clock frequencies from 0 Hz to 400 kHz. The device features an open-drain active LOW interrupt output and an active LOW reset input. All four I/O pins default to inputs upon reset. It includes registers for configuration, input port data, output port data, and polarity inversion. The component is housed in a TSSOP10 package.

I/o Expanders Feature Summary

• Provides 4-bit GPIO expansion with configurable input/output directions via a Configuration register.
• Features an open-drain interrupt output that activates when any configured input state changes.
• Includes an active LOW reset input to initialize the device state machine without de-powering.
• Supports fixed I2C-bus addressing allowing only one device per bus line.

I/o Expanders Applications

• ACPI power switches
• Sensor interface expansion
• Push-button input monitoring
• LED control circuits

I/o Expanders Procurement Notes

Verify the specific ordering suffix 'Z' corresponds to the Static Shielding Bag packing method as documented in PCN 2020104008A. Confirm the device meets the required ambient temperature operating range of -40 °C to +85 °C. Ensure the procurement matches the TSSOP10 plastic thin shrink small outline package specification.

I/o Expanders Selection Notes

Select this component when a single I2C address is sufficient for the system design, as the address is fixed. Verify that the application requires exactly four expandable I/O lines. Ensure the host controller can manage the open-drain interrupt signaling. Check that the supply voltage falls within the 2.3 V to 5.5 V operational window.

I/o Expanders Part Context

The PCA9537DPZ is part of the NXP Semiconductors PCA9537 series of low-power I/O ports. It serves as a drop-in replacement for the previously discontinued PCA9537DP,118 variant, as indicated by Product Change Notice 2020104008A. This transition maintains functional compatibility while updating the packaging and ordering details.

I/o Expanders Replacement Considerations

The PCA9537DPZ is the designated drop-in replacement for the PCA9537DP,118 according to PCN 2020104008A. Both variants share identical electrical characteristics and pin configurations. No hardware modifications are required when transitioning between these specific part numbers.

I/o Expanders FAQ

How many devices can share the same I2C bus?

Only one PCA9537 device can be placed on the same I2C-bus or SMBus because its address is fixed.

What happens to the I/O pins at power-on reset?

At power-on reset, all four I/O pins are configured as inputs by default.

How is the interrupt signal cleared?

The interrupt is deactivated when the input returns to its previous state or when the Input Port register is read.