PCA9553D/01,112

Overview

The PCA9553D/01,112 is a 4-bit I²C-bus LED driver manufactured by NXP USA Inc. It features an internal oscillator providing two programmable blink rates to reduce bus traffic. The device supports open-drain outputs with a maximum sink current of 25 mA per bit and 100 mA per package. It operates within a supply voltage range of 2.3 V to 5.5 V and supports clock frequencies up to 400 kHz. The component is housed in an 8-TSSOP package and includes noise filters on SCL/SDA inputs.

Feature Summary

• Internal oscillator enables programmable blinking without external components
• Open-drain outputs directly drive LEDs with controlled edge rates
• Unused bits function as general-purpose parallel input/output

Applications

• I²C-bus and SMBus applications requiring limited bus traffic
• Systems needing to free up MCU timers for other tasks
• LED indicator control in embedded devices

Procurement Notes

Verify the specific suffix against manufacturer documentation, as variations like /01 and /112 may denote different fixed I²C addresses or packaging orientations. Confirm availability status, as some variants are marked End of Life or No Longer Manufactured. Ensure the selected part matches the required address configuration for the target bus topology.

Selection Notes

Select this component when hardware address pins are unavailable due to pin count limitations. Choose between /01 and /02 variants if multiple units must share the same I²C bus, as they possess distinct fixed addresses. Consider the 25 mA sink capability for direct LED driving without additional transistors.

Part Context

This part belongs to the PCA9553 family of LED blinkers designed to offload timing responsibilities from the main processor. Unlike standard I/O expanders, it integrates blinking functionality internally. The D package indicates a TSSOP form factor suitable for surface mount assembly.

Replacement Considerations

PCA9553DP/01,118

FAQ

How does the PCA9553 reduce I²C bus traffic?

It utilizes an internal oscillator to handle blinking automatically after initial programming, eliminating the need for repeated commands from the bus master.

Can unused outputs be used for other purposes?

Yes, any bits not configured for LED driving can be utilized as general-purpose parallel input/output (GPIO) expansion.