PCA9553TK,118

Overview

The PCA9553TK,118 is a 4-bit I2C-bus and SMBus LED blinker IC manufactured by NXP Semiconductors. It features an internal oscillator with two fully programmable blink rates, reducing bus traffic compared to standard GPIO expanders. The device provides open-drain outputs capable of sinking up to 25 mA per bit and 100 mA total 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. Packaged in an HVSON-8 surface-mount format, it includes power-on reset functionality and ESD protection exceeding 2 kV HBM.

Feature Summary

• Internal oscillator enables programmable blinking without external components or continuous bus commands
• Dual selectable blink rates allow independent frequency and duty cycle programming for each output
• Unused bits function as general-purpose parallel input/output (GPIO) for expanded system control

Applications

• I2C-bus applications requiring limited bus traffic
• Microcontroller timer resource conservation
• LED status indication systems
• SMBus compatible embedded designs

Procurement Notes

Verify the specific ordering suffix ,118 corresponds to the HVSON-8 package variant when sourcing. Confirm that the fixed I2C address matches your system topology, as this model lacks hardware address pins. Ensure compatibility with the 2.3 V to 5.5 V operating range and check for any end-of-life notices from the manufacturer before finalizing procurement plans.

Selection Notes

Select this component when minimizing I2C bus overhead is critical, as it offloads blinking tasks from the main controller. Choose over standard GPIO expanders if hardware timers are scarce. Verify that the 25 mA per-bit sink current meets LED requirements. Consider the fixed address limitation if multiple identical devices must operate on the same bus simultaneously.

Part Context

This part belongs to the PCA9553 series of LED blinkers designed to reduce microcontroller load. Unlike generic I/O expanders, it integrates timing functions internally. The TK suffix indicates the HVSON-8 package type. It complements other NXP interface solutions like the PCA9536 and PCA9539 by offering specialized lighting control capabilities within the same I2C ecosystem.

Replacement Considerations

Public confirmed substitute part numbers: PCA9553DP/01,118, PCA9553D,118.