PCA9544APW,118

Specialized Overview

The PCA9544APW,118 is a 1-of-4 bidirectional translating multiplexer controlled via the I2C-bus. It fans out one upstream SCL/SDA pair to four downstream SCx/SDx pairs. The device operates within a supply voltage range of 2.3 V to 5.5 V and supports clock frequencies from 0 Hz to 400 kHz. It features low on-state resistance (Ron) switches with a maximum value of 24 Ohms at 5.5 V. The component includes four active LOW interrupt inputs and one active LOW interrupt output. It utilizes a TSSOP20 package.

Specialized Feature Summary

• Bidirectional voltage level translation between 1.8 V, 2.5 V, 3.3 V, and 5 V buses
• Active LOW interrupt logic for detecting devices on downstream channels
• Power-on reset function initializes registers and deselects all channels
• Supports hot insertion without generating glitches

Specialized Applications

• Expanding I2C/SMBus networks by connecting multiple downstream buses
• Voltage translation between different bus voltage levels
• Interrupt handling in multi-device I2C systems

Specialized Procurement Notes

Verify the specific ordering suffix '118' corresponds to the Reel 13” Q1/T1 packing method as documented in the NXP data sheet. Confirm that the TSSOP20 package variant matches the required board layout dimensions. Ensure compatibility with the specified operating temperature range of -40 °C to +85 °C for the target application environment.

Specialized Selection Notes

Select this component when a single I2C master needs to communicate with multiple downstream I2C slaves operating at different voltage levels. The PCA9544A provides interrupt capabilities to identify which channel generated an event. Consider the TSSOP20 package constraints regarding body width and lead pitch during PCB footprint design.

Specialized Part Context

The PCA9544A belongs to the PCA954X family of I2C/SMBus multiplexers and switches. This series allows system designers to expand I2C bus capacity and manage voltage domain crossings. The APW suffix specifically denotes the TSSOP20 plastic thin shrink small outline package version manufactured by NXP Semiconductors.

Specialized Replacement Considerations

Public confirmed substitute part numbers include PCA9544AD,118 (SO20 package) and PCA9544ABS,118 (HVQFN20 package). These variants share identical electrical characteristics and functionality but differ in physical package dimensions and pin configurations.