NXP Semiconductors PCA9674TS,112

Overview

PCA9674TS,112 from NXP Semiconductors is an 8-bit quasi-bidirectional I²C-bus I/O expander with Fast-mode Plus (1 MHz) interface, active-low open-drain interrupt output (INT), and 25 mA per-pin sink capability for direct LED driving. It operates from 2.3 V to 5.5 V, features 64 programmable slave addresses via AD0–AD2, and supports up to 1008 I/Os on a single bus when combined with PCA9674A devices - ideal for LED signage and industrial control panels.

For engineers reviewing the PCA9674TS,112 datasheet, PCA9674TS,112 pinout, PCA9674TS,112 application, or PCA9674TS,112 equivalent, key selection criteria include its 1 MHz Fm+ I²C compatibility, 25 mA per-port sink drive, interrupt-driven input monitoring, 4.5 µA standby current, and TSSOP16 package suitability for space-constrained embedded designs.

Technical Context

The PCA9674TS,112 implements a quasi-bidirectional I/O architecture with no direction register: each of P0–P7 defaults to input at power-up with a 100 µA weak pull-up, and functions as either input or output based solely on the value written to the single port register. Input state changes trigger the INT pin, enabling efficient event-driven polling instead of continuous bus reads.

Its Fast-mode Plus I²C interface supports 1 MHz operation with 30 mA SDA sink capability, allowing up to 4000 pF bus capacitance without buffers. The device includes software reset (via General Call + 06h) and read-only Device ID (manufacturer, part ID, revision), both accessible over I²C without additional pins.

Key Specifications

Pinout & Package

Packaged in TSSOP16 (SOT403-1), the PCA9674TS,112 uses a 4.4 mm body-width surface-mount footprint compatible with automated assembly and thermal vias for enhanced reliability.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar I/O expansion applications.

Compared with PCA9674PW,112 and PCA9674D,512, the PCA9674TS,112 offers identical core functionality in a space-optimized TSSOP16 package with standardized SMD reel packaging - making it optimal for automated SMT production of compact embedded systems requiring high I/O density and low standby power.

Availability

PCA9674TS,112 is available at Aetrix Electronics and suitable for LED signage, industrial control panels, and medical UI systems requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for PCA9674TS,112 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

NXP Semiconductors is a global semiconductor leader focused on secure connectivity solutions for automotive, industrial, and IoT applications.

The PCA9674 series belongs to NXP's I²C peripheral portfolio, designed specifically for low-power, interrupt-driven remote I/O expansion in resource-constrained embedded systems with strict board-area and power budgets.

FAQ

What is the I²C bus speed supported by the PCA9674TS,112?

The PCA9674TS,112 supports Fast-mode Plus (Fm+) I²C operation up to 1 MHz. This enables high-speed communication with microcontrollers while maintaining compatibility with standard I²C protocols. Its SDA line provides 30 mA sink capability, allowing reliable operation on buses with up to 4000 pF capacitance - eliminating the need for bus buffers in most medium-complexity designs using the PCA9674TS,112.

How does the interrupt (INT) pin function on the PCA9674TS,112?

The INT pin on the PCA9674TS,112 is an active-low open-drain output that asserts whenever the state of any input port (P0–P7) differs from its corresponding bit in the input port register. This allows the host microcontroller to respond to input changes asynchronously rather than polling. The PCA9674TS,112 requires an external pull-up resistor on INT, and the signal remains asserted until the host reads the port register - ensuring no edge is missed in event-driven applications.

Can the PCA9674TS,112 drive LEDs directly without external components?

Yes, the PCA9674TS,112 can drive standard LEDs directly: each of its eight quasi-bidirectional ports (P0–P7) provides 25 mA sink current capability, sufficient for common indicator LEDs. When configured as an output, writing '0' activates the strong internal pull-down transistor. The device's total package sink limit is 200 mA, so simultaneous full-drive across all ports must be managed within that constraint - a key design consideration when implementing LED arrays with the PCA9674TS,112.

What is the purpose of the AD0, AD1, and AD2 pins on the PCA9674TS,112?

The AD0, AD1, and AD2 pins on the PCA9674TS,112 are hardware-configurable address inputs that determine the device's 7-bit I²C slave address. By connecting each to VDD, VSS, SCL, or SDA, they generate 64 unique addresses - enabling up to 64 PCA9674TS,112 units (or combined with PCA9674A variants) on a single I²C bus. These pins have no internal pull-ups, so external termination is mandatory for deterministic addressing - a critical layout requirement for reliable PCA9674TS,112 system integration.

Does the PCA9674TS,112 include a software reset feature?

Yes, the PCA9674TS,112 supports software reset via the I²C bus using the General Call address (00h) followed by the data byte 06h. Upon successful reception, the device resets all internal registers to their power-on default states - including setting all I/Os as inputs with 100 µA pull-ups. This eliminates the need for a dedicated hardware reset line and simplifies system recovery sequences, especially in distributed I²C networks where the PCA9674TS,112 may be deployed remotely from the host controller.