NXP Semiconductors PCA9674ATS,118

Overview

PCA9674ATS,118 from NXP Semiconductors is an 8-bit remote I/O expander for Fast-mode Plus (Fm+) I²C-bus with interrupt output, operating from 2.3 V to 5.5 V, supporting 1 MHz bus speed, 25 mA per port sink drive for direct LED control, and active-low open-drain INT pin for change-of-state notification. It is used in LED signage, industrial PLCs, and keypad interfaces where space-constrained I/O expansion is required.

For engineers reviewing the PCA9674ATS,118 datasheet, PCA9674ATS,118 pinout, PCA9674ATS,118 application, or PCA9674ATS,118 equivalent, this device delivers quasi-bidirectional I/O with hardware address selection (AD0–AD2), software reset capability, readable device ID, and 4.5 µA typical standby current - critical for low-power embedded systems and mobile I/O extension.

Technical Context

The PCA9674ATS,118 implements a quasi-bidirectional I/O architecture with no direction register: each of P0–P7 defaults to input at power-up with 100 µA weak pull-up, and writes of '1' or '0' dynamically configure high-impedance input or active sink output. Its Fm+ interface supports 1 MHz clocking and 30 mA SDA sink capability for driving up to 4000 pF bus loads without buffers.

Interrupt logic monitors input state changes against register values and asserts active-low INT; internal Power-On Reset initializes all ports as inputs. The device supports 64 unique slave addresses via AD0/AD1/AD2 (VDD/VSS/SCL/SDA combinations) and includes a dedicated Device ID read sequence (F8h address) returning manufacturer, part ID, and revision bits.

Key Specifications

Pinout & Package

PCA9674ATS,118 is packaged in TSSOP16 (SOT403-1), a 4.4 mm body-width, 16-pin thin shrink small outline package suitable for high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with PCA9674PW,118 and PCA9674D,518, the PCA9674ATS,118 offers identical core I/O expansion functionality in the space-optimized TSSOP16 package with "674" top-side marking - making it ideal for new designs prioritizing PCB area and modern SMT processes.

Availability

PCA9674ATS,118 is available at Aetrix Electronics and suitable for LED signage, industrial PLCs, and medical panel control requiring stable component supply across extended production lifecycles.

Supply support for PCA9674ATS,118 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 company headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and IoT applications.

The PCA9674 family is designed for reliable, low-power I/O expansion in resource-constrained embedded systems - delivering interrupt-driven remote control with minimal firmware overhead and broad voltage compatibility.

FAQ

What is the I²C bus speed supported by the PCA9674ATS,118?

The PCA9674ATS,118 supports Fast-mode Plus (Fm+) I²C operation at up to 1 MHz. This enables high-speed communication with microcontrollers while maintaining compatibility with standard I²C protocols. Its 30 mA SDA sink capability ensures robust signal integrity even on buses with up to 4000 pF capacitance - eliminating the need for bus buffers in most applications. The PCA9674ATS,118 achieves this without compromising noise immunity or power efficiency.

How does the quasi-bidirectional I/O architecture of the PCA9674ATS,118 differ from standard GPIO expanders?

Unlike conventional expanders requiring separate direction registers, the PCA9674ATS,118 uses quasi-bidirectional I/O: writing '1' configures a port as input with 100 µA weak pull-up, while writing '0' activates a 25 mA sink for output. This eliminates direction register reads/writes and simplifies firmware. At power-up, all eight ports default to input mode. The PCA9674ATS,118 maintains this behavior across temperature and voltage ranges without external components.

Does the PCA9674ATS,118 support software reset, and how is it executed?

Yes, the PCA9674ATS,118 supports software reset via the I²C General Call address (00h) followed by data byte 06h. Upon receiving this exact two-byte sequence, the device resets all registers to power-on defaults - including port states, interrupt flag, and address configuration. No hardware reset or power cycle is needed. The PCA9674ATS,118 acknowledges only this precise command; deviations (e.g., wrong data byte or extra bytes) result in no action, ensuring safe implementation in live systems.

What is the purpose and access method of the Device ID in the PCA9674ATS,118?

The PCA9674ATS,118 includes a 24-bit read-only Device ID containing 12-bit manufacturer code (NXP), 9-bit part identification (001001011), and 3-bit die revision (000). It is accessed using reserved address F8h: master sends F8h (write), target slave address, Re-START, then F8h (read), then reads three bytes. This enables automated BOM verification and field firmware validation. The PCA9674ATS,118 returns consistent ID values regardless of operating conditions or package variant.

Can the PCA9674ATS,118 drive LEDs directly, and what are the current limits?

Yes, the PCA9674ATS,118 can drive LEDs directly: each of its eight I/O ports (P0–P7) provides 25 mA sink current, sufficient for standard indicator LEDs with appropriate series resistors. Total package sink capability is 200 mA, allowing simultaneous drive of multiple LEDs. The PCA9674ATS,118 also features 5.5 V tolerant I/Os referenced to VDD, enabling safe operation with 5 V LED supplies while interfacing to 3.3 V microcontrollers - no level shifters required.