onsemi

PCA9535EDTR2G

PCA9535EDTR2G Description

The PCA9535EDTR2G from onsemi is a 16-bit I²C/SMBus I/O expander designed for low-voltage bidirectional communication in embedded systems. Operating within a 1.65V to 5.5V supply range, it supports a 100 kHz clock frequency, making it suitable for interfacing with microcontrollers and peripheral devices. This surface-mount IC comes in a 24-pin TSSOP package and is RoHS3 compliant, ensuring environmental safety. Though marked obsolete, it remains a reliable choice for legacy designs requiring 16 configurable I/O ports with 10mA sink/25mA source current capability. Its interrupt output feature minimizes polling overhead, enhancing system efficiency.

PCA9535EDTR2G Features

• 16 I/O Pins: Configurable as inputs or outputs with individual polarity inversion.
• Wide Voltage Range (1.65V–5.5V): Compatible with mixed-voltage systems.
• I²C/SMBus Interface: Supports standard (100 kHz) communication protocols.
• Interrupt Output: Reduces MCU load by signaling input state changes.
• Power-On Reset (POR): Ensures predictable startup conditions.
• High Drive Strength: 25mA source/10mA sink current per I/O.
• Low-Power Design: Ideal for battery-operated applications.
• Tape & Reel Packaging: Optimized for automated assembly.

PCA9535EDTR2G Applications

This I/O expander excels in scenarios requiring port expansion or interfacing multiple sensors/actuators, such as:

• Industrial Control Systems: PLCs, HMI panels, and sensor hubs.
• Consumer Electronics: Keypad controllers, LED dimmers, and smart home devices.
• Embedded Systems: GPIO extension for microcontrollers (e.g., Arduino, Raspberry Pi).
• Automotive Modules: Non-critical functions like lighting or seat controls.
• Medical Devices: Low-power peripheral management in portable equipment.

Conclusion of PCA9535EDTR2G

The PCA9535EDTR2G offers a robust, flexible solution for I/O expansion in mixed-voltage environments, combining ease of integration with interrupt-driven efficiency. While obsolete, its high current drive, wide voltage range, and I²C compatibility make it a pragmatic choice for legacy or cost-sensitive designs. Engineers should evaluate alternatives for new projects but can leverage this IC for maintenance or backward-compatible upgrades.