I/O EXPANDER I2C 8-BIT 16-VQFN


Bypass caps, pull-ups, strapping resistors, custom silkscreen & more
Design a Custom Board8-bit I/O expander with I2C/SMBus interface operating at 400 kHz, designed to extend GPIO capabilities in embedded systems. Features 8 independently configurable I/O pins with programmable input/output modes, interrupt generation, and open-drain outputs. Ideal for microcontroller applications requiring additional digital I/O without dedicated pins.
This 3×3mm QFN with 0.5mm pitch requires a breakout board to hand-solder reliably—the fine pitch and sub-millimeter pad spacing make direct assembly impractical without professional equipment. The breakout converts the hidden pads to accessible 0.1" spaced pins, enabling breadboard prototyping of energy harvesting and battery management circuits.
ELECTRICAL CHARACTERISTICS
| Manufacturer | Texas Instruments |
| Part Number | TCA6408ARGTR |
| Package | QFN-16 (3×3mm) |
| Pin Count | 16 |
| Clock Frequency | 400 kHz |
| Interface | I2C, SMBus |
| Number of I/O | 8 |
| Output Type | Push-Pull |
| Voltage - Supply | 1.65V ~ 5.5V |
BILL OF MATERIALS
PCB SPECIFICATIONS