articles

How To Add 128 Extra I/O Ports Without Upgrading Your MicroComputer!

Tuesday, March 22, 2016

Do you want a crazy amount of Digital Input and Output (Digital I/O) in a small space without upgrading your microcomputer?

You can achieve this with the DIGIO-128 super-mega digital I/O card. The DIGIO-128 lets you add 128 GPIO (General Purpose Input/Output) lines, thanks to the Microchip MCP23017, which is a 16-bit general purpose parallel I/O port expander with I2C two wire serial interface and 28-pin ICs that supports 100kHz and 400kHz.

The 128 digital I/O lines are accessed via 8 I/O connector pins, each offering 16 digital I/O, 2 power and 2 ground. The distance between the pin connectors (pitch) is 0.1". DIGIO-128 uses 8 Microchip MCP23017 in total, offering 16 inputs or outputs each and a maximum of 128 extra I/O ports.
You can operate 128 LEDs directly by the I/O pins one at a time as each I/O has a 25mA sink/source capability, which means DIGIO-128 can support a relatively low impedance load, providing 25mA per pin of current from the output pin for driving a logic high output, as well as permitting 25mA of current to pass through the pin to the microcontroller's ground pin, when driving the output low. The DIGIO-128 also uses a single 4-pin host interface connector for ground, power, clock and data.

The DIGIO-128 is compatible with microcomputers like the Raspberry Pi, BeagleBone Black and Arduino as it's able to run at either 3.3V or 5V, thanks to the other chip on-board (Microchip 24LC024), which is a 2Kb Serial EEPROM with a voltage range of 1.7V to 5.5V (and 256 x 8-bit memory).

What's great about the DIGIO-128 is that it allows to save board space and preserve valuable digital I/O pins for other uses as you can run just four wires with these ICs.

See more:

You Might Also Like

0 comments

About Gadget Explained

Connect With Gadget Explained