Tag Archives: Linduino

Linduino is a USB-isolated Arduino

My pals over at Linear Technology have developed the Linduino board to drive their ADCs (analog to digital converters) and DACs (digital to analog converters) as well as temp sensors and other devices. The board is not a clone of an Arduino, that would be pointless for them. Linear Tech sells analog chips, not Maker boards.

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The Linear Technology Linduino board uses the same Atmel chip as a Arduino Uno, but has isoalted USB and more dc power.

So the first and most essential difference is that in addition to the normal shield headers on an Arduino, there is a header that Linear Tech has used for years to drive their demo boards. This computer interface function used to be done with their DC590 interface board. Indeed, the firmware that comes shipped with the Linduino emulates that board, so you can run the original Linear Tech interface program on your PC, and it can’t tell if its the old board or a Linduino.

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The Linduino board will accept all the Shield mezzanine boards for Arduino, but has this extra header to control Linear Tech demo boards as well.

But wait, there is more. So much more. Linear tech also used one of their USB isolators on the Linduino board. This means that the board and what you plug into it are galvanically isolated from the computer you have the USB plugged into. This means you can measure things off a car or an audio system without worrying about ground loops polluting the measurement. Its as handy as a hand-held DVM (digital voltmeter). My former employer Analog Devices also makes bidirectional USB isolators and there may be others that have come to market. You might make your own isolator, but the great thing about the Linduino is that all the system engineering is done for you and the firmware works.

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The Linduino has a LMT2884Y-USB isolator module on it so your PC is not electrically connected to the Linuduino or its Shields or Linear Tech demo boards.

Since Linear Tech is also a power supply chip company, they beefed up the power supply on the board, using a switching regulator to replace the linear regulator on the Arduino. This means you can get 750mA out of the power system. Since a USB can’t supply this much power, that means you have to feed the board with an external wall wart. Now you have the power to drive actuators or other heavy loads.

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Linear Tech also beefed up the power system with a 750mA switching regulator that will not get hot even at full load while dropping for a high input voltage.

Dan Eddelman worked on the Linduino as did Mark Thoren, my pal from Linear Tech. Tomorrow I will plug in the beast and  show how to get it working. I did have a few glitches the first time.

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Mark Thoren, shown here giving his daughter some STEM instruction at the Silicon Valley eFlea, helped develop the Linduino.

Just like Atmel’s demo boards, Linear Tech is selling the Linduino pretty much at cost. This can give you a great foundation to build an isolated data acquisition and control system for cheap. And don’t forget, all the Arduino shields plug into the board and work with the existing libraries and firmware and available open source code. Linear Tech used the same Atmel chip as the Arduino, so this is not just “shield compatible,” is is truly compatible with an Arduino.