App note: Low cost I2C level translator


2 Diodes, 3 resistors and a transistor here’s Silicon Labs’ low cost solution on voltage level translation. [via]

This applications note discusses a low-cost circuit for I2C level translation. This circuit was developed for the Si701x, Si702x, and Si703x humidity sensors but will work in many applications. This circuit provides I2C level translation from a higher voltage supply, such as 5 V, to a lower voltage, supply such as 1.8 or 3.3 V. In addition, the optional emitter follower circuit provides a low-voltage power supply rail from the higher 5 V supply. Note that some devices allow for higher voltage tolerance on I2C inputs. For example, the Si7034 has a 3.3 V tolerant I2C interface, so the level translation is only required for 5 V I2C designs.

App note: Low cost I2C level translator – [Link]

Arduino, Beaglebone, MCU enclosure with HMI (LCD & keypad)


by Mircea Daneliuc:

An electronics enclosure with HMI ( I2C LCD and keypad) for projects with sensors and relays. Good for any MCU, Arduino, Beaglebone,AVR

I have searched the net high and low to find a professional looking enclosure with an HMI (Human Machine Interface) that I could use in my project involving sensors and relays, but I wasn’t able to find one. Not for a decent price, that is… Most of the Arduino cases or enclosures were nice little boxes with slots for USB and power adapter but with no real functionality, not enabling the microcontroller to relate to the outside world in any way.

Arduino, Beaglebone, MCU enclosure with HMI (LCD & keypad) – [Link]

Tiny and cheap lab generator


Bob build a tiny and easy to build function generator. He writes:

Function generator is a rely useful tool in the lab, a simple version can be build at home, there’s a lot of examples on the Internet, some are much more complex and powerful, but this one is intended to be really simple and cheap. It can be also built-in in some bigger projects that also requires a generator.

The generator can output (only) square signal with adjusted frequency and pulse width. The amplitude may be also modified by soldering different values on the voltage divider on the output, it’s a bit laborious, but if it will be used in digital or microprocessor projects, then there isn’t really need for amplitude adjustment.

Tiny and cheap lab generator  – [Link]

Helicopter Temperature Logger


Rui JC writes:

This circuit is a small “on-board” temperature recorder for RC models.

For those who practice this hobby know that the engine temperature is very important, not only for performance but also to ensure the smooth operation and durability of the engine.

It records the motor temperature of my helicopter in flight 2 times per second and stores it in memory.

Helicopter Temperature Logger – [Link]

EEVblog #754 – Altium Circuit Maker First Impressions

Dave gives his first impression of Altium’s new FREE PCB design tool for the maker community, Circuit Maker.
What are the limitations?
What do you get?

EEVblog #754 – Altium Circuit Maker First Impressions – [Link]

How to use MQ2 Gas Sensor – Arduino Tutorial


by codebender_cc @

The MQ series of gas sensors use a small heater inside with an electro-chemical sensor. They are sensitive for a range of gasses and are used indoors at room temperature. The output is an analog signal and can be read with an analog input of the Arduino.

The MQ-2 Gas Sensor module is useful for gas leakage detecting in home and industry. It can detect LPG, i-butane, propane, methane ,alcohol, hydrogen and smoke.

Some modules have a built-in variable resistor to adjust the sensitivity of the sensor.

How to use MQ2 Gas Sensor – Arduino Tutorial – [Link]

EEVblog #755 – Fluke PM2812 PSU Ebay Score

Dave checks out a Fluke/Philips PM2812 System DC Power supply he scored from ebay for 30 bucks.
Does it work?
Will the bunker hardware tin collection come through?

EEVblog #755 – Fluke PM2812 PSU Ebay Score – [Link]

WIFI plant monitoring system based on Arduino MEGA and ESP8266


by techrm @

Today we are going to show you our first experiment on the Internet of Things. For this purpose, we decided to use an Arduino MEGA instead of an Arduino UNO. That’s because Arduino MEGA has more than one serial port and this fact allows us to use the ESP8266 and the serial monitor at the same time. As written in the title, we’ll see how to monitor some of the most important plant growth factors*. These parameters are: Ambient temperature and humidity Soil moisture and temperature Illuminance

WIFI plant monitoring system based on Arduino MEGA and ESP8266 – [Link]

NRAM is the future



Nantero have announced that their innovative memory technology based on carbon nanotubes has been licensed and is in production in many fabrication facilities around the world. NRAM memory offers a significant speed advantage, (said to be hundreds of times faster than conventional NAND memory) and can be easily scaled to provide terabits of storage capacity which consume very little power.

Key Features of NRAM technology:

CMOS Compatible: Works in standard CMOS fabs with no new equipment needed

Limitless Scalability: Designed to scale below 5nm in the future

High-Endurance: Proven to operate for orders of magnitude more cycles than flash

Faster Read and Write: Same as DRAM, 100s of times faster than NAND

High Reliability: will retain memory for >1,000 years at 85 degrees Celsius or more than 10 years at 300 degrees Celsius

Low Power: Essentially zero in standby mode, 160x lower write energy per bit than NAND

Low Cost: Simple structure, can be 3D multi-layer and multi-level cell (MLC)

NRAM is the future – [Link]

iProtoXi Aistin: Multi-Modular Sensor Platform


Aistin is the product family for creative Internet-of-Things experiences, with Arduino conformance.

The Internet of Things has a different meaning for different people. For some, it means monitoring room temperatures from a mobile phone, whereas for other, it is controlling garden lighting from a laptop computer. For sports-minded people, it might mean logging their heart rate in real-time to a cloud service. Is there a common denominator between this wide range of different applications?

Our answer is Aistin. Instead of functionally limited ready-made IoT-sets, or flexible but unpractical self-wired desktop hassles, we wanted to inspire people to create new mobile products by providing the best that can be achieved with current technology:

iProtoXi Aistin: Multi-Modular Sensor Platform – [Link]