LM92 is a 12-bit + sign temperature sensor from Texas Instruments. This sensor operates on the I2C interface and can achieve an accuracy as high as ± 0.33 °C within the typical temperature measurement range. I created a comprehensive Arduino…
We can send and receive commands wirelessly with Arduino by using these cheap RF data link transmitters/receivers. I like these RF modules because they can be hooked up to pretty much any device that supports serial communications (e.g. devices equipped…
In my previous post, I showed my design of a dual tracking ±30V linear power supply. My goal was to use the transformer (28V+28V, center tapped) from an old Deltron W127G open-frame power supply and build a lab supply that…
A while back I built a simple constant current electronic load using an aluminum HDD cooler case as the heatsink. While it was sufficient for a few amps’ load under low voltages, it could not handle load much higher than…
TI’s TLV5620 is a budget 4-channel 8-bit DAC. While it is designed primarily for running with a power supply between 3V and 3.6V, it can be powered by 5V as well given its wide supply voltage range. With a TL431…
Arduino‘s (ATmega328P) PWM outputs via analogWrite can be conveniently turned into analog voltage levels through the use of simple RC filters. Since the PWM outputs are not isolated, using them to drive other devices directly could be potentially dangerous. This…
After I completed the filament driver and the circuit to drive the multiplexed VFD segments, it is time to finish the VFD clock project I had in mind earlier.
In my previous post, I showed a simple vacuum fluorescent display filament driver built using a 555 timer and a custom hand-wound, center-tapped toroidal pulse transformer. And as promised in my earlier comment, I am going to show you the…
I did a teardown of a BK Precision 4011 5MHz function generator a few weeks ago. Like most of basic function generators in old days, BK 4011 does not offer frequency sweep as an option. What it does include is…
Last week, I discussed the construction of a network-capable temperature and humidity sensor using SHT21 and ENC28J60 with an ATmega328P microcontroller. In this post, I will show the results obtained so far and the techniques used to chart the data.
I did a project on temperature/humidity logging a couple of years ago. In that project I logged the temperature and humidity readings in my basement lab over the course of a year. One issue with the approach I took back…
LM95172 is a 13 to 16 bits wide temperature range automotive-grade temperature sensor in a ceramic SOIC package. Besides its wide range temperature measurements capability (-40 Celsius to 200 Celsius), it can also be programmed to trigger over-temperature/under-temperature alarms and…
I bought a used Keithley 196 bench multimeter a few weeks ago. This is a 6 ½ digit 3,030,000 counts meter, capable of measuring voltages down to 100nV and currents as low as 100nA. It can also be used to…
ADS1224 is a 24-bit delta-sigma analog-to-digital converter with 4-channel differential inputs multiplexer. This ADC chip offers a 20-bit effective resolution (6 to 7 digits of resolution in full scale), which makes it ideal in high-resolution voltage measurement applications.
I picked up an AD9850 DDS module on eBay an couple of weeks ago and decided to build a MCU controlled DDS function generator with it to replace my crude frequency generator I built earlier.