Archive for February 2013

Arduino Library For LM95172 Temperature Sensor

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 perform one-shot temperature conversation for low power applications. Continue reading ‘Arduino Library For LM95172 Temperature Sensor’ »

Adding a Barrel Jack And a Switch to Raspberry Pi

I got myself a Raspberry Pi (Model B V2) last month. After having played with it for a while, I have to say that I really like this tiny single-board computer. Since it runs on Linux, you can compile and run your C/C++ code on it. Most popular applications have already been adapted to the ARM architecture and can be run readily on Pi. Unlike some other SBCs, Pi allows easy access to GPIO ports which makes it equally attractive for people who are interested in hardware. Continue reading ‘Adding a Barrel Jack And a Switch to Raspberry Pi’ »

Precision Voltage Adapter For Low Voltage Measurement

A typical 3 ½ or 4 ½ multimeter can measure voltage in the low mV range and current in the low mA range. Voltage measurement in the µV range and current measurement in the nA range are typically only available in the more expensive lab bench multimeters. In this post, I will show you a simple adapter circuit that can be used for precision voltage measurement down to the µV range. Using this circuit along with the current adapter circuit I discussed earlier you will be able to perform most of the low level measurements with a 3 ½ meter. Continue reading ‘Precision Voltage Adapter For Low Voltage Measurement’ »

100K 5% Carbon Film Resistor Value Distribution

It is well understood that resistors are typically binned in such a way that for a given tolerance the actual resistance values are distributed within the specified tolerance but are outside the range of the next tighter tolerance specification. So for instance, when you buy a bunch of 5% 100K resistor, you can expect the values to be between 95K and 99K or between 101K and 105K. Values between 99K and 101K will be missing as they are binned as 1% resistors. Continue reading ‘100K 5% Carbon Film Resistor Value Distribution’ »