Free Circuit Diagram

This is a simple circuit that can be used to convert a 4-20mA signal to a 0V to 5V analog voltage. It is ideal conversion to digital with an analog-to-digital converter (ADC). In this circuit, a current-sense amplifier (IC1) is used to monitor the loop current. To generate a ground-referenced output that ranges from 0V [...]

Current loop interface has been widely used in industrial environment because it’s robustness. Noise resistance and fail detection capability  made it suitable for long distant transmission in harsh environment. This circuit provide current loop transmitter for temperature sensor. Here is the circuit’s schematic diagram: The temperature measurement is done by LM35 temperature sensor [...]

High voltage current sensing/monitoring can be designed using LTC6101 op-amp. The following current sensing circuit is capable of measuring electrical current in 500 volts system. Here is the schematic diagram of the circuit: Two external Mosfets is added to hold off the voltage, allows the LTC6101 to be connected to a very high [...]

If you have a digital voltmeter, or any voltmeter with millivolt resolution and high input impedance, then you can use this temperature-to-voltage adapter circuit to measure room temperature. Here is the circuit’s schematic diagram: Note that the voltage output of this circuit is floating, not referenced to ground. You have to [...]

In some temperature-sensing applications there are some problems caused by the placement of sensors on location where the potential is very different from that of the data-acquisition-system common. So the operating temperature sensor must be isolated from its data-acquisition system galvanically.  And the power’s source for the sensor was isolated. This circuit is designed to [...]

Introduction Interfacing humidity sensor can be difficult because of the sensor’s drive requirement and their wide dynamic range.  We can customize the circuit to obtain reasonable accuracy within the chosen range by carefully selecting the devices that comprise the analog front end. Here  we present a case study to design analog signal conditioner for [...]