Free Circuit Diagram

This is pressure sensor signal conditioning circuit. It is simple and inexpensive circuit because it has small geometry and simple pressure sensor. It just uses a single Operational Amplifier. This circuit obtain power from from 3-V battery. To work properly this circuit must work in  0 C to 50 C temperature range. Here is the [...]

To obtain an accurate pressure value, we must remove the offset errors. There are  many basic circuit designs that is used to remove the offset errors. This  circuit uses three method to remove the offsets errors, they are symmetrical offset trim, asymmetrical offset trim and amplifier gain adjustment. Here is the circuit: [...]

Silicon pezoresitive-bridge pressure transducer (SPPT) is very popular in medical, industrial, environmental, and automotive pressure sensor application. The general architecture of SPPT uses a thin micromachined silicon diaphragm incorporates a implanted piezoresitive Wheatson-bridge strain-gauge. The transducer design allows only a small diaphragm deflection sin it has limited elasticity, and this produces only a very [...]

You can use a humidity sensor to give an alert of boat leakage, or when your books start being flooded by heavy rain attack on your broken roof, or anything you can imagine. A simple humidity sensor (a humidity probe) can be constructed using two copper wires placed as close as possible to each other, [...]

For any electrically conductive liquid level measurement, this single chip circuit is very compact and simple. This circuit is an ac excited fluid level sensor, which uses alternating current to provide biasing for the sensor probe to avoid electrolysis of the probes.  This ac excitation makes the sensing probe has longer lifetime. This circuit can [...]

Designing passive crossover network for your speaker system is easy, just like what shown in our previous crossover design article, but now we can design many types of crossover even easier using online crossover design tool. The crossover schematic diagram here is an example  with a case of 10 kHz high corner frequency, 1250 Hz  [...]