Free Circuit Diagram

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 [...]

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 [...]

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 [...]

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: [...]

Notch filter is known as band-cut filter or band-reject filter. The fuction of this filter is to remove some frequency portion of a signal. The schematic diagram of this filter circuit, a second order notch filter is depicted in the figure below. The formula is actually complicated, but by taking the R3=R4 and [...]

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  [...]