Circuits & Schematics Measurement - 19

Jeff Magee It is emphasised that this should not be used for medical purposes. Displays your pulse rate, blood oxygen level and a moving graph of each heart beat, the photoplethysmogram (PPG). About this project This project implemented on an ...

Tirdad Sadri Nejad Hackster.io With a code size of 1 KB on an ATtiny13A MCU, this tiny module measures voltages up to 22 volts and current up to 5 amps. There are a lot of so-called USB doctor modules which are used for monitoring currents flowing ...

The basic VFC (voltage-to-frequency converter) in Figure 1 comprises an integrator (IC 1 ) and a Schmitt-trigger circuit (IC 2 ). The integrator converts the dc input voltage, V IN , to a linear voltage ramp, and the Schmitt trigger sets the limits ...

Guido Nopper Electronic Design Incremental-rotation or linear encoders are very common, but normally they do not provide a direction signal. This design shows an easy way to detect forward or reverse direction. Incremental encoders normally provide ...

John Wynne EDN In applications in which you need remote measurement of temperature with a three-wire RTD (resistance-temperature detector), it is important to eliminate the ohmic errors caused by the excitation current flowing through the wiring ...

Shyam Tiwari EDN Using ac-line power sources and batteries for remote humidity sensors is undesirable because these sources can be troublesome if you mount them in inaccessible points, such as smokestacks, cold-storage chambers, or darkrooms, where ...

TEC (thermoelectric-cooler) temperature-control systems often have limited stability. The causes of these limitations are the thermal properties of the system, not the performance of the control electronics. Real-world thermal-control systems incur ...

Most engineers know about the solid-state refrigerators called Peltier devices or, more commonly, TECs (thermoelectric coolers) and how they can actively cool temperature-sensitive electronic components, such as optical detectors and solid-state ...

Alan Erzinger EDN Most object-sensing systemshave problems detecting the presence of an object. The system in Figure 1 uses an oscillator to ease detection problems and allow sorting. The oscillator reduces power dissipation in the photodiode by ...

In theory, the design of current sensing circuitry, typically based on simple measurement of the IR voltage developed across a resistor placed in series with the current to be sensed, looks like an easy task. In theory. But in practice, ...