Circuits & Schematics - 19

A resistive DAC in a resistive-feedback loop of an op amp lets you create an analog-digital-analog divider. The resistance, R WA , between the W and A terminals of the Analog Devices AD5293 (Figure 1) decreases linearly with increasing the ...

Designers often use relays as electrically controlled switches. Unlike transistors, their switch contacts are electrically isolated from the control input. However, the power dissipation in a relay coil may render the device unattractive in ...

The article describes an RGB incident light sensor that uses colored LEDs as narrow-spectrum photosensitive elements. In the process of prototyping the RGB sensor, LEDs from the available batches were tested. However, the best results are obtained ...

You can use simple circuits to implement small, regulated plug-in power supplies. In Figure 1, a basic and versatile 5 V supply uses a zener diode and an emitter-follower transistor. You must calculate and design the transformer such that Q 1 is ...

The low-cost percentage-relative-humidity radio transmitter in Figure 1 operates in a cold-storage warehouse for vegetable storage at temperatures of 1 to 5 C. It is generally difficult to collect such data from a low-temperature area with high ...

For symmetrical applications, the circuit of Figure 4 works well. It is made up of the positive limiter already seen and a complementary negative limiter connected in parallel. A single positive reference voltage is used to control both voltage ...

I need a circuit to limit the voltage across some dissipation limited devices. It must: limit the voltage to a maximum of 1.5 V, have symmetrical limiting, be capable of accepting a current of 2 A, and leak less than 100 µA at 1 V. Two Zener ...

It is common practice to use digital open-collector outputs for control units in industrial applications. Using these outputs, you can switch loads, such as relays, lamps, solenoids, and heaters. One possible problem inherent to this type of output ...

Sometimes, you may need to make a DC/DC converter with minor components that can handle small loads. In this article, we are going to make something like that. This DC/DC converter using transistor has only a few components and can handle small ...

On June 12, 2011, the analog EE world lost a star when guru James M. Williams died. Jim’s hundreds of articles, books, and application notes were (and continue to be) a bottomless wellspring of information, inspiration, and the joy of seeing ...