Схемы

Jayapal Ramalingam

Figure 1 gives a simple circuit for the PUSH ON, PUSH OFF function with only a few inexpensive components. In this design, the output is connected to the input of the gadget when you press the push button (PB) once. For the next push, the output is ...

Peter Demchenko

Almost every wall power supply has no indicator showing whether current is consumed by the load or not. It seems that this was a shortcoming that was not only noticed by me: I once saw the solution given in Figure 1. Figure 1. Wall power supply ...

Mark Shill

When probing digital logic levels on a circuit board, locating the indicator of the logic level near the probe tip is convenient, so that you can keep both the indicator and probe tip constantly in sight. When using a handheld DVM or oscilloscope ...

John Betten

Switching power supplies can be notorious noise generators. You should prevent this noise, which is conducted, radiated, or both, from returning to the input source, where it can potentially wreak havoc on other devices operating from the same ...

Stephen Woodward

Figure 1’s negative constant current source has been a textbook application for the LM337 regulator forever (or thereabouts). It precisely maintains a constant output current (I OUT ) by forcing the OUTPUT pin to be the negative V ADJ ...

Stephen Woodward

Tachometry, the measurement of the speed of spin of rotating objects, is a common application. Some of those objects, however, have quirky aspects that make them extra interesting, even scary. One such category includes outdoor noncontact sensing ...

Yongping Xia

A previously published Design Idea describes a practical gadget that has the potential to save a lot with little investment ( Reference 1 ). However, the circuit uses 120 V line voltage and, as such, it is not that convenient for many applications. ...

Deborah Mancuso Donald Schelle

Of the many types of analog filters available to designers, few allow easy adjustments of the filter parameters. The biquadratic, or biquad, filter is an exception, however. You can change that filter's corner frequency (ω 0 ), Q, and ...

Stephen Woodward

LM317 fans will recognize Figure 1 as the traditional LM317 constant current source topology. It closely regulates I OUT = V ADJ /R S by forcing the OUTPUT pin to be V ADJ = 1.25 V positive relative to the ADJ pin. Thus, I OUT = V ADJ /R S to a ...