Circuits & Schematics - 16

In a three-phase ac system, a power source with three wires delivers ac potentials of equal frequency and amplitudes with respect to a zero-potential wire, each shifted in phase by 120 from one wire to the next. Two possibilities exist for ...

The MOSFET in Figure 1 is used as both a heater and a temperature sensor in a thermostatic circuit. Figure 1. Circuit diagram for using a MOSFET as a thermostatic heater. The circuit can be used as a tiny thermostat for some biological structures ...

The advent of instrumentation amplifiers with digital gain switching offers obvious advantages, such as board-space saving, higher reliability because of fewer solder joints, and lower total cost. These valuable features stem from the fact that the ...

A self-biasing thermistor circuit had an overall dominant thermal/ electrical time constant as small as 25 msec but had a significantly rounded response following a square (thermal) input pulse of 100 msec; the source was a pulsed blue LED. A ...

In the AGC circuit of Fig 1, a 4-quadrant analog multiplier (IC 1 ), an amplifier stage (IC 2 ), an active, full-wave rectifier (D 1 , D 2 , R 4 -R 7 , and IC 3 ), and an integrator (IC 4 ) accomplish automatic gain control of V IN ’s ...

Most battery chargers comprise nothing more than a series-pass regulator with current limit. In solar-powered systems, you can’t count on sufficient headroom to keep a series regulator alive, so a shunt method is preferred. A simple shunt ...

The sample and hold circuit (Figure 3) is considerably more complex than the oscillator. This is unfortunate but unavoidable. It's the S/H that gives this design its speed (fast settling time) and very low distortion, and it's very unlikely ...

Introduction As discussed in the article [ 1 ], although a sinewave is the simplest possible waveform, it is also one of the hardest to generate in pure form. Any impurity represents distortion, and that means added harmonics that make very low ...

Solid-state-lighting applications are quickly moving into the mainstream. Although they are more efficient, the LEDs that produce the low-cost light often require a complicated driver circuit. Testing the driver circuit using LEDs, although easy, ...

The linearity of triangular waveforms makes the triangular- wave generator useful in sweep circuits and test equipment. For example, switched-mode power supplies and induction motor-control circuits often include a triangular-wave oscillator as ...