Circuits & Schematics Supply - 4

This switching regulator is highly efficient and can be used for AC and DC and requires no reactive L/C components. The regulator can provide a power factor very close to 1. The circuit (see Figure 1) can be used to regulate a heating process with ...

Many portable appliances and other products that must operate from a single cell are restricted to working at very low voltages. It is thus difficult to drive white LEDs that typically have a forward voltage of 3 to 5 V. The ability to flash the ...

A previous Design Idea describes a programmable current source that used a three-terminal LM317 adjustable regulator (Reference 1). Although that circuit lets you program the output current, the load current flowed through the BCD ...

The accurate, high-side, current-sense circuit in Figure 1 does not use a dedicated, isolated supply voltage, as some schemes do. Only the selected transistors limit the common-mode range. The circuit measures the voltage across a small ...

Powering portable telemetry systems for long-term monitoring presents interesting design challenges. Batteries are unsuitable for certain critical applications, and, in these circumstances, designers typically use wireless inductive links to ...

Many applications require a sinusoidal reference voltage synchronized to the ac line voltage. You cannot derive such a reference voltage directly from the ac line because the waveform of the ac line is distorted because of nonlinear loads connected ...

Laser diodes can destroy themselves in a few nanoseconds, so testing the response and stability of a feedback-stabilized laser-diode driver can be expensive. The simulator circuit in Figure 1 shows a typical laser-diode package, which contains not ...

Self-powered isolation amplifiers, which need no external isolated power supply, provide versatile and convenient interfaces in many applications that require galvanic isolation of the signal source. Examples of such applications include circuits ...

The circuit in Figure 1 is a quasi-linear regulator. It functions as a source follower for input voltages greater than a preset level, determined by VR 3 . For input voltages lower than the preset level, the pass element, Q 2 , operates as a ...

When parts have been around as long, and in such widespread use, as the venerable LM317 and LM337 (and their siblings), you tend to think every trick that can be played with them is already in the (data)book. So, when the question arose whether ...