Схемы

Antonio Muñoz Arturo Mediano

The basis for this Design Idea is a circuit that uses three resistors and a microcontroller-I/O pin to work as input high impedance or output to independently drive two LEDs ( Reference 1 ). The idea sounded good for this design, mainly because of ...

Testing the system Testing was done at various sunlight intensities. For any given sunlight intensity, V PV , I PV , V M , I M , etc., are measured. Figure 5 shows the variation of PV power (P PVON ), converter power (P M ), and total power (P TOT ...

Vijay Deshpande

The PV-pushback-effect with solar panels can control backup power and provide constant light output. Solar day lamps (SDLs) are made by simply connecting an LED array to a solar photovoltaic (PV) panel. SDLs represent a highly cost-effective way of ...

Peter Demchenko

Junction field-effect transistors (JFETs) usually require some reverse bias voltage to be applied to a gate terminal. In HF and UHF applications, this bias is often provided using the voltage across the source resistor R S (Figure 1). Figure 1. ...

When a system's specifications call for a lowpass filter with a steep frequency-cutoff characteristic, an engineer can opt for a “brick-wall”- filter design that features a sharp transition band. For example, in an FM ...

Nick Cornford

While an internal, rechargeable lithium battery is usually the best solution for portable kit nowadays, there are still times when using replaceable cells with an external power option, probably from a USB source, is more appropriate. This DI shows ...

Stephen Woodward

Self-heated transistors used as thermal air flow sensors are a particular (obsessive?) interest of mine, and over the years I must have designed dozens of variations on this theme. Figure 1 illustrates one such topology seen here (Reference 1) ...

Stephen Woodward

Integration of analog circuitry with digital logic often requires the addition of an extra supply rail or two. The excellent PSRR of precision op-amps (typically 100 dB) makes them unfussy about power rail variations. This simplifies power supply ...