But from there he moves on to the juicy bits. He builds a transistor-based constant current driver, then adds voltage regulation for the circuit as seen in the schematic on the left.

The circuit uses a 9V battery and a voltage regulator to produce a steady power-supply voltage of 5V. From that voltage, the circuit produces a constant sink current, which is independent of the ...

An LED tester can be as easy as a constant-current power supply, and in fact that’s what [Dave]’s first LED tester was, in essence. Set an LM317 circuit up to output 10mA, say, and you can ...

Download this article in PDF format. High-brightness visible-light LEDs (VLEDs) require a constant-current source. This simple, RFI-free circuit takes advantage of the normally-on properties of ...

When you design for electronics applications, such as sensor or amplifier bias supplies or special waveform generators, a controlled constant-current source or sink circuit can serve as a useful ...

The voltage source varies between 0V and 20V, and there are three constant current circuits (from the left): The normal constant current circuit, one with the same transistor in the reversed-collector ...

The voltage source varies between 0V and 20V, and there are three constant current circuits (from the left): The normal constant current circuit, one with the same transistor in the reversed-collector ...