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Can you use a voltage regulator as a current source?
Depending on the regulator you can indeed also use a fixed regulator as a current source. The only disadvantage is that the voltage drop across the shunt resistor (R2 in your schematic) will be higher.
What is a constant current regulator?
The constant current regulator (CCR) is a simple, economical and robust device designed to provide a cost effective solution for regulating current in LEDs (similar to Constant Current Diode, CCD). The CCR is based on Self-Biased Transistor (SBT) technology and regulates current over a wide voltage range.
Can a fixed voltage regulator be used as a current source?
Depending on the regulator you can indeed also use a fixed regulator as a current source. The only disadvantage is that the voltage drop across the shunt resistor (R2 in your schematic) will be higher. That LM1086 looks suitable to me but it will drop 3.3 V (the regulator’s set voltage) across R2.
Can a shunt resistor be used as a current regulator?
The hardware outputs a variable voltage depending on the voltage drop across the shunt resistor. Knowing this means that many of use will instinctively think of using a constant voltage source and a well chosen resistor to turn a small voltage regulator into a current regulator.
What is the output current of a linear regulator?
Consider that if the regulator output voltage is V and it’s feeding a resistor R, the output current must be V/R. But since this is a linear regulator, the input current is Iout + Iq (quiescent current, from the datasheet), and any excess voltage is dropped across the regulator.
Is the LM317 a constant voltage regulator?
That’s because the LM317 is secretly just a 1.25V linear regulator. Move R2 to the input of the regulator -Connect pin2 to gnd.Pin 3-output to the load. You have a simple and reliable current limited constant voltage source. Set current limit by value of R2.