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How to create a constant current load circuit?
In this application a DAC is used to set a precise current value, but of course this could equally be a simple pot across VCC to Ground. The integrator ramps up or down the gate drive to achieve the desired current through Q1 by adjusting the Ohmic value of RDS.
How to design a simple constant current / constant voltage buck converter?
How to Design a Simple Constant Current/Constant Voltage Buck Converter (1) Assuming a resistive load, Equation 2 governs the voltage at the output: (2) Equation 3 sets the voltage regulation level: (3) As seen in Figure 1, a Zener diode regulates the voltage in CV mode. Using a Zener as a voltage clamp
How does a constant current source power supply circuit work?
This increase in conduction of Q3 allows more current to flow through the load and the 0.1-ohm resistor. If the current flowing through the resistor goes beyond 1 amp, then the voltage across the 0.1ohm resistor becomes greater than 0.1V.
How does a constant current ( CC ) converter work?
A constant current (CC) converter regulates current the same way: the control loop adjusts the duty cycle to maintain a constant output current regardless of changes to the input voltage and output resistance.
Why do we need a constant current circuit?
The values of the Ic = Ib * hfe (Beta) of the transistor. A constant current circuit can also be used as a current limiter. Maxim Semiconductor notes the following on why we need to use a constant current source.
Can a transistor be used as a constant current generator?
In this project, we will build a simple transistor constant current source generator using only 4 components. It is a very inexpensive circuit that can provide 100mA constant current source using a 5V power supply. It will also have a potentiometer to control the current output from 1 to 100mA range.
When do you need a constant current source?
Most occasions in electronics call for a voltage source set to a specific value. However, there are some situations which are more concerned about how many electrons are flowing as opposed to the voltage, and this is what a constant current source does! These are useful for laser and electroplating applications. View full-size schematic.