Safe-constant-current-source
In the circuit presented, a CMOS operational amplifier regulates the current through a p-channel HEXFET power transistor to ensure a constant voltage across the load resistor (RL). The current can be calculated using the formula: I = VREF/RL. The benefits of this configuration include: (a) in case of component failure, the load current is restricted by RL; and (b) the required overhead voltage for the operational amplifier and the HEXFET is very low.
The circuit employs a CMOS operational amplifier, which is known for its low power consumption and high input impedance. This op-amp is configured to maintain a constant output voltage across the load resistor (RL) by adjusting the gate voltage of a p-channel HEXFET power transistor. The HEXFET acts as a variable resistor, modulating the current flow based on the feedback received from the output voltage across RL.
The current through the load (I) is determined by the reference voltage (VREF) divided by the resistance of RL, ensuring that the output voltage remains stable despite variations in load conditions. This feedback mechanism is crucial for applications requiring precise voltage regulation, such as in power supply circuits or analog signal processing.
In terms of reliability, the circuit design offers inherent protection against component failures. Should the HEXFET or the operational amplifier fail, the load current is limited by RL, preventing excessive current that could damage other components in the circuit. This feature enhances the robustness of the system, making it suitable for critical applications.
Moreover, the low overhead voltage requirement of the operational amplifier and the HEXFET contributes to the overall efficiency of the circuit. This design minimizes power loss, making it advantageous for battery-operated devices or energy-sensitive applications. The combination of these features makes the circuit an effective solution for maintaining stable voltage levels in various electronic systems.In the circuit shown, a CMOS op amp controls the current through a p-channel HEXFET power transistor to maintain a constant voltage across RL The current is given by: 1 ~ VREF/Rl. The advantages of this configuration are: (a) in the event of a component failure, the load current is limited by Rl; and (b) the overhead voltage needed by the op amp and the HEXFET is extremely low. 🔗 External reference
The circuit employs a CMOS operational amplifier, which is known for its low power consumption and high input impedance. This op-amp is configured to maintain a constant output voltage across the load resistor (RL) by adjusting the gate voltage of a p-channel HEXFET power transistor. The HEXFET acts as a variable resistor, modulating the current flow based on the feedback received from the output voltage across RL.
The current through the load (I) is determined by the reference voltage (VREF) divided by the resistance of RL, ensuring that the output voltage remains stable despite variations in load conditions. This feedback mechanism is crucial for applications requiring precise voltage regulation, such as in power supply circuits or analog signal processing.
In terms of reliability, the circuit design offers inherent protection against component failures. Should the HEXFET or the operational amplifier fail, the load current is limited by RL, preventing excessive current that could damage other components in the circuit. This feature enhances the robustness of the system, making it suitable for critical applications.
Moreover, the low overhead voltage requirement of the operational amplifier and the HEXFET contributes to the overall efficiency of the circuit. This design minimizes power loss, making it advantageous for battery-operated devices or energy-sensitive applications. The combination of these features makes the circuit an effective solution for maintaining stable voltage levels in various electronic systems.In the circuit shown, a CMOS op amp controls the current through a p-channel HEXFET power transistor to maintain a constant voltage across RL The current is given by: 1 ~ VREF/Rl. The advantages of this configuration are: (a) in the event of a component failure, the load current is limited by Rl; and (b) the overhead voltage needed by the op amp and the HEXFET is extremely low. 🔗 External reference