7805 voltage regulator in parallel
Every time we come up with power supply circuits, concerns about voltage and current ratings must be a problem, in this post we are going to explain the possibilities of 7805 voltage regulator in parallel connection.
We know 7805 is a linear voltage regulator, in the normal operation, the 7805 regulator needs protecting measures like heat sinks for its good operation.
7805 regulators in parallel
The paralleling of the device means, sharing loads of the devices and uplifting the current in the circuit, in this case, linear regulators 7805 are selected for parallel connection.
But become going to a paralleling of 7805 regulators, we need to know the matching of both 7805 regulator devices, because any slight variation like voltage rating, must affect the whole circuit very badly.
The circuit shown above is the attempt to make a 7805 voltage regulators in parallel, the circuit having two resistors with 7805 ICs and also have two capacitors at the input and an output portion.
The input and output capacitor for filtration and circuit balancing purpose, actually this circuit doesn’t work properly due to the variations in voltage, more specifically this 7805 voltage regulator is not designed to make a parallel circuit.
In this attempted circuit, both the resistor are used to balance the voltage differences, otherwise, two of the regulators acts as master and slave, and after some time one of the regulators get overloaded and damages.
7805 regulator in parallel using diode
The circuit here is a 7805 voltage regulator in parallel, the only difference this circuit has from the first is the two diodes used at the output, 7805 linear voltage regulator device have the voltage variation problem at the output.
This voltage variation problem reduction attempts using diodes in this circuit, paralleling of voltage regulator means, there are no variations in voltage value, but current must be doubled.
This circuit is more successful than the first using only resistor, but this circuit also has an overheating problem and dangerous nature of the whole circuitry
7805 voltage regulator in parallel using transistor
The circuit above will be the high current 7805 voltage regulator circuit, this circuit is also at the 7805 datasheets, we are using tip2955 high current rated transistor.
Multiple attempts to get high current output using a 7805 voltage regulator will be successful with this circuit because in this circuit we don’t have a voltage deflecting problem and damaging of the component at the circuit.
When the input passes through the circuit, a portion of the signal energizes the tip2955 transistor and then the 7805 regulators make a regulated voltage with normal current output, but the tip2955 transistor amplifies the current and given to the output.
The combination of both the outputs of tip2955 and 7805 and voltage standstill with a higher current output.
also read: high current dc power supply
Every circuit in this post need an extra heat sink for its proper operation, both the parallel circuits using resistors and diode have the voltage matching problem because any slightest voltage causes the whole circuit.
And also we mentioned earlier 7805 linear voltage regulators don’t design to make parallel two 7805 ICs.
In light of this problem, the last circuit using a high current transistor is the better option to opt for the high current circuit using a 7805 voltage regulator.