A current divider circuit is an electronic circuit configuration used to split an incoming electric current into multiple branches. It consists of resistive elements connected in parallel, allowing the current to be divided among the branches in proportion to their resistance values.
The principle behind the current divider circuit is Ohm's law, which states that the current (I) flowing through a resistor (R) in a direct current (DC) circuit is given by I = V / R, where V is the voltage across the resistor. Since the voltage is the same across all the resistors connected in parallel, the current flowing through each resistor can be calculated using Ohm's law. The current divider formula for two resistors in parallel is:
I1 = (V / R1)
I2 = (V / R2)
Where:
I1 = Current through resistor R1
I2 = Current through resistor R2
V = Voltage across both resistors (equal for parallel elements)
R1 = Resistance of resistor R1
R2 = Resistance of resistor R2
The ability to split current in a current divider circuit is based on the relative resistance values of the branches. The higher the resistance of a branch, the lower the current that flows through it, and vice versa. The total current entering the parallel branches is divided among the resistors according to their resistance values.
The sum of the currents through the individual resistors is equal to the total current entering the parallel arrangement:
Total Current (Itotal) = I1 + I2
Current divider circuits have various practical applications, including:
Biasing circuits: Current division is used to set specific operating currents in electronic devices like transistors or operational amplifiers.
Current sensing: To measure the current flowing through a particular branch of a circuit.
LED drivers: To control the current supplied to multiple LEDs of different colors or brightness levels.
Power supply distribution: To distribute current among various loads in a power supply system.
It's important to note that current division occurs only when the resistors are connected in parallel. In a series configuration, the current remains the same across all resistors.