In power-supply circuits, silicon-diode rectifiers are crucial components that allow current to flow in one direction but block it in the opposite direction. They’re like one-way streets for electricity. However, to ensure they work properly and safely, there are two main “rules” or ratings we need to follow:

1. Peak Inverse Voltage (PIV): Imagine pushing against a door that only opens one way. If you push too hard on the wrong side, you might break the door. The PIV is like the maximum force you can push on the door (the diode) in the wrong direction (reverse) without breaking it. If the voltage trying to push through the diode in the reverse direction gets too high, higher than the PIV rating, the diode could get damaged.

2. Average Forward Current: Now, when you open the door the right way with just the right amount of force, it opens smoothly. This is like the diode allowing electricity to flow through it in the forward direction. The average forward current is like the maximum average strength you can use to open the door regularly without wearing out the hinges (the diode) over time. If the diode carries more current than it’s rated for, it can overheat and potentially fail.

A choke input filter in a power supply provides the best voltage regulation with a normal load. The inductance of the choke helps to maintain a more constant output voltage by smoothing out variations in the input voltage, especially under varying load conditions. This results in a more stable output compared to other types of filters.

A three-terminal regulator is a type of voltage regulator that typically includes a voltage reference, an error amplifier, sensing resistors and transistors, and a pass element (like a transistor). These components work together to maintain a stable output voltage. The “three-terminal” designation refers to the regulator’s three connections: input, output, and ground.

In a full-wave center-tap rectifier, the peak inverse voltage (PIV) across each diode is twice the peak voltage of the transformer secondary, which is approximately 2.8 times the RMS voltage. This is because each diode in a full-wave center-tap rectifier conducts for half of the AC cycle and must withstand the full peak voltage in reverse bias during the other half of the cycle.

A shunt regulator is used in applications that require a constant load on the unregulated voltage source. In a shunt regulator, the control element is connected in parallel with the load. It operates by shunting excess current away from the load to maintain a stable output voltage. This configuration ensures a constant load on the unregulated source, regardless of variations in the load.

In a regulated power supply, fuses are components that can conduct both alternating current (AC) at the input before the transformer and direct current (DC) before the output. Fuses are safety devices designed to protect the power supply and connected equipment from overcurrent conditions by breaking the circuit if the current exceeds a certain threshold.

For a three-terminal regulator, important characteristics include the output voltage and the maximum output current it can provide. The output voltage specifies the regulated voltage the device will maintain, while the maximum output current indicates the highest current the regulator can supply while maintaining the specified output voltage.

A full-wave bridge rectifier circuit does not require a center-tapped secondary on the transformer. Instead, it uses four diodes arranged in a bridge configuration to rectify both halves of the AC input waveform. This design allows for efficient use of the transformer and eliminates the need for a center tap, which is required in a full-wave center-tap rectifier circuit.

In a choke input filter power supply, it is advisable to use capacitors rated at the peak transformer voltage as a safety margin. This is because, under certain conditions such as no-load and a failed (burned-out) bleeder resistor, the voltage across the filter capacitor can rise to the peak transformer voltage. Using capacitors rated for this higher voltage ensures they can withstand these potential conditions without failing.

In power supply circuits, the two most common types of filters used are choke input filters and capacitor input filters. Choke input filters use an inductor (choke) as the primary filtering element, while capacitor input filters use a capacitor. Both types have distinct characteristics in terms of voltage regulation, ripple reduction, and efficiency.

A three-terminal regulator is a modern type of voltage regulator that includes a reference voltage, a high-gain amplifier, temperature-compensated voltage sensing resistors and transistors, and a pass-element, all integrated into a single package. The term “three-terminal” refers to the three connections of the regulator: the input voltage, the output voltage, and the ground. This type of regulator is widely used due to its simplicity, effectiveness, and compactness.

In a linear voltage regulator, the conduction of a control element (like a transistor) is continuously adjusted in direct proportion to changes in the line voltage or load current. This allows the regulator to maintain a constant output voltage despite variations in input voltage or load.

When rectifier diodes are used in a high voltage power supply, they may have slightly different characteristics which can result in uneven voltage drops across them. Wiring a resistor and capacitor in parallel with the diodes helps to equalize these voltage drops, ensuring that each diode shares the load more evenly. Additionally, the capacitor helps to smooth out any transient voltage spikes that may occur during operation, improving the stability and reliability of the power supply. Therefore, option C is the correct choice as it addresses both the equalization of voltage drops and the mitigation of transient voltage spikes.

Remote sensing in a linear voltage regulator is accomplished by making a feedback connection directly to the load. This allows the error amplifier within the regulator to sense the actual voltage at the load, compensating for any voltage drops in the wires between the regulator and the load. This ensures that the voltage at the load remains stable and accurate, regardless of variations in the current or resistance of the connecting wires.

In the context of a power supply, the term ‘load resistance’ refers to the resistance presented by the entire load on the power supply. It is calculated as the output voltage divided by the total current drawn, which includes not only the current consumed by the connected load but also any additional current drawn by components like the bleeder resistor.

Increasing the value of the output capacitor in a power supply improves its dynamic regulation. A larger output capacitor provides better filtering and can store more energy, which helps to maintain a stable output voltage during rapid changes in the load or input voltage, thereby enhancing the power supply’s dynamic response.

In a bridge rectifier circuit, both halves of the AC input waveform are used, resulting in a higher average output voltage compared to half-wave or full-wave center-tap rectifiers. The bridge rectifier is more efficient in converting AC to DC, as it utilizes the entire AC cycle, leading to a higher average DC output voltage for the same transformer secondary voltage

In a regulated power supply, four diodes connected in a bridge configuration form a bridge rectifier. This arrangement allows for full-wave rectification, efficiently converting alternating current (AC) from the transformer into direct current (DC). The bridge rectifier is a crucial component in many power supplies, providing a more consistent and higher voltage output compared to half-wave rectification.

A diode connected across the input and output terminals of a voltage regulator in a power supply is typically used to protect the regulator from reverse voltages. This diode can prevent damage to the regulator if the polarity of the supply voltage is accidentally reversed or if a reverse voltage spike occurs. It acts as a safeguard, ensuring the longevity and reliability of the power supply.

In a power supply, if the first choke and the first capacitor inadvertently form a series resonant circuit, it can lead to excessive rectifier peak current and abnormally high peak inverse voltages. This resonance can cause the voltage across the capacitor to rise significantly, potentially damaging the rectifier and other components. Careful selection and design are needed to prevent such resonance in the filter circuit.

A three-terminal regulator is a type of voltage regulator that integrates a voltage reference, error amplifier, sensing resistors and transistors, and a pass element into a single package. This integration simplifies the design and implementation of voltage regulation in electronic circuits, providing a compact and efficient solution for maintaining a stable output voltage.

Filter chokes, used in power supply circuits to reduce ripple voltage, are rated based on their inductance and current-handling capacity. The inductance determines how effectively the choke can filter out the AC ripple, while the current-handling capacity ensures that the choke can carry the load current without overheating or becoming saturated.

Static regulation refers to the ability of a power supply to maintain a constant output voltage despite long-term changes in the load resistance. It is a measure of how well the power supply can adapt to gradual variations in the load over time, ensuring that the output voltage remains stable.

A series regulator is used in applications where efficient utilization of the primary power source is important. In a series regulator, the control element (such as a transistor) is placed in series with the load. It regulates the output voltage by varying its resistance to maintain a constant output voltage, which can be more efficient than shunt regulators, especially under varying load conditions.

Full-wave voltage doublers are designed to use both halves of the AC wave. Unlike half-wave doublers that only use one half-cycle of the AC input, full-wave doublers effectively utilize both the positive and negative half-cycles. This allows them to double the peak voltage of the AC input, leading to a higher output voltage compared to half-wave doublers.