What is the main function of the high-voltage circuit?

• A. Provides high voltage required to accelerate electrons and generate x-rays
• B. Provides low voltage to the display
• C. Converts AC to DC for motor
• D. Regulates filament current

Answer: (A)

The high-voltage circuit’s job is to provide the large potential difference across the X-ray tube, accelerating electrons from the heated filament toward the anode to produce X-rays. This kilovoltage not only drives photon production but also sets the beam energy, influencing image quality and patient dose. The filament current, which heats the filament to emit electrons, comes from a separate low-voltage circuit. Other options describe circuits serving displays or motors and don’t control the tube voltage or electron acceleration.