What kind of gate must be used if a digital output must deliver more current than is typical?

• A. And gate
• B. Or gate
• C. Buffer
• D. Nand gate

Answer: (C)

When a digital output needs more current than a typical gate can supply, you use a buffer to boost drive strength without changing the logic signal. A buffer is designed to preserve the input logic level while providing a much lower output impedance, which lets it source or sink more current to drive loads like LEDs, relays, or long cables. Using a buffer keeps the signal true to its original value, unlike other gates whose primary purpose is to perform a logic function (like AND, OR, or NAND) and could invert or alter the signal if used for current boosting. So the buffer is used specifically to increase drive capability while maintaining the correct logic level.