As shown in figure "3" of the illustration,...

🔍 Key Concepts

• Diode logic vs. diode–transistor logic (DTL) – look at whether a transistor is included in the circuit and what it does to the output. • How a NAND truth table compares to a NOR truth table (which inputs give a LOW or HIGH output). • How diodes wired from the inputs toward the junction behave when inputs are HIGH or LOW (which states cause current to flow and pull the junction low).

💭 Think About

• For circuit 3, trace what happens at the transistor base and the output when both A and B are HIGH, when one is HIGH and the other LOW, and when both are LOW. • Ask yourself: are the diodes being used to create an AND condition at the transistor base, or an OR condition? Then notice that the transistor and load resistor invert that result. • Compare the behavior you find to the truth tables of NAND and NOR gates to see which one matches.

✅ Before You Answer

• Verify whether a transistor is present and actually switching the output (this points to diode–transistor logic rather than pure diode logic). • Check which input combinations make the output LOW vs HIGH, and match that pattern to either NAND or NOR logic. • Confirm that the diodes are arranged so that any LOW input or any HIGH input will clamp the node in a particular direction; this tells you whether the diode network is implementing AND or OR before inversion.

As shown in figure "3" of the illustration, which statement is true? See illustration EL-0099.

The circuit is for a NAND gate using diode logic.

The circuit is for an NOR gate using diode logic.

The circuit is for an NAND gate using diode transistor logic.

The circuit is for an NOR gate using diode transistor logic.

🔍 Key Concepts

💭 Think About

✅ Before You Answer