20 Topics.
0 of 9 Concepts Done
Asked in UPSC PrelimsUPSC 2007
What to Study: Where do semiconductors sit between conductors and insulators, and why? Understand the band gap. How does a semiconductor's conductivity change as temperature rises, and how is a metal different? Know silicon and germanium as examples, and the difference between intrinsic and extrinsic semiconductors.
What to Study: What is doping? Know which kind of dopant makes an N-type semiconductor and which makes a P-type, with an example of each, and the majority carrier in each type. Understand what a hole is. Does a doped crystal carry an overall electric charge?
What to Study: What makes a semiconductor "wide-bandgap" or "compound"? Understand why gallium nitride and silicon carbide suit high power, high frequency and high heat better than silicon. Know their uses (EV power electronics, chargers, 5G, radar). Which compound-semiconductor projects has India approved under the India Semiconductor Mission, and where?
What to Study: How does a p-n junction form, and what is the depletion region? Understand what forward bias and reverse bias each do to current flow. Is one-way flow of current a property of a plain semiconductor, or of the junction?
What to Study: How many terminals does a diode have, and in which direction does it let current pass? Understand how a diode rectifies alternating current into direct current. Remember its other uses: as a switch, as a voltage regulator (Zener diode), as a light source (LED) and as a light sensor (photodiode).
What to Study: Understand the jobs a transistor can do in a circuit. Remember the terminals of a bipolar transistor, and that a MOSFET, the type used in chips, names its terminals differently. What does an amplifier do to a signal, and why are transistors used to build it?
What to Study: What are an integrated circuit, a microprocessor and a system-on-chip (SoC)? Understand what Moore's law says and why it is slowing. Does the "nanometre node" of a chip, such as "3 nm", measure a real physical length?
Asked in UPSC PrelimsUPSC 2026
What to Study: Match each processor to its developer and its purpose: SHAKTI, Vikram 3201 and DHRUV64. Which is meant for space use? What is RISC-V, which of the three processors are built on it, and why does an open instruction set matter? Be careful with claims of being the "first", since they differ between reports.
What to Study: How do a CPU, a GPU and an NPU differ in what they are built to do? Understand why AI workloads run on GPUs and accelerators. Know the Nvidia RTX Spark as an example of an AI chip for personal computers, and what makes its processor design different from the usual PC chips.