Re: What are special type of resistors like poly , n + & p + resistors etc. ? thanks
If a resistor is required in a integrated circuit than it is fabricated by a poly-silicon layer or by diffusion of n or p type impurities.
Poly-silicon resistors can be fabricated with high precision but requires larger area. High precision resistor are required in analog circuits as even small variation in resistor value have large impact on circuit characteristics.
Diffusion resistors have less precision but requires lesser area. The value of resistor can be varied just by changing doping densities. These can used in digital circuits.