Small-Signal Sziklai pair based Tuned Amplifiers with Low Power High Gain

Abstract

New triple transistor topology based two circuit models of PNP driven Sziklai pair small-signal amplifiers have been proposed and analyzed in this paper. First circuit uses matched BJTs while second circuit employs lateral type of unmatched BJTs available at Generic Process Design Kits (GPDK) 180nm technology in Cadence virtuoso Spectre simulation. Transistor Q1 and Q2 in proposed circuit constitute PNP Sziklai whereas transistor Q2 and Q3 collectively represents NPN Sziklai. Matched BJT based circuit works on very low AC input signal 0.1nV-3mV and generates moderate amplifier current gain (9.568), higher amplifier voltage gain (234.899), wider bandwidth (3.8126 MHz), higher power gain (33.517 dB-Watt) with low THD (0.778%) while second circuit based on BJTs available at GPDK 180nm technology, amplifies AC signal ranging between 10 nV-1 µV with higher voltage gain (252.106), moderate current gain (7.6838), wider bandwidth (212.597 MHz), low power consumption (119.596 mW) and low THD (25.3027 u%) than earlier reported commercial BJTs based Sziklai pair small-signal amplifier under triple transistor topology. Excellent thermal stability of the proposed amplifier combined with low level input and output noises over operational temperature range -30^oC ≤T≤+50^oC exemplifies predominant features of these amplifiers. Present article includes detailed physical analysis of related parameters.The layout of the proposed amplifier takes up a small area of 1157.6124 µm2 (12.68µm×12.43 µm) giving same pre and post layout simulation results.