کنفرانس بین المللی میکروالکترونیک ایران

صفحه اصلی / هفتمین کنفرانس بین المللی میکروالکترونیک ایران

Dual-Mode Gain Control in a Two-Stage Programmable Gain Amplifier

نویسندگان :

Javad Mostofisharq¹

1- Shahrood University of Technology

کلمات کلیدی :

Programmable Gain Amplifier،Gain Control،Low-Power Analog Design

چکیده :

This paper presents a fully-differential dual-mode programmable gain amplifier (PGA) that combines stage-count adjustment with bias current control to optimize gain and power consumption. The proposed architecture consists of a folded-cascode first stage with a differential PMOS input, followed by a simple second stage. In the two-stage mode, the amplifier achieves a maximum gain of 94.2 dB, power consumption of 5.65 mW, a bandwidth of 460 MHz, and a phase margin of 58°. In the single-stage mode, the gain is reduced to 64.8 dB, power consumption drops to 2.91 mW, and the bandwidth increases to 675 MHz. Moreover, a tunable compensation mechanism based on the bias voltage of transistors operating in the triode region enables achieving an optimal balance between phase margin and bandwidth across all modes without requiring additional circuitry. This approach not only reduces the dependency of gain on the number of stages but also allows efficient power management according to the required gain. Simulation results in 0.18 μm CMOS technology demonstrate stable and efficient performance suitable for analog applications requiring dynamic gain adjustment.