Automatic gain control circuit

Automatic gain control circuit. Here is a simplified version of that using Simulink with abs(x) used as an ideal CN-0390 Circuit Evaluation Board (EVAL-CN0390-EB1Z) Design and Integration Files Schematics, Layout Files, Bill of Materials CIRCUIT FUNCTION AND BENEFITS The automatic gain control (AGC) circuit is useful in multiple applications such as amplitude stabilization of a synthesizer, controlling output power in a transmitter, or optimizing 2 days ago · suvi020. I'm trying to build an automatic gain control circuit but I don't really know where to start. The core of the Aug 16, 2018 · In order to achieve the wide range of infrared gas detection system, an automatic program-controlled gain circuit system is designed based on MCP42010. Figure 2: automatic gain control block diagram. Question: 1) How does the automatic gain control generate a negative voltage to the gate of the FET? 2) Where is the Q-point for the JFET in circuit? 1) How does the automatic gain control generate a negative voltage to the gate of the FET? 2) Where Oct 31, 2020 · An Automatic Gain Control Circuits for the Microphone Read-out Integrated Circuit. To achieve low Feb 1, 2013 · A differential automatic gain control (AGC) circuit is presented. Circuit performance, as measured by the AGC figures of merit described in this circuit note Nov 4, 2022 · Analog Devices, CN3090, “20 GHz to 37. AGC is used in data processing to improve the visibility of seismic data in which attenuation or spherical divergence has caused amplitude decay ( Figure 5. Due to the high temperature stability of the AD8318, this circuit provides stability over temperature because the AD8318 radio frequency (RF) detector ensures the Dec 10, 2002 · A high performance automatic gain control (AGC) circuit is proposed in this paper. Nov 22, 2016 · Learn how AGC works and why it is important for RF receivers. The circuit can vary its gain according to the input signal level and is used for amplifying microphone signals. Dec 4, 2009 · The circuit is used to automatically control the volume levels of cassette recorders, audio tape recorders, amplifiers or radio devices. The automatic gain control system aims to detect distortion at the output of an amplifier, decrease the gain, and then recover the gain to the previous level when the distortion has subsided. A linear AGC suffers from the dependence on the input signal amplitude which results in variable convergence times, thus limiting its utility in practical applications. Dec 1, 2008 · Automatic gain control (AGC) circuit is an indispensable. Jun 1, 2004 · IMPLEMENTATION CONCERNS In order to create a microcontroller-based automatic-gain-control system, it's necessary to mimic the two basic analog-circuit building blocks: the rectifier and the Jun 2, 2002 · Automatic Gain Control ACG - This project is a digital Automatic Gain Control (AGC) system using a PIC16F876 MCU. When the input level reaches a lower threshold, e_0 e0 , the AGC becomes active and the output level Nov 7, 2022 · In this way, the dynamic range and signal-processing performance of the input stage and amplifier are optimally used. The loop consists of a controllable gain element, a detector, a stable reference and a comparison Automatic Gain Control (AGC) AGC is a system that controls the increase in the amplitude of an electrical signal from the original input to the amplified output, automatically. Feb 24, 2023 · Automatic gain control (AGC) is a technique used in electronics and telecommunications to automatically adjust the gain of an amplifier circuit in response to changing input signal levels. It is parallel resistor to R2 and togheter with Jun 26, 2009 · Automatic gain control (AGC) is unavoidable part of radio receivers. 35 μm standard CMOS technology. This paper proposes a large dynamic range automatic gain control (AGC) circuit based on May 12, 2021 · 5. Jul 25, 2010. This paper presents the design of an all-digital high-dynamic AGC, which is suitable for high-frequency software radio receivers that use baseband signal processing. A linearized feedback loop amplitude model is used to design the AGC and the performance is verified with SPICE May 21, 2008 · The generalized design of Automatic Gain Control (AGC) circuits that have constant settling time is described. 13/spl mu/m technology. In this article, we discussed a few different kinds of AGC. The automatic gain control circuit controls the output power level of a transmitter and generates a well controlled ramp-up and ramp-down of the transmitted signal. I used U2B to give no amplification for peak input voltages of 0. #1. This circuit is a building block of another project I am working on. I configured the JFET like that to change its resistance value automatically and affect the gain of the amplifier U2A. Automatic Gain Control: A circuit that modulates an amplifier's gain, in response to the relative strength of the input signal, in order to maintain the output power. 6-V supply voltage with threshold voltage V th of 0. May 12, 2021. Experiments of the implemented AGC circuit shows that Automatic Gain Control or AGC. Each of the major components of the AGC circuit is modeled and the criteria to obtain a gain settling time independent of the absolute gain are determined. No lowpass Mar 15, 2012 · The role of an Automatic Gain Control (AGC) circuit is to provide relatively constant output amplitude regardless of the signal variations at its input. I took a more “practical” route instead, and did some experiments with a model I’ve built Application of automatic gain control for radiometer diagnostic in SST-1 tokamak. Gain control is necessary to adjust the receiver sensitivity for the best reception of signals of widely varying amplitudes. incoming signal varies over a w ide dynamic range, such as . Delayed Automatic Gain Control: Simple AGC is clearly an improvement on no AGC at all, in that the gain of the receiver is reduced for strong signals. Jan 3, 2023 · This AGC circuit is designed using feedforward technique and the output level of −20 dBm ± 2 dBm is maintained. Aug 31, 2023 · An Automatic Gain Control (AGC) is the amplitude analog of a Phase Locked Loop (PLL). The generalized design of Automatic Gain Control (AGC) circuits that have constant settling time is described. An AGC circuit, a closed-loop feedback system, is shown in Figure 1. It includes discussions on loop gain, regulation and the relation between loop parameters and output level stability. The peak detector and comparator compare the –1. So we proposed an intelligent AGC system using fuzzy logic and The paper presents the general theory of automatic gain control (a. Sep 1, 2009 · The analog gain control loop is an attractive solution for simple signals. The paper presents the general theory of automatic gain control (a. i designed an Automatic Gain Control (AGC) circuit using the LT1498 op-amp and a BFW10 N-channel JFET, achieving a perfect output (in LTspice simulation). AGC circuit utilizes feedback to maintain a stable signal-power level within the receiver even though the signal level varies in a big range. Junction field-effect transistors (JFETs) operating in nonsaturation regions, which are equivalent to voltage-controlled resistors, determine the gain of the Apr 26, 2024 · A critical part of the solution involves circuit design strategies, such as the implementation of automatic gain and bandwidth control. 28V to 0. Modern receivers combine analog and digital signal processing. Figure 13-76. Circuit operation of this new peak-detector demonstrates superior performance to the conventional one, by keeping and tracking the peak of the input signal at the same time. A 30W power amp for either the PCS, iDEN or CDMA frequency bands. I do the simulation with the program LT-Spice. A simple AGC could consist of rectifying x(t) using a diode circuit, then lowpass filtering the rectified signal, then comparing the filtered signal with a desired amplitude, and adjusting the gain using a four quadrant multiplier. The automatic gain control circuit solves this problem by monitoring the output amplitude and adjusting the loop gain so the sinusoid amplitude is stable. Field effect transistors T1 is used as a variable resistance. October 2020. 5-5V). 356V or above. 5 GHz, RF Automatic Gain Control (AGC) Circuit” Jun 1, 2010 · In addition automatic gain control circuit [7], programmable analog circuits [8], oscillators [9][10], basic arithmetic operators [11] are the applications which memristors have already been used May 27, 2022 · A large dynamic range automatic gain control circuit based on variable gain amplifier VCA810 to enhance the detection distance and decrease the false alarm rate in EAS system, which is composed of controllable amplification circuit, comparison circuit, detection circuit and voltage adjustment circuit. A system analysis technique is developed based on recently published physical memristor models and unique properties of the passive device. : Automatic gain control for ECG 3 3 12 3 R Vout Vin RR R = ++ (5) The circuit works as balanced full-wave rectifier after making the gain of the inverting amplifier equal Aug 1, 2016 · The circuit used is in the design of a compact low-voltage low-power automatic gain control circuit (AGC) with a control range of ~30 dB . Automatic Gain Control ADC Based on Signal Statistics for a Cognitive Radio Cross-Correlation Spectrum Analyzer; Automatic Gain Control (AGC) Usage of the Automatic Gain Control Circuit; AN-934 60 Db Wide Dynamic Range, Low Frequency; Design and Operation of Automatic Gain Control Loops for Receivers in Modern Communications Systems Oct 14, 2019 · Automatic gain control with HMC624 and PSA4-5043+. The method developed works with arbitrary monotonic nonlinear functions in the gain control characteristic of the variable gain Aug 15, 2016 · Automatic Gain Control is widely used to smooth the signal of communication recievers. Each of the major components of the AGC circuit is modeled and the criteria to obtain . With the huge development of communication systems during the second half of the XX century, the need for selectivity and good control of the output signal's level Mar 3, 2020 · An Automatic Gain Control (AGC) circuit is a circuit that is designed to maintain a constant output signal level after amplification, despite variations in signals at the input of the amplifier or system. i was thinking about using one of those digital pots to alter the gain of an opamp. 3 mW and occupies only 0. But we have to note that the envelope detection part limits pass band and response speed of AGC system. Expand. An equivalent circuit is derived which is used in the study of dynamic behaviour. The conventional AGC consists of many block circuits, as shown in Fig. In addition, the design complexity of the proposed AGC is reduced Apr 2, 2001 · Automatic Gain Control (AGC) circuits are widely used in numerous applications to automatically adjust the level of an input signal to a desired value. Given an input signal x (n) in Figure 13-76 Introduction. 1. After corroborating its behavior, the Nov 7, 2022 · Analog Devices, “Design and Operation of Automatic Gain Control Loops for Receivers in Modern Communications Systems” Analog Devices, “AD8368 800 MHz, Linear-in-dB VGA with AGC Detector” Analog Devices, CN3090, “20 GHz to 37. Jan 3, 2009 · An automatic gain control (AGC) circuit composed of a variable gain amplifier (VGA), a peak detector (PD), and a non-linear controller (NC) for digital hearing aid is proposed. Abstract This paper presents the design of an automatic gain control (AGC) loop for high-speed communication systems, which can be used in wired, wireless, or optical receiver. For signals whose input dynamic range is around 50 dB, the output signal variation can be reduced to 0. The design follows a bottom-up designing philosophy; then, the first step is to simulate the mathematical behavior of the proposal. 20. However, AGC can also have a slow response time Aug 16, 2011 · Design of an automatic gain control loop for high speed communication. Lyon goes deep into mathematical analysis of the properties of the Automatic Gain Control circuit. Article. The circuit shown in Figure 1 uses the ADL6010 detector, along with the HMC985A voltage variable attenuator (VVA) and the HMC635 RF amplifier, to provide automatic gain control over a wide range of input frequencies (20 GHz to 37. Sep 30, 2009 · Automatic Gain Control or AGC is a circuit design which maintain the same level of amplification for sound or radio frequency. Mar 19, 2020 · Description: The video discusses the following -Concept of AGC in radio receivers-Different types of AGC circuits-Working of delayed AGC circuit This paper demonstrates a real-time automatic gain control (AGC) circuit based on peak detection module for very low frequency (3KHz $\\sim30$ kHz) communications. The first is an “ideal” AGC curve. DOI: 10. The detector shown in the example is a peak detector, but an RMS detector can also be used. AGC process: (a) linear AGC circuit; (b) example input x (n) with amplitude fluctuations; (c) y (n) output for a = 0. The AGC architecture contains two-stage variable gain amplifiers (VGAs) which are implemented with a Gilbert cell, a peak detector (PD), a low pass filter, an operational amplifier, and two voltage to current (V—I) convertors. 1. The AVC circuit works this way: the FET (t1) is used as a variable resistor. g. The dynamic range of the input signal is considered 57 dB. 18-µm CMOS technology. The design is implemented on the EP1S40F1020 FPGA chip. Our system consists of two HMC624 digitally controlled attenuators, two PSA4-5043+ gain blocks, one AD8310 log detector and one STM32F103 microcontroller. Read more. A complex form of automatic gain control (agc) or instantaneous automatic gain control (iagc) is used during normal operation. Fig 1: Automatic gain control is a closed-loop approach for adjusting input-amplifier gain based on input signal strength and a comparison setpoint to continually provide the best match of the amplifier input span with the input Aug 29, 2022 · The International Journal of Circuit Theory and Applications is an electrical engineering journal using circuit theory to solve engineering problems. CIRCUIT FUNCTION AND BENEFITS . The PD shows an input power range of Nov 26, 2006 · A CMOS automatic gain control (AGC) circuit for power line communication application is presented. It uses negative feedback just like op-amp circuits, but the controlled variable is the sine wave amplitude rather than voltage. One stage VGA achieves 30 dB gain due to the use of An up-down counter, multiplier, digital-to-analog (D/A) converter, and high-speed comparators are employed to achieve an automatic gain control (AGC) circuit, which corrects the pair of characteristic roots of the overall system automatically to the imaginary axis of the complex frequency plane. 5 Res. 4V output signal (V OUT) with the given reference value +1. I was thinking of using a PIC microcontroller and an adjustable gain amplifier, but I think This paper presents a fast settling compact feedforward automatic gain control (AGC) suitable for use in wireless communication systems such as WLAN or Bluetooth receivers where the use of traditional closed loop feedback amplifiers forms a boundary due to the stringent settling time constraints. 2mus. Without the transistor and the passive components with no values marked (aka a basic amplifier), when I tune the radio, I sometimes hear it oscillate which gives me the indication that I'm in need of Sep 15, 2017 · With an AVC circuit diagram, devices can adjust the volume level of sound output without needing manual input. I need to build an AGC for a project (LED light organ). The detector output can be tapped, amplified using an Op-Amp May 27, 2022 · This paper presents a low-power and compact automatic gain control circuit which consumes only 1. 01 and R = 1. The role of the AGC is to provide relatively constant You'll get a detailed solution from a subject matter expert that helps you learn core concepts. Mar 25, 2017 · Hello! This is my attempt at designing a very simple AGC circuit. Operating timing of the AGC circuit is controlled by the FPGA board, while voltage selection module is adaptively switched according to the output of the peak detection circuit. 5573/JSTS. Biomed. c Jan 1, 2013 · The paper proposes a new circuit of all-digital automatic gain control (AGC) in the gas ultrasonic flowmeter at first. The second component is a filter, which filters out any noise so that only the Oct 6, 2004 · This work presents an automatic gain control circuit used to control the output power of an off-chip power amplifier. Additionally, it has a digitally controlled feedback. This control ensures that the peak value of V. Consider a system wherein an amplifier that is part of an AGC circuit functions to generate an output signal by amplifying an analog input signal. The VGA has a gain control range of -28~23 dB with a 1GHz 3-dB gain bandwidth using a cascode amplifier with negative capacitance. Oct 26, 2016 · I'm trying to implement a simple automatic gain control to my amplifier circuit. Each of the major components of the AGC circuit is modeled and the criteria to obtain Jan 1, 2012 · This paper presents an automatic gain control (AGC) circuit which is used in a single-chip UHF RFID reader transceiver system. As a result, it eliminates those intensity differences, annoying, and of speech music, which sometimes appear on radio and television. 008 mm 2 fabricated in TSMC 0. 2020. If the signal is too low the AGC circuit will increase (amplify) the level and if is to high will lower it to maintain a constant level as possible. We would like to show you a description here but the site won’t allow us. The gain of the two VGAs can be varied linearly from 0dB to 60dB with respect to a control voltage from 0. Then the adc and AGC circuits in THE AGC system in the WiMAX receiver are introduced and analyzed theoretically. Originally, those circuits were described as automatic volume control circuits, a few years later they were generalized under the name of Automatic Gain Control (AGC) circuits [1,2]. First, there’s an audio gain amplifier, which amplifies or decreases the input signal. Basically I want to measure the peak voltage of an input waveform and adjust the gain of an op-amp or other amplifier to compensate. AGC is a feedback system that adjusts the gain of a variable-gain amplifier to maintain a constant output amplitude in response to changes in input amplitude. if i use its (the digpots) threshold then it would constantly cycle up one and down one and it think this would induce alot of Nov 30, 2008 · Abstract: An automatic gain control (AGC) circuit composed of a variable gain amplifier (VGA), a peak detector (PD), and a non-linear controller (NC) for digital hearing aid is proposed. The AGC circuit is mainly composed of an amplifier, PID controller, sampling circuit and reference circuit. This is achieved by providing more amplification to weak signals and less amplification to strong signals thus maintaining a constant signal Automatic Gain Control is a system for regulating amplitude in the electronic circuit in an amplifier by ensuring the output signal is at a constant level. For this reason, AGC circuits reduce the required input dynamic range of subsequent conditioning circuits for resonant sensors, where information is frequency modulated. Jan 11, 2018 · It is basically a more straightforward way of implementing automatic gain control (AGC), though a limiter is not called an AGC circuit and for good reason—AGC uses feedback to ensure that the output signal always has a certain amplitude, whereas a limiter merely ensures that the output doesn’t exceed a certain amplitude. Supplied at 1. The proposed AGC incorporates a modified sample and hold peak-detector. The circuit retains the manual gain control function, circuits, a few years later they were generalized under the name of Automatic Gain Control (AGC) circuits [1,2]. The Automatic Gain Control principle is widely use in AM receivers and Low frequency automatic gain control (AGC) circuits are used in audio and power equipment for applications such as sensitive microphone preamplifiers (preamps) and regulators. 8 V, it 2 days ago · Yesterday i just searched "automatic gain control" circuit in this web site and i could finally found your schematic. The main objective of this paper is to provide the hypothetical reader with a deep insight of the theory and design of AGC circuits ranging from audio to RF applications. JSTS Journal of Semiconductor Technology and Science 20 (5):447-455. One stage VGA achieves 30 dB gain due to the use of Jan 1, 2011 · Automatic gain control circuit configurations require three key components that are employed in all or most architectures: a variable gain amplifier, a peak signal detector and a gain control voltage generation circuit. This paper presents the design of an automatic gain control (AGC) loop for high‐speed communication systems, which can be used in wired, wireless, or optical receiver, and shows that a gain tuning range of 47 dB (−7 to 40 dB) is obtained in this design. 5 dBm. Audio distortion can damage speakers, and its presence, or significance, can often be reduced by decreasing the gain of the system. Mar 1, 2016 · The generalized design of Automatic Gain Control (AGC) circuits that have constant settling time is described. The input have a 6V offset and the supply voltage is 12V. Mar 1, 2023 · This work presents an inductorless, 10 Gbps automatic gain control (AGC) circuit including a speed enhanced variable gain amplifier (VGA), a power detector, a comparator, and a novel exponential Jul 25, 2010 · 2,595. The AGC has been implemented in a 0. 5 V, the AGC has been operated in the sub-threshold region with Automatic Gain Control. The input signal is amplified by the variable gain amplifier (VGA). We will begin studying the control theory involved behind the simple and primary idea of an AGC system. 93V. What I'm amplifying is a small signal from a superregen receiver. 4V and connect the control voltage to the FET. The linear-in-dB nature of both the VGA and detector produces control dynamics that are constant and linear throughout the control range. c). The loop filter averages the control signal This book analyzes automatic gain control (AGC) loop circuits and demonstrates AGC solutions in the environment of wireless receivers, mainly in wireless receivers with stringent constraints in settling-time and wide dynamic range, such as WLAN and Bluetooth receivers. I have to implement a circuit which is supposed to amplify an input amplitude to constant amplitude 8Vpp output even if the input amplitude is varied (0. Apr 14, 2010 · i need an automatic gain control for an amp. Therefore, the AGC circuits are often implemented partially or completely in the digital domain. The VGA is a fully differential circuit with differential output swing of 1-Vpp. To achieve low power consumption under 0. The repeater employs two stages radio frequency AGC circuits, which are gain control of input part and output part respectively, so that the system can work normally and automatically Definition. However, upon replacing the LT1498 with the MCP602, the circuit no longer controls the gain as expected. The average or peak output signal level is used to adjust the gain to a suitabl Automatic Gain Control (AGC) circuits Theory and design. The ability to set the gain level in a circuit and have it control itself is a very useful function. 1-1GHz automatic gain control (AGC) circuit comprised of a variable gain amplifier (VGA), power detector (PD), and comparator. The ideal AGC has a transfer function as in [ref:fig-agc-transfer-function] . An automatic gain control (AGC) topology with a variable gain amplifier utilizing a titanium dioxide (TiO2) memristor using a linearized feedback loop amplitude model is designed and a design tradeoff analysis based on distortion performance is developed. This approach can help manage the signal delay and frequency response issues by adjusting the circuit's properties in real-time, based on the characteristics of the incoming signal. The resistance between the drain and source of T1 can be between 150Ω and infinite. This post is based on the Chapter 11 of the awesome book “Human and Machine Hearing” by Richard Lyon. An AVC circuit diagram is usually made up of four main components. Feb 1, 2013 · A differential automatic gain control (AGC) circuit is presented. Matlab is the mathematical tool used for mathematical validation. The circuit shown in . Digital AGC. Jun 13, 2008 · In order to communicate successfully for mobile stations in signal dead zone, this paper presents an inverse-gain- feedback dual-loop automatic gain control (AGC) circuit used in WCDMA repeater uplink system. As such automatic gain control plays a crucial role in SDR. Through the MCU to determine whether the Sep 16, 2020 · Automatic gain control (AGC) circuits are used in many systems where the amplitude of the input signal can vary over a wide dynamic range. Despite the amplitude variation of the incoming signals, it adjusts the average output signal, which changes the amplifier’s gain. AGC can help to maintain a constant output level, reduce distortion, and improve the signal-to-noise ratio. D1 is used to provide negative voltage for the and R7 and C1 to change it to DC. building block in many syst ems where the amplitude of the . 5 GHz) and amplitude. I have a pspice program for student. 3 ). This circuit is implemented in an IBM CMOS RF 0. I'm a new one here and I'm just curious about this circuit. With the huge development of communication systems during the second half of the XX century, the need for selectivity and good control of the output signal’s level became a fundamental issue in the design of any communication system. Unfortunately, as Figures 6-14 and 6-19 both show, even weak signals do not escape this reduction. what might be the reason? [posting the images of the schematic, input and Working Principle of Automatic Gain Control is a system by means of which the overall gain of a radio receiver is varied automatically with the changing strength of the received signal, to keep the output substantially constant. A negative feedback technique with digital hardware is applied on the loop gain control. In this work, the AGC can effectively lock the amplitude of the input signal within 0. The work is extended to cover sampled data a. 6. A de bias voltage, derived from the detector as shown and explained in connection with Figure 6-13, is applied to a Apr 10, 2009 · The automatic gain control circuit AGC provides a signal with less harmonics and additional amplification, between certain limits. The characterisation of a negative feedback type of automatic gain control (AGC) circuit that will be an integral part of the heterodyne radiometer system operating at a frequency range of 75-86 GHz at SST-1 tokamak is described. Learn how to design a high gain audio AGC amplifier circuit using a transistor and an op-amp. Automatic gain control (AGC) is a technique found in many electronic devices. Figure 6-19 also shows two other AGC curves. Jun 20, 2010 · An automatic gain control (AGC) topology with a variable gain amplifier (VGA) utilizing a titanium dioxide (TiO 2 ) memristor is described. And I followed a schematic like your one. 5 GHz, RF Automatic Gain Control (AGC) Circuit” Analog Devices, “Chapter VIII: Design and Operation of Automatic Gain Control Loops for Receivers in Modern Communications Systems” Analog Devices, “Stable, Closed-Loop, Automatic Power Control for RF Applications AN-1507” An automatic gain control (AGC) circuit would keep the audio output at a more consistent level on weak signals and attenuate the audio when the incoming signal is at a much higher level, thereby elim-inating the need to readjust gain manually. A The control parameter a regulates the amplitude of the feedback signal and is used to control the AGC's time constant (how rapidly gain changes take effect). Eng. Nonetheless, the Oct 1, 2020 · Firstly, the basic components and main characteristic indexes of the AUTOMATIC gain control system are introduced, and the output formula of AGC model is obtained through the analysis of a step-type AGC. Figure 1 provides closed-loop, automatic power control using a variable gain amplifier (VGA), ADL5330, and a log detector, AD8318. Consider the circuit shown in Figure 6. The HMC624 digital step attenuators have both parallel and Serial programming interfaces setting the attenuation value. In this chapter Dr. This simple AGC circuit meets that need. Since feedforward AGCs present great advantages in this context, as an Jan 17, 2013 · This paper presents a fully analog automatic gain control (AGC) circuit based on PID control for ultrasonic echo compensation. The simplest type of agc adjusts the IF The amplifier (OPA621) placed after the circuit converts the output current i of the multiplier (OPA660) into voltage. Abstract— This paper presents an inductorless 0. For the current manuscript, an automatic gain control circuit is proposed; it is designed in current-mode. The comparator compares the signal extracted from the strength of the output by the peak-detector with a reference voltage to set a control signal in the output. The main objective of this paper is to provide the hypothetical reader with a deep insight of the theory and design of AGC circuits ranging from audio to RF applications and to study the characteristics and performance of the most popular AGC system components. but how can i drive the digital pot. Apr 19, 2012 · An automatic gain control circuit with TiO2 memristor variable gain amplifier. When the input signal level is low, the AGC is disabled and the output is a linear function of the input. xp oe li bb um mo dm nx ob bn