Op amp open loop gain

Apr 1, 2023 · an op amp, resulting in the noise-gain characteristic for the 1/β curve. In practice, the noise gain and the 1/β curve are the same—until they intercept with the gain-magnitude curve. After that, the noise gain rolls off with the amplifier open-loop response but the 1/β curve continues on its path.

Op amp open loop gain. Real op-amps have an open-loop gain which is a function of frequency, A OL (f), and it declines at high frequencies. In particular, the gain-bandwidth product (GBW) is the frequency at which the op-amp’s open-loop gain drops to 1. Notably, the gain starts declining far before that frequency.

amplifier. Thus the gain of 10 output impedance in Figure 6 is generally 10× higher than the unity-gain results. There is 1/10th the ‘round the loop gain due to the feedback attenuator diminishing loop gain that otherwise would reduce the closed-loop output impedance. The open-loop output impedance is about 30Ω, made obvious by the flat

7.) From the open-loop frequency response, the phase margin can be obtained (F = 1) Measurement: This circuit probably will not work unless the op amp gain is very low. 01 + - v V OS IN v OUT V DD C L R L V SS Op-amp Comparator. The comparator is an electronic decision making circuit that makes use of an operational amplifiers very high gain in its open-loop state, that is, there is no feedback resistor. The Op-amp comparator compares one analogue voltage level with another analogue voltage level, or some preset reference voltage, V REF and produces ... ElectronicsHub - Tech Reviews | Guides & How-to | Latest TrendsGain = R f /R in. For example if the gain is 5, then the output voltage will be 5 times greater than the input voltage. Working of non-Inverting Op-amp Gain Calculator. This non-inverting op-amp gain calculator calculates the gain for non-inverting op-amp according to the below equation, where R in is the input resistor and R f is the feedback ...The open loop gain of the amplifier is given by the following formula: AV = Vout/Vin. where: AV = voltage gain. Vout = output voltage. Vin = input voltage = (V + – V –) In an ideal Op Amp, open loop gain ( operational amplifier the gain) is infinite. Since the op amp is real, its gain is between 20,000 and 200,000 (in 741C operational ...

Ideal OP AMP Model Open-loop gain : µ⇒∝ Input impedance : RI ⇒∝Ω Output impedance : RO ⇒ 0 Ω Two assumptions: 1. No current flowing in and out of the input terminals of the op-amp (high input impedance of op-amp). 2. If the output is not in saturation, the voltage between the inverting and non-inverting input terminals is zero. OP ... That is, the output signal is not feedback in any form as part of the input signal. In open loop configuration, The OPAMP functions as a high gain amplifier.common-mode gain, A D/ACM. For an op amp, the differential gain is simply the open-loop gain A. Then, CMRR = A/ACM and rewriting this shows the common-mode gain to be ACM = A/CMRR. However, by definition ACM = eocm/eicm where eocm is the output signal resulting from eicm. Combining the two ACM equations results in e ocm = Aeicm/CMRR. To support Op-Amp Open Loop Gain. The high open loop gain leads to the voltage rule. Practically, the gain is so high that the output will be driven to. This is useful in the comparator. For practical applications other than the comparator, negative feedback is used to control the device gain. For the main part of the open loop response a typical op-amp acts like an integrator and therefore shifts the phase angle by about 90 degrees. The curve that looks most like 90 degrees is the phase response. Here's the response for an OPA192: - Taken from this blog. And below is a generic op-amp's bode plot: - Taken from here and below an op77: -Sep 25, 2023 · If I chain these two op amps together, I would get \$ Vout = A_{DC gain1}* A_{DC gain2}V_{in} \$ giving me more DC open loop gain. simulate this circuit – Schematic created using CircuitLab. Now for the question: If I do this for two ideal Opamps with DC open loop gain in a closed loop situation I should get more DC open loop gain and be …The gain parameter A is called the open loop gain. The open loop configuration of an op-amp is defined as an op-amp circuit without any circuit loops that connect the output to any of the inputs. inputs. Vp

An operational amplifier (OP Amp) is a direct current coupled voltage amplifier. That is, it increases the input voltage that passes through it. The input resistance of an OP amp should be high whereas the output resistance should be low. An OP amp should also have very high open loop gain. In an ideal OP amp, the input resistance and open loop ...Introduction In this chapter we will discuss the basic operation of the op amp, one of the most common linear design building blocks. In section 1 the basic operation of the op …ElectronicsHub - Tech Reviews | Guides & How-to | Latest TrendsAn operational amplifier (op amp) is an analog circuit block that takes a differential voltage input and produces a single-ended voltage output. There are many different important …

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From the open-loop frequency response, the phase margin can be obtained (F = 1) Measurement: This circuit probably will not work unless the op amp gain is very low. Note that the open-loop gain is the measured maximum gain of the amplifier when no components are present in the feedback loop. Introduction to Ideal Op-Amp ...Look at Open-loop gain in Fig. 4 above, it is graphed for a type 741 op-amp as a function of frequency. At very low frequencies, the open-loop gain of an op-amp is constant, but starts to taper off at about 6Hz or so at a rate of -6dB/octave or -20dB/decade (an octave is a doubling in frequency, and a decade is a ten-fold increase in frequency).Real op-amps have an open-loop gain which is a function of frequency, A OL (f), and it declines at high frequencies. In particular, the gain-bandwidth product (GBW) is the frequency at which the op-amp’s open-loop gain drops to 1. Notably, the gain starts declining far before that frequency.Characteristic of an ideal op-amp – Open Loop gain: Ideally op-amp should have an infinite open-loop gain (practically it is hundreds of thousands of times larger than the potential difference between its input terminals). Input impedance or resistance: Ideally op-amp should have infinite input resistance (practically it should be very high). Output …

Open loop voltage gain; Output offset voltage; Common Mode Rejection Ratio; Slew Rate; This section discusses these characteristics in detail as given below −. Open loop voltage gain. The open loop voltage gain of an op-amp is its differential gain without any feedback path. Mathematically, the open loop voltage gain of an op-amp is ...30 sept 2020 ... Ideally, the open loop gain of an op-amp will be infinite but typical real values range from about 20,000 to 200,000. In most cases, the open ...Because of an internal parasitic capacitance, an op-amp has a first-order delay element (as is the case with a first-order lowpass filter) as shown in Figure 2-8. In the case of typical op-amps, the cut-off frequency of open-loop gain response is between 10 Hz and 100 Hz. The phase of the output lags 45 degrees behind in this frequency range.OPEN-LOOP GAIN Unlike the ideal op amp, a practical op amp has a finite gain. The open-loop dc gain (usually referred to as AVOL) is the gain of the amplifier without the feedback loop being closed, hence the name “open-loop.” For a precision op amp this gain can be vary high, on the order of 160 dB (100 million) or more.The op-amp differential amplifier features low output resistance, high input resistance, and high open loop gain. In an inverting amplifier configuration, the op-amp circuit output gain is negative. All simple mathematical operations such as addition, subtraction, comparison, etc. are possible with op-amp application circuits.12 abr 2023 ... Concept: Unity gain frequency of the op-amp = Open-loop upper cut off frequency × Open-loop gain Calculation: Open-loop gain = 20000 Open ...Open-loop gain. Open-loop gain: The open-loop gain (“A” in Figure 1) of an operational amplifier is the measure of the gain achieved when there is no feedback implemented in the circuit. This means the feedback path, or loop, is open. An open-loop gain often must be exceedingly large (10,000+) to be useful in itself, except with voltage ...25 oct 2020 ... So, the open loop gain of the op amp is, 2 × 105. whereas closed loop gain comes to only 2. Ezoic. Let us take another example of closed loop ...Ideal Op Amp Op-Amp with dc bias • Infinite input impedance – No current goes in • Zero output impedance • Infinite open-loop gain, A – How is this possible? – Use feedback to define circuit gain • Infinite bandwidth • Infinite common-mode rejectionAbstract: Simulating the open loop gain of an amplifier circuit is a highly misunderstood subject in Electrical and Electronics Engineering. In order to address that issue we describe four methods that we use to successfully simulate an operational amplifier open loop gain in an engineering education environment.Real op-amps have an open-loop gain which is a function of frequency, A OL (f), and it declines at high frequencies. In particular, the gain-bandwidth product (GBW) is the frequency at which the op-amp’s open-loop gain drops to 1. Notably, the gain starts declining far before that frequency.

Apr 8, 2021 · The open loop gain of an operational amplifier or op amp is the output voltage divided by the difference between the noninverting and inverting inputs of the amplifier as shown in equation 1. The typical gain of an op amp ranges from 10 4 to 10 5 or higher. Because the gain is so high, the input signal for an op amp must be very small to keep ...

An operational amplifier (op amp) is an analog circuit block that takes a differential voltage input and produces a single-ended voltage output. There are many different important characteristics and parameters related to op amps. Open-loop gain: The open-loop gain (“A” in Figure 1) of an operational amplifier is the measure of the gain achieved when there is …Typically an op-amp may have a maximal open-loop gain of around , or 100 dB. An op-amp with a large open-loop gain offers high precision when used as an inverting amplifier . Normally, negative feedback is applied around an amplifier with high open-loop gain, to reduce the gain of the complete circuit to a desired value. DefinitionNov 17, 2014 · Figure 2 depicts a unity-gain buffer driving a capacitive load. Equation (1) shows the transfer function for the circuit in Figure 2. Not depicted in Figure 2 is the open-loop output impedance of the op amp, R o. + + C load – V in V out +V s R iso-V s Figure 2: Unity-Gain Buffer with R iso Stability Compensation s 1 R R C s 1 C R T s o iso ...Because of an internal parasitic capacitance, an op-amp has a first-order delay element (as is the case with a first-order lowpass filter) as shown in Figure 2-8. In the case of typical op-amps, the cut-off frequency of open-loop gain response is between 10 Hz and 100 Hz. The phase of the output lags 45 degrees behind in this frequency range.Aug 6, 2011 · an example, an op amp with an open-loop gain of 106 dB can be written in terms of V/V as OL_DCdB A 106 dB 20 20 OUT OL_DCV/V ERR V V A 10 10 199,526 . V V = = = =(7) Figure 2 shows the simplified open-loop gain of the OPA211 along with the closed-loop gain in a non-inverting Table 1. Excerpt from TI OPA211/2211 data sheetan op amp, resulting in the noise-gain characteristic for the 1/β curve. In practice, the noise gain and the 1/β curve are the same—until they intercept with the gain-magnitude curve. After that, the noise gain rolls off with the amplifier open-loop response but the 1/β curve continues on its path.Gorilla Tag is an exhilarating virtual reality game that allows players to swing through the jungle as a nimble gorilla. With its immersive gameplay and competitive nature, it’s no wonder that players are constantly on the lookout for ways ...An operational amplifier (often op amp or opamp) is a DC-coupled high- gain electronic voltage amplifier with a differential input and, usually, a single-ended output. [1] In this configuration, an op amp produces an output potential (relative to circuit ground) that is typically 100,000 times larger than the potential difference between its ...

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an op amp, resulting in the noise-gain characteristic for the 1/β curve. In practice, the noise gain and the 1/β curve are the same—until they intercept with the gain-magnitude curve. After that, the noise gain rolls off with the amplifier open-loop response but the 1/β curve continues on its path. The key op amp specifications for a voltage feedback op amp in this application are the gain bandwidth product (GBP) and the phase margin (PM). Figure 1 shows the open-loop gain and phase vs. frequency for the ADA4610, a popular precision op amp. The plot shows that the op amp gain at low frequency is greater than 30,000 (90 dB), rolling off at ...Now, when we talk specifically about an operational amplifier, the symbol for that, we use for an operational amplifier, is a triangle. It has two inputs, one is the plus input, one is the minus input, and it has an output, and it also has two power supplies to it. There's some sort of plus voltage that goes into it, and some sort of minus voltage.The Gain Bandwidth Product (GBWP) of an amplifier is the product of the amplifier open-loop gain times the frequency at any point in the frequency range where the amplifier's response is attenuating at a rate of -20 dB per decade of frequency. And GBWP keeps constant where the slope is -20 dB/decade.Assume the op amp is ideal, with infinite open-loop gain, A. The output voltage hits the positive voltage supply rail, V CC volts, whenever the differential input voltage is positive, i.e., when V + >V – . Likewise, the output voltage sits at the ground rail, 0 volts, whenever the differential input voltage is negative, i.e., when V + <V – . Sep 24, 2013 · infinite open loop gain the inverting input of the op-amp is a virtual ground, a circuit node that will stay at ground as long as the circuit is working, even though it is not directly connected to ground. Since the op-amp inputs draw no current, it follows that and the dc closed loop gain is This is the “Golden Rule” result.Oct 19, 2023 · A regular op amp features high open-loop gain between the differential input and the one output; a fully differential op amp features high open-loop gain between the differential input and the differential output. Feedback should also be applied differentially. Figure 1 shows four external resistors feeding a portion of the differential output ...Open loop-op-amp Configuration: The term open-loop indicates that no feedback in any form is fed to the input from the output. When connected in open – loop, the op-amp functions as a very high gain amplifier. There are three open – loop configurations of op-amp namely. 1. differential amplifier. 2.Jun 17, 2015 · This means you can assume current does not flow into the two op-amp inputs and these can be regarded as high impedances. Additionally, you can assume the op-amp open-loop gain is very high and the impact of this is that for an output voltage that is reasonable (i.e. somewhere within the bounds of the power supply rails), the difference …Aug 6, 2011 · an example, an op amp with an open-loop gain of 106 dB can be written in terms of V/V as OL_DCdB A 106 dB 20 20 OUT OL_DCV/V ERR V V A 10 10 199,526 . V V = = = =(7) Figure 2 shows the simplified open-loop gain of the OPA211 along with the closed-loop gain in a non-inverting Table 1. Excerpt from TI OPA211/2211 data sheet ….

the open-loop voltage gain of a CFA depends on the value of the feedback network. Removing R E, the feedback network term, from the equation for open-loop voltage gain yields a more general expression that describes the amplifier’s open-loop performance in terms of its intrinsic characteristics. This equation would May 22, 2022 · The quantity a in this equation is the open-loop gain or open-loop transfer function of the amplifier. (Note that a gain of a is assumed, even if it is not explicitly indicated inside the amplifier symbol.) The dynamics normally associated with this transfer function are frequently emphasized by writ­ing \(a(s)\). Jan 15, 2021 · A common configuration is just using the op amp open loop—without feedback—and letting its high gain produce comparator operation. Without negative feedback, the two inputs will not necessarily remain at the same voltage, so the fourth ideal op amp assumption is not valid. Figure 1 shows an op amp configuredInvestorPlace - Stock Market News, Stock Advice & Trading Tips Before jumping directly into momentum stocks worth buying now, it’s impor... InvestorPlace - Stock Market News, Stock Advice & Trading Tips Before jumping directly int...Nov 16, 2011 · DC open loop gain . A OL is the ratio of the output voltage to the differential input voltage. The measurement involves measuring the input offset voltage at several points and calculating A OL. The procedure for measuring A OL requires some knowledge of the DUT op amp’s output behavior. Ideally, an op amp could swing all the way to both ... 7.) From the open-loop frequency response, the phase margin can be obtained (F = 1) Measurement: This circuit probably will not work unless the op amp gain is very low. 01 + - v V OS IN v OUT V DD C L R L V SS The Gain Bandwidth Product (GBWP) of an amplifier is the product of the amplifier open-loop gain times the frequency at any point in the frequency range where the amplifier's response is attenuating at a rate of -20 dB per decade of frequency. And GBWP keeps constant where the slope is -20 dB/decade.Oct 13, 2012 · Inside the simplified op amp model, the open-loop gain is set by the gain of EGAIN. Initially, set EGAIN to 100k. The ideal output at V(5) is generated a simple voltage controlled source EAMP1 set to an exact gain of 10.0. CIRCUIT INSIGHT Run a Transient Simulation and plot the output V(3). Place a cursor on the trace to get a precise reading ...The former is referred to as the “closed-loop gain” since it includes the feedback, whereas the latter is termed the “ open-loop gain ” since it is the gain of the op amp without a feedback loop. The gain produced by the feedback network is, theoretically, 1/ β, Equation 15.5. The real transfer function gain is either this value or the ... Op amp open loop gain, An operational amplifier (op amp) is an analog circuit block that takes a differential voltage input and produces a single-ended voltage output. There are many different important characteristics and parameters related to op amps. Open-loop gain: The open-loop gain ("A" in Figure 1) of an operational amplifier is the measure of the gain achieved when there is no feedback, Aug 5, 2020 · Ro – Output Resistance of the op-amp. A- Open loop gain of the op-amp. Characteristics of Ideal Op-Amp: As, mentioned above, the op-amp is a very versatile IC and can be used in various applications. Because of its favorable characteristics, it is used in various applications. Here is the list of characteristics of the ideal op-amp , To plot the open-loop gain of an op-amp using SPICE, you must properly bias its inputs so that its output does not rail up or down. Considering the large open …, 22 may 2022 ... The quantity a in this equation is the open-loop gain or open-loop transfer function of the amplifier. (Note that a gain of a is assumed, even ..., 17 mar 2022 ... The theoretical open-loop gain of a perfect amplifier is infinite ... Example gain spectrum for an op-amp showing the unity-gain bandwidth., Operational Amplifier General Conditions. • The Operational Amplifier, or Op-amp as it is most commonly called, can be an ideal amplifier with infinite Gain and Bandwidth when used in the Open-loop mode with typical DC gains of well over 100,000 or 100dB. • The basic Op-amp construction is of a 3-terminal device, with 2-inputs and 1-output ..., This is the open-loop frequency & phase response for a typical general-purpose op-amp extracted from the data sheet. The gain (blue curve) is above 110dB for very low frequencies but rolls off at 2Hz by -20dB per decade until it reaches 0dB at around 1MHz. This behavior is due to the op-amp compensation which ensures it is stable …, 5.3: Gain-Bandwidth Product. The open loop frequency response of a general-purpose op amp is shown in Figure 5.3.1a. Although the exact frequency and gain values will differ from model to model, all devices will exhibit this same general shape and 20 dB per decade rolloff slope., So the closed loop gain is 1 /(-0.002001), which is about -500. In an ideal op-amp, the gain for this inverting configuration would be Gideal = -R2/R1 = -100k/100 = …, This op-amp was implemented in the 180 nm CMOS technology and achieved 86.96 MHz unity-gain frequency, 51.7° phase margin at 32 pF load capacitor and 99.83 dB DC gain, that is, a 36.21 dB improvement over a two-stage op-amp with the same power consumption. The op-amp consumed 7.74 mW with a supply voltage of 1.8 V., From a measurement perspective, CMRR is defined as the ratio of an op amp’s open-loop differential gain to its open-loop common-mode gain. In the real world, these two gain characteristics can be tricky to isolate from one another, but the power of simulation allows you to do this effectively. Figure 4 shows the recommended test circuit., The operational amplifier (op-amp) is a voltage controlled voltage source with very high gain. It is a five terminal four port active element. The symbol of the op-amp with the …, Nov 11, 2015 · However, keep in mind that the unity-gain frequency of an amplifier is not always the same as the GBP: the GBP is determined by the low-frequency open-loop gain and the open-loop cutoff frequency, whereas the unity-gain frequency is the frequency at which the open-loop gain equals 1. If the amplifier has a second (non-dominant) pole that ..., The former is referred to as the “closed-loop gain” since it includes the feedback, whereas the latter is termed the “ open-loop gain ” since it is the gain of the op amp without a feedback loop. The gain produced by the feedback network is, theoretically, 1/ β, Equation 15.5. The real transfer function gain is either this value or the ..., Aug 6, 2011 · of the op amp. If the op amp has a closed-loop gain of 100, the cutoff frequency is 800 kHz (80 MHz/100). Amplifiers: Op Amps By Miroslav Oljaca, Senior Applications Engineer, and Henry Surtihadi, Analog Design Engineer 140 120 100 80 60 40 20 0 –20 10 100 1 k 10 k 100 k 1 M 10 M 100 M Frequency (Hz) Gain (dB) f 0 A OL_DC …, Characteristic of an ideal op-amp – Open Loop gain: Ideally op-amp should have an infinite open-loop gain (practically it is hundreds of thousands of times larger than the potential difference between its input terminals). Input impedance or resistance: Ideally op-amp should have infinite input resistance (practically it should be very high). Output …, Typically an op-amp may have a maximal open-loop gain of around , or 100 dB. An op-amp with a large open-loop gain offers high precision when used as an inverting amplifier . Normally, negative feedback is applied around an amplifier with high open-loop gain, to reduce the gain of the complete circuit to a desired value. Definition, The auxiliary operational amplifier is used as an integrator to form a stable loop with extremely high DC open loop gain. 4.3 Open Loop Gain (AOL) Table 2 shows open loop gain characteristics simulation results for the circuit in Fig. 8, where a square wave of 1Vp-p and 1Hz is provided to the negative terminal side of the operational amplifier ..., A typical open-loop-gain curve for the TLV278x family of op amps is used as a teaching example and is shown in Figure 2. The op amp’s open-loop gain and phase (a in Equation 1) are represented in Figure 2 by the left and right vertical axes, respectively. Never assume that the op amp open-loop-gain curve is identical to the loop gain because ..., Feb 5, 2019 · In this lab, we will measure the parameters of an actual 741 op amp. The measurement of these parameters will provide insight into the limitations of real world op-amps in various circuit applications. Summary of Procedures Using a 741 op amp, measure the following parameters: (i) DC open loop gain (ii) Input offset voltage, I'm trying to extract two characteristics: "Input Offset Voltage" and "Open Loop Gain" of an opamp LM741 by using LTspice. To do that, I use the following circuit model and plots where the horizontal variable is the input voltage Vin between -2mV to +2mV:, Assume the op amp is ideal, with infinite open-loop gain, A. The output voltage hits the positive voltage supply rail, V CC volts, whenever the differential input voltage is positive, i.e., when V + >V – . Likewise, the output voltage sits at the ground rail, 0 volts, whenever the differential input voltage is negative, i.e., when V + <V – . , The open loop gain of an operational amplifier or op amp is the output voltage divided by the difference between the noninverting and inverting inputs of the amplifier as shown in equation 1. The typical gain of an op amp ranges from 10 4 to 10 5 or higher. Because the gain is so high, the input signal for an op amp must be very small to keep ..., The formula you quote is not the gain of an opamp. It is the gain of a circuit containing an opamp and several resistors. That formula only holds when the open loop gain of the opamp is much larger than that given by the formula. When that is the case, the actual value of the opamp open loop gain drops out of the equation., Op Amp Open-Loop Gain and Open- Loop Gain Nonlinearity Analog Devices, Inc. IN THIS MINI TUTORIAL This mini tutorial explores open-loop gain and open-loop gain nonlinearity when used for voltage feedback op amps, including methods for calculating and understanding these gain relationships. INTRODUCTION Open-Loop Gain, an example, an op amp with an open-loop gain of 106 dB can be written in terms of V/V as OL_DCdB A 106 dB 20 20 OUT OL_DCV/V ERR V V A 10 10 199,526 . V V = = = =(7) , The open-loop gain of an op-amp is very high. Hence, an open loop operational amplifier amplifies a small applied differential input voltage to a huge value. Also, it is true that if we apply small differential input voltage, the operational amplifier amplifies it to a considerable value but this significant value at the output cannot go …, Given that the open-loop gain A is a function of frequency and exhibits a Low-Pass Filter Response, it can be modeled as: where A0 is the DC gain and fb is the cutoff or breakpoint frequency of the open-loop response. Making this change in the control system yields: Substituting the open-loop response into the closed-loop equation gives: A A A v v, The open-loop gain (G V) of an op-amp has the same frequency characteristics as a first-order RC lowpass filter as shown in Figure 2-3.At frequencies higher than the corner frequency (f C) at which the open-loop gain is 3 dB lower than the DC gain, the open-loop gain decreases at a rate of 6 dB per octave (20 dB per decade).In this frequency range, the decibel open-loop gain of the op-amp (G V ..., 15 mar 2017 ... So I have an op-amp with a gain of 110dB according to the data sheet. How do I convert this into V/V? For reference I am looking at this ..., Practical Op-Amps zLinear Imperfections: – Finite open-loop gain (A 0 < ∞ ) – Finite input resistance (R i < ∞ ) – Non-zero output resistance (R o > 0 ) – Finite bandwidth / Gain-BW Trade-Off zOther (non-linear) imperfections: – Slew rate limitations – Finite swing – Offset voltage – Input bias and offset currents – Noise ..., From the open-loop frequency response, the phase margin can be obtained (F = 1) Measurement: This circuit probably will not work unless the op amp gain is very low., The key op amp specifications for a voltage feedback op amp in this application are the gain bandwidth product (GBP) and the phase margin (PM). Figure 1 shows the open-loop gain and phase vs. frequency for the ADA4610, a popular precision op amp. The plot shows that the op amp gain at low frequency is greater than 30,000 (90 dB), rolling off at ...