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What is the relation between bandwidth and gain?
Gain and bandwidth in an amplifier are inversely proportional to each other and their relationship is summarized as the unity-gain bandwidth. Unity-gain bandwidth defines the frequency at which the gain of an amplifier is equal to 1.
Does the open-loop gain increase or decrease with frequency above the critical frequency?
Gain-Bandwidth Product The open-loop gain falls at 6 dB/octave. This means that if we double the frequency, the gain falls to half of what it was. Conversely, if the frequency is halved, the open-loop gain will double, as shown in Figure 1-8.
What is the difference between gain and closed loop bandwidth?
The gain-bandwidth product can be used to calculate the closed-loop gain bandwidth. For example, if the gain-bandwidth product is 1 MHz and the closed-loop gain is 10, then the closed-loop bandwidth is 100 kHz (1 MHz/10 = 100 kHz) GBW/closed-loop gain = closed-loop bandwidth.
What is the bandwidth of a closed loop resistor?
If closed loop components were present, the gain would be reduced to (say) 20dB (blue line) but the bandwidth would increase to 1MHz. The above example is for simple resistors “closing” the loop with negative feedback and the resulting bandwidth (3dB point) is always greater.
What’s the difference between gain bandwidth and bandwidth?
Gain-bandwidth product is defined as the open-loop gain multiplied by the bandwidth. The gain-bandwidth product can be used to calculate the closed-loop gain bandwidth. For example, if the gain-bandwidth product is 1 MHz and the closed-loop gain is 10, then the closed-loop bandwidth is 100 kHz (1 MHz/10 = 100 kHz)
What is the gain of a DC AMP?
This gain is flat from dc to what is referred to as the dominant pole corner frequency. From there the gain falls off at 6 dB/octave (20 dB/decade). An octave is a doubling in frequency and a decade is ×10 in frequency).