Regulated Gain Boosted Cascode 3. Moreover, good channel control and high on current requires a thin gate dielectric. At some point, the gain of the auxiliary amplifiers is reduced to the point where the circuit does not settle to the desired accuracy. In Chapter 4, a telescopic cascode amplifier with gain boosting is designed using the gain boosted cascode configuration. Stability Pole-Zero Analysis 3. The operating principle is as follows:

Cascode sources were chosen because it was necessary to keep the bias currents in the top half of the telescopic amplifier as constant as possible to ensure accurate settling. However, conventional device structures such as bulk MOS transistors are approaching fundamental physical limits. A gain-boosting technique was introduced to remedy this problem. Based on gain variation the usablity range is limited to 1. This value is typically very high.

However, conventional device structures such as bulk MOS transistors are approaching fundamental physical limits. A high-gain dc amplifier that has extremely high voltage gain.

This will flow through r02 in addition to the externally applied i x. First step is to design the normal telescopic cascode and the second thsis is to insert the gain boosting amplifiers to obtain the desired gain from the configuration without affecting the bandwidth to a large extent.

operational transconductance amplifier thesis

Different op-amp configurations 2. To control theamplifier’s transconductence we use additional input for a current.

Based on gain variation the usablity range is limited to 1. A fully differential telescopic cascode with gain boosting architecture Essentially transistors M3 and M5 are acting as simple common-source NMOS amplifiers with cascode current loads. This is the least complex OTA, and hence its speed can be very high. I am especially grateful to him for giving me the opportunity to work on such an exciting project. Hence various new circuit pperational have been implemented to solve this problem.


It allows increasing the DC gain of the operational amplifier op amp without sacrificing the output swing of a regular cascode structure.

operational transconductance amplifier thesis

This thesis describes a regulated cascode circuit RGC which provides a high output resistance which, in turn, leads to high gain as compared transcoonductance a normal cascode circuit optimally biased cascode — OBC. The operating principle is as follows: The increased complexity will reduce the speed in comparison to a single stage amplifier.

A gain-boosting technique was introduced to remedy this problem. Since the gain of the circuit is directly related to the output resistance the gain also increases by the same factor.

The gain had increased, amplifler both the unity gain frequency as well as the phase margin was degraded too much.

A 90 dB, 85 MHz operational transconductance amplifier (OTA

This circuit is described later in the chapter. This is an average value for the specified range.

operational transconductance amplifier thesis

Regions of operation of traneconductance transistors T 1 and T, as the output voltage is decreased starting from the maximum possible value. The other advantage of this configuration is that the feedback loop increases the stability of the circuit even when the transistor T2 is in ohmic region, thereby increasing the usable range of the circuit.

Enter the email address you signed up with and we’ll email you a reset link. The input currents are mirrored with a cascoded configuration to produce the output currents.


Later in the chapter a brief description of various operational amplifier parameters that determine the quality and usefulness of the amplifiers is also provided as a guide. Various architectures have been reported to obtain high gain from the circuits.

A 90 dB, 85 MHz operational transconductance amplifier (OTA

A brief summary of results from this review is also presented which leads to the motivation for this particular work. Due to shrinking of power supplies the dynamic range of the overall circuit is also reduced, due to which the 1 signal handling capability of the circuit is also limited. To start with, I would like to thank my parents and trajsconductance brother opeerational for their continued patience, love and confidence in me. Another advantage of the telescopic architecture is that it uses half the bias current of a folded-cascode design because it has two fewer branches for current.

Various techniques have been reported to improve the transconducgance and bandwidth of this configuration [9]. The gate direction is at right angles to the vertical fin.

Proficient presentation for lean and light shape factors: Remember me on this computer. Add this document to collection s. The output of these auxiliary 53 amplifiers is providing an output voltage to bias the gates of M2 and M1.