Essays on Amplifier

* Names of Group: 1. .. ID #: 2. ID #: 3 ID #: * Date: / / .

Results:

Based on measurements, complete the table below: Discussion: Discuss the application of common collector transistor circuit. The common collector configuration of the BGJ amplifier is mostly commonly employed as buffer or emitter follower. The voltage gain of the common collector amplifier is nearly unity and provides large current amplification. It is used in applications where current sourcing is required without modifying the voltage. The input resistance is quite high so it draws negligible current from source. Moreover, the load circuit will not interfere ...

* Names of Group: 1. .. ID #: 2. ID #: 3 ID #: * Date: / / .

Discussion:

Using the measurements made in the procedure, calculate the quiescent current IE, and the internal emitter resistance re. The quiescent current IE and internal emitter resistance re can be calculated using the DC analysis carried out in Step#1 and Step#2 of the procedure. The DC voltage measured across RE is used to measure the biasing current across the emitter of BJT. The voltage is measured to be 793mV. Since RE = 1KΩ, so: IE=VERE=0.7931000=0.000793A=0.793mA.

Now, we can calculate the internal resistance of emitter using the formula provided in the procedure. So:

re=0.026IE=0.0260.000793=32.786Ω

Using the values obtained in the experiment; draw the small-signal ac equivalent circuit for the amplifier.

In this part, we will draw the small scale ...

Summary

The given article is about a BiFET GSM-EDGE, which is a power amplifier that consists of a built in circuit to limit current. The collector current is limited to a predetermined level of the value 2.1 Amperes by having a bias circuit incorporated in the power stage of the amplifier thus limiting the HBT cells base current. The power amplifier ruggedness is increased by the given novel scheme in case it is subjected to much mismatch conditions. Furthermore, the matched loads of EDGE and GMSK PAE are maintained in a linear manner. In this paper, current limiting capabilities in ...

Introduction

The Wide-Band Code Division Multiple Access (W-CDMA) is a third generation handset system that achieves high data transmission by utilizing a wider spectrum frequency. Issues that arise in handsets such as a low spectral growth and maintenance of modulation accuracy require a low adjacent channel leakage power ratio (ACLR) especially in the case of the W-CDMA handset systems. High linearization in the portable W-CDMA systems can be improved by increasing the gain compression point that creates the AM-AM distortion. As such this can be achieved by using an on-chip linearizer. A new on-chip active bias circuit can be used ...

Abstract

In this article, a new bias current regulation circuit of a one-stage bipolar and Filed Effect Transistor amp is described. How the FET achieves high precision and simplicity by means of a combination of feedback error amplifier with a bandgap reference is explained.

Introduction

Regulating current through active devices sets the output level in a drive circuit. Figure 1. Below shows typical application of these active devices. Qo I used as a FET rather than a BJT. In a limiting amp, the Qo acts as a switch and the output signal level is proportional to the bias current. The gain ...

PURPOSE

Design an active second order Low-pass filter and characterize its frequency response.EQUIPMENT AND COMPONENTS Oscilloscope Power Supply Function Generator UA741 or LM741 OP AMP 4.7 nF Capacitors

Resistors

PRELAB 1. The RC circuit is shown in the following figure. Node Voltage Analysis is done in order to generate a transfer function Tvs=V2sV1s. In the circuit, voltage at node A is also the input voltage (V1=VA), and voltage at node D is also the output voltage (V2=VD).

KCL at node B:

V1-VBR1=VB-V21/sC1+VB-VCR2 (1)

KCL at node C:

VB-VCR2=VC1/sC2 (2) V2=uVC→VC=V2u (3)

Simplifying (2):

VB=VC1+sR2C2 (4)

Then, substituting (3) to (4):

VB=V2u1+sR2C2 (5)

Substituting (3) and (5) to (1):

V1-V2u1+sR2C2R1=V2u1+sR2C2-V21sC1+V2u1+sR2C2-V2uR2 V1-V2u1+sR2C2R1=V2u1-u+sR2C21sC1+V2usR2C2R2 V1-V2u1+ ...

Aims

Studying the vibrational modes of organ pipes Introduction Sound is a vibration that arises from a mechanical wave of pressure and displacement, through a medium like air or water (Berg and Stock, 23). The reception and perception of these waves by the brain is referred to as sound. On the other hand, acoustics deals with the study of these mechanical waves in matter (pg. 40). In this experiment, the organ pipe is the main target of discussion. This is a sound producing wind instrument that resonates at a specific pitch when pressurized air is driven through it. A complete ...