handon_lab1_ece304

# handon_lab1_ece304 - 1 Determine the DC operating point 2...

This preview shows pages 1–2. Sign up to view the full content.

ECE 304 Hands-on Lab #1 The differential amplifier is an important circuit configuration used to amplify the difference between two signals. This is the input circuit of an operational amplifier, and thus underlies much of modern analog electronics. Figure 1 shows an example of a simple differential amplifier using BJTs. The symmetry of this circuit can reject unwanted interference such as temperature effects and common-mode noise. Figure 1. A simple BJT differential amplifier. AC sources are meant to be directly connected to the points marked Vin1 and Vin2. PRELAB Using the circuit of Figure 1, perform hand calculations to estimate the DC operating point of the amplifier and the differential-mode gain. Assume the transistors are equivalent 2N2222s and have a thermal voltage Vt of 25.9 mV.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 1. Determine the DC operating point. 2. Determine the differential-mode gain using the following signals for inputs: o Vin1 = amplitude of 150 mV and frequency of 5 kHz o Vin2 = ground. LABORATORY EXPERIMENTS In the lab, build a differential amplifier using two 2N2222's. Measure the Ib and Ic to obtain beta for each transistor. Then replace one transistor with a different one. Measure the beta values again. For both circuits, take the measurements described above (operating point and differential-mode gain). Compare the circuit results to each other and to the pre-lab results. Which circuit performs better? What is the relationship to beta? Be sure that all relevant spec sheets are included in your lab notebook....
View Full Document

## This note was uploaded on 11/08/2009 for the course ECE 304 taught by Professor Ma during the Spring '08 term at Arizona.

### Page1 / 2

handon_lab1_ece304 - 1 Determine the DC operating point 2...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online