BJT Differential Amplifier in Electronic Laboratory - Experiment 1 | EE 371, Lab Reports of Microelectronic Circuits

Download BJT Differential Amplifier in Electronic Laboratory - Experiment 1 | EE 371 and more Lab Reports Microelectronic Circuits in PDF only on Docsity! University of Portland School of Engineering EE371 Electronics Laboratory Lab #1 BJT Differential Amplifier Assigned: Mon, Jan 19, 2009 Checkoff Due: Week of Feb 9, 2009 Final Report Due: Mon, Feb 16, 2009 I. Introduction: For this lab assignment, consider the following BJT Differential Amplifier circuit in Fig 1. vB1 Q1 Q2 VCC=+15V vC1 vC2 RC1=18k VEE=−15V RC2=18k vB2 Q3Q4 RB=62k RL1 RL2 Io vE Fig. 1. II. Pre-Lab Exercises: 1) Hand DC Analysis. Assume RL1=RL2=∞ (i.e., opens), VB1=VB2=Ground, β=100, VA=100V, VBE-on=0.7V. Record all results in attached Summary Table. a) Calculate Io b) Calculate VE c) Calculate VC1 d) Calculate VC2 e) Calculate total DC Power, PDC 2) Hand Midband AC Analysis in Differential-Output Mode (DOM). Assume: vout=vc1-vc2, RL1=4.7kΩ, RL2=∞, β=100, VA=100V, VBE-on=0.7V. Record all results in attached Summary Table. a) Calculate Ad b) Calculate Rid c) Calculate Rod d) Calculate Acm e) Calculate Ricm f) Calculate Rocm g) Calculate CMRR 3) Hand Midband AC Analysis in Single-Ended-Output Mode (SEOM). Assume: vout=vc2, RL1=∞, RL2=470kΩ, β=100, VA=100V. Record all results in attached Summary Table. a) Calculate Ad b) Calculate Rid c) Calculate Rod d) Calculate Acm e) Calculate Ricm f) Calculate Rocm g) Calculate CMRR 4) Re-do all above calculations in PSPICE (except for the Rod’s and Rocm’s since PSPICE includes RL in these calculations) using Transfer Function Analysis with Bias Point Details on (similar to how you did your Homework #1). Look at your xxx.out file for the answers. Record all results in attached Summary Table. For PSPICE, set VAF=100, BF=100. III. Laboratory Experimentation 1) Measure and record all your resistor values before building your circuit. 2) Using your Lab Kit and components, build the BJT Differential Amplifier circuit in Fig. 1. Use an LM3046 Transistor Array component for the four matched NPN transistors. Match-up LM3046’s Q1-Q4 just as they are called out in Fig. 1. (An LM3046 device spec is attached for your reference). IMPORTANT: Make sure Pin #13 is connected to VEE=−15V or else you’ll fry the LM3046 chip. 3) DC Analysis: Ground both VB1 and VB2. Set RL1=RL2=∞ (i.e., opens) Measure all DC node voltages and branch currents as listed in Pre-Lab Exercise 1 above. (Note: when measuring branch currents, please do not use the DC Current option on your DMM due to its inherent unreliability. Instead, always measure the DC voltage across the series resistor using your DMM and then use Ohm’s Law to get the current). Record all your results in the attached Summary Table. 4) Midband AC Analysis in Differential-Output Mode (DOM): Set RL1=4.7kΩ and RL2=∞. (Note, vout=vC1−vC2. Measure vout differentially on the oscilloscope and use the Math mode). Rin and Rout Measurements 1) Rin Measurement: v1 or v2100Ω 1kΩ ~vs 47Ω 50Ω(internal) R’ Rin + − a) Select R′≈Rin (expected). b) With the input source circuit (including R′) connected to Rin (i.e. vB1) as shown above, set vs such that v2=vin=vB1≈50mV p-p and approximately 10kHz. Then, precisely measure v2 and record. c) Without disturbing the vs setting, disconnect the entire input source circuit (including R′) from Rin and then precisely measure the resulting open-circuit voltage of the input source circuit, v1, and record. d) Calculate Rin as follows: R R v v vin 2 1 2 = ′ − 2) Rout Measurement: vs v1 or v2100Ω 1kΩ ~ 47Ω 50Ω(internal) R’Rin + − vin + − + − Avovin Rout a) Select R′≈Rout (expected). b) With RL1 (or RL2) removed, connect R′ across the output. Set vs such that v2=vout≈0.5V p-p with an approximate frequency of 10kHz. Then precisely measure v2=vout and record. c) Without disturbing the vs setting, disconnect R′ and precisely measure the resulting open-circuit output voltage, v1=vout, and record. d) Calculate Rout as follows: R R v v vout 1 2 2 = ′ − Summary Table Parameter Hand Part II: 1), 2) and 3) PSPICE Part II: 4) Lab Part III: 3), 4) and 5) DC: I0 VE VC1 VC2 PDC AC (DOM): Ad Rid Rod N/A Acm N/A Ricm N/A Rocm N/A N/A CMRR N/A AC (SEOM): Ad Rid N/A Rod N/A Acm Ricm N/A Rocm N/A N/A CMRR