Wiki

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revision Previous revision
Next revision
Previous revision
university:courses:electronics:electronics-lab-4 [12 Jul 2019 12:46]
andreeapop Link for the stairstep.csv file needed for BJT curve tracer
university:courses:electronics:electronics-lab-4 [23 Aug 2019 12:39]
amiclaus
Line 1: Line 1:
-====== Activity ​4. A BJT Curve Tracer ======+====== ActivityA BJT Curve Tracer ======
  
 ===== Objective: ===== ===== Objective: =====
Line 28: Line 28:
  
 Build the simple curve tracer circuit shown in Figure 1. The green boxes indicate where to connect the ADALM2000. Using the Scopy Signal Generator tool, in Channel 2  Buffer tab import the csv file for the stairstep signal needed. Build the simple curve tracer circuit shown in Figure 1. The green boxes indicate where to connect the ADALM2000. Using the Scopy Signal Generator tool, in Channel 2  Buffer tab import the csv file for the stairstep signal needed.
-Now at this point set the amplitude to 2 V and the offset to 2.6 V. The waveform in the display should start at 0.6V and increase in 1 V increments to 4.6 V (0.6, 1.6, 2.6, 3.6, 4.6). For each step to be 5 mSec long for a total of 25 mSec, set the sampling rate 200 Hz. +Now at this point set the amplitude to 2 V peak-to-peak ​and the offset to 2.6 V. The waveform in the display should start at 0.6V and increase in 1 V increments to 4.6 V (0.6, 1.6, 2.6, 3.6, 4.6). For each step to be 5 mSec long for a total of 25 mSec, set the sampling rate 200 Hz. 
-In Signal Generator Channel 1 configure a triangle wave with an amplitude of 5V and an offset of 2.5V (wave should swing from 0 to 5V). Set the frequency to 200 Hz ( 5 times the 40 Hz of channel 2). Comparing the waveforms in Channel 1 and Channel 2, the triangle wave in Channel 1 should go through one cycle from 0 to 5 V and back to zero during the time of one step in the waveform in Channel 2. It will probably be necessary to set the phase of Channel 1 to 90 degrees to make them line up in this way. +In Signal Generator Channel 1 configure a triangle wave with an amplitude of 5V peak-to-peak ​and an offset of 2.5V (wave should swing from 0 to 5V). Set the frequency to 200 Hz ( 5 times the 40 Hz of channel 2). Comparing the waveforms in Channel 1 and Channel 2, the triangle wave in Channel 1 should go through one cycle from 0 to 5 V and back to zero during the time of one step in the waveform in Channel 2. It will probably be necessary to set the phase of Channel 1 to 90 degrees to make them line up in this way. 
  
  
Line 153: Line 153:
 <WRAP centeralign>​ Figure 15, Circuit to measure V<​sub>​BE</​sub>​ breadboard connection </​WRAP>​ <WRAP centeralign>​ Figure 15, Circuit to measure V<​sub>​BE</​sub>​ breadboard connection </​WRAP>​
  
-The generator output W1 should be configured for a 100 Hz triangle wave with 2 volt amplitude and -2 volt offset (for an NPN device). The single ended input of scope channel 2+ is used to measure the voltage at the base of the transistor (optionally connect 2- to the emitter to remove any input offset of the op-amp). The setup should be configured with channel 1 connected to display the output of W1 and channel 2 connected to display the base voltage. The emitter current is calculated as the voltage of W1 / 1KΩ.+The generator output W1 should be configured for a 100 Hz triangle wave with 2 volt amplitude ​peak-to-peak ​and -2 volt offset (for an NPN device). The single ended input of scope channel 2+ is used to measure the voltage at the base of the transistor (optionally connect 2- to the emitter to remove any input offset of the op-amp). The setup should be configured with channel 1 connected to display the output of W1 and channel 2 connected to display the base voltage. The emitter current is calculated as the voltage of W1 / 1KΩ.
  
 ===== Procedure: ===== ===== Procedure: =====
university/courses/electronics/electronics-lab-4.txt · Last modified: 23 Aug 2019 12:39 by amiclaus