{"id":39942,"date":"2022-09-07T15:36:52","date_gmt":"2022-09-07T08:36:52","guid":{"rendered":"https:\/\/techmaster.com.vn\/?p=39942"},"modified":"2022-09-16T13:46:45","modified_gmt":"2022-09-16T06:46:45","slug":"oscilloscope-calibration","status":"publish","type":"post","link":"https:\/\/techmaster.com.vn\/en\/oscilloscope-calibration\/","title":{"rendered":"Oscilloscope Calibration"},"content":{"rendered":"

\"Oscilloscope<\/a><\/span><\/p>\n

1. What’s oscilloscope ?<\/strong><\/span><\/h2>\n

Oscilloscope is a device capable to catch\u00a0graph electronic\u00a0signals to analyze and find extraordinary\u00a0signals. This device possesses the characteristic ability to\u00a0plot the\u00a0three main shaft signal\u00a0X, Y, Z. In there, X axis (time), Y axis (voltage), Z axis (brightness intensity). Oscilloscope is capable of recognizing many different signals types such as square, sawtooth, sinusoidal pulses, or even difficult signals such as video and audio. <\/span>Oscilloscopes frequency range from 1Hz to several MHz. Some high-end models can display a frequency signal up to several hundred GHz.<\/span><\/p>\n

\"M\u00e1y<\/a><\/span><\/p>\n

2. <\/strong>Oscilloscope classification<\/strong><\/span><\/h2>\n

Oscilloscopes are classified into two main types: analog oscilloscope and digital oscilloscopes.<\/span><\/p>\n

+ Analog oscilloscope:<\/strong> This is an old\u00a0technology\u00a0oscilloscope, so the measurement frequency is quite low.<\/span><\/p>\n

\"M\u00e1y<\/a><\/span><\/p>\n

+ Digital oscilloscope:\u00a0<\/strong>The new type has a much higher measurement\u00a0frequency than\u00a0analog oscilloscope. With many functions included, it brings convenience during work.<\/span><\/p>\n

\"M\u00e1y<\/a><\/span><\/p>\n

3. Scope of procedure<\/strong><\/span><\/h2>\n\n\n\n\n
Unit Under Test Characteristics<\/span><\/td>\nPerformance Range<\/span><\/td>\nPerformance method<\/span><\/td>\n<\/tr>\n
\n
\n
\n
\n
\n

DC voltage Rise Time Bandwith Time Marker<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/td>\n

\n
\n
\n
\n
\n

Up to 130V<\/span>
\n< 300ps<\/span>
\nUp to 1.1GHz 1ns to 5s<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/td>\n

\n
\n
\n
\n
\n

Comparison to Multifunction Calibrator<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

4. Standard and supporting device<\/strong><\/span><\/h2>\n
\n
\n
\u2714\u00a0Multiproduct Calibrator FLUKE 5520A or equivalent. <\/span>
\n\u2714\u00a050 \u03a9 Feed-through terminator BNC<\/span><\/div>\n
\n

5. Environment conditions\u00a0<\/strong><\/span><\/h2>\n

Temperature: (18 \u00f7 28)\u00b0C<\/span><\/p>\n

\n
\n

Relative Humidity: (40 \u00f7 60)%RH<\/span><\/p>\n<\/div>\n<\/div>\n

6. Preparation\u00a0<\/strong><\/span><\/h2>\n
\n
\n
– Technician must be familiar with calibration techniques and the operator manual of the UUT being calibrated. <\/span>
\n– Connect UUT and test equipment to appropriate power source. Set all STANDBY \/ POWER ON and allow warm- up as required by the manufacturer’s instructions.<\/span>
\n\u00a0 Self \u2013 Test function.<\/strong><\/em><\/span>
\n– You can view the self-test results by pressing Utility -> System -> Self-Test Info.<\/span>
\n– If self-test Fail, do not perform calibration. Ensure that the problems are found and resolved, or notify customer.<\/span><\/div>\n<\/div>\n<\/div>\n

7. Perform\u00a0<\/strong><\/span><\/h2>\n

7.1 Input Impedance Test<\/strong><\/span><\/h3>\n
\n
\n
\n

– Connect the output of STD (for example, Fluke 5520A) to the oscilloscope channel 1 input, as shown fig1, Set\u00a0CH1: ON<\/span>
\n– Setting the UUT impedance level to be tested (for devices with multiple impedance levels).<\/span>
\n– Set the output impedance of the STD to match the impedance set on the UUT, example 50\u03a9.<\/span>
\n– Configure Vertical Scale follow Impedance input point.( Depending on the manufacturer and each model) \uf0d8 Setting STD Measurement: ON<\/span>
\n– Measure the input Impedance of the UUT with the STD. Record this value.<\/span>
\n– Setting STD Measurement: STBY<\/span>
\n– Repeat above steps for remains channels of the Oscilloscope.<\/span><\/p>\n<\/div>\n

7<\/strong><\/span>.2 DC gain Accuracy Test<\/strong><\/span><\/h3>\n
\n
\n
– Connect the output of STD to channel CH1 of UUT as figure 1.<\/span>
\n– Based on manufacturer\u2019s manual, set to Factory Default to recall the factory default for UUT. <\/span>
\n– Set the probe attenuation to 1:1 on the analog channel<\/span>
\n– Set up the oscilloscope<\/span>
\n– Adjust the horizontal scale to 200.0 us\/div.<\/em><\/strong><\/span>
\n– On UUT: set the Volts\/Div value follow table below:<\/span><\/p>\n\n\n\n\n
\n
\n
\n
\n

0.5mV\/div<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/td>\n

\n
\n
\n
\n

1mV\/div<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/td>\n

\n
\n
\n
\n

2mV\/div<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/td>\n

\n
\n
\n
\n

5mV\/div<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/td>\n

\n
\n
\n
\n

10mV\/div<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/td>\n

\n
\n
\n
\n

20mV\/div<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/td>\n

\n
\n
\n
\n

50mV\/div<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/td>\n<\/tr>\n

\n
\n
\n
\n

100mV\/div<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/td>\n

\n
\n
\n
\n

200mV\/div<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/td>\n

\n
\n
\n
\n

500mV\/div<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/td>\n

\n
\n
\n
\n

1V\/div<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/td>\n

\n
\n
\n
\n

2V\/div<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/td>\n

\n
\n
\n
\n

5V\/div<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/td>\n

\n
\n
\n
\n

10V\/div<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\n
\n
\n

Note: test points in table above can be changed according to manufacturer\u2019s manual or customer\u2019s requirement.<\/em><\/strong><\/span><\/p>\n

– On STD: set voltage value equal 7 times value of UUT. Example, UUT setting 1mV\/div, then STD setting is 7mV.<\/span><\/div>\n

– Press the [<\/em>Acquire<\/em>]<\/em><\/strong> key<\/span>
\n– Then press the Acq Mode<\/em><\/strong> softkey and select Averaging<\/em><\/strong><\/span>
\n– Then press the #Avgs<\/em><\/strong> softkey and set it to 64<\/span>
\n– Select a measurement for the average voltage.<\/span>
\n– Record voltage value of UUT and compare with STD, for each test point setting as above.<\/span><\/div>\n
– Repeat above steps for remains channels of the Oscilloscope.<\/span><\/div>\n
<\/div>\n