Standard use of electronic devices in work

The circuit is divided into analog amplifier and digital counter. The analog amplifier adopts 741 operation amplifier. The single-supply connection forms the same direction amplifier. The sine signal is sent to the amplifier to generate the corresponding pulse train and is used as the clock signal of the decimal counter. There is a need for dual trace display to observe the input and output waveforms of the amplifier. The digital part is a decimal counter and is decoded on the digital tube after being decoded by the seven-segment decoder. Here we need to observe the output of the QAQD, a decimal counter, with a total of four logic signals. Since it is a digital-analog hybrid circuit, if we want to compare the analog pulse signal with the four-way count signal, we need a six-channel digital-analogue hybrid display oscilloscope. And the mixed digital oscilloscope in multisim8 can exactly meet the requirements.

First open Multisim8, select the required components and power supply and connect them. Select the Agilent Function Generator, Agilent Multimeter, Agilent Oscilloscope in the virtual instrument bar and place it in place. Turn on the function generator power supply and select the sine signal with a peak-to-peak value of 380mV and a frequency of 1KHz as the input signal for the analog amplifier. Connect the two analog channels of the oscilloscope to the input and output of the analog-amplifier mixed-signal analog circuit example. Turn on the oscilloscope power supply, press the 1 and 2 channel buttons, and press the number 07 channel button. For example, the corresponding button indicators turn green. Adjust the waveform to the appropriate position, or press the oscilloscope button AutoScale to set the automatic scale. Observe the input and output waveforms of the amplifier and change the size of resistor R2 until the amplifier output is a pulse train. Connect the oscilloscope's logic channel D0D4 to the output QAQD of the decimal counter 74HC190N and the carry-out simulation result RCO. Observe the timing relationship between the counter outputs and compare the phase with the output of the analog part. You can start and stop continuous acquisition with RunStop. Need to measure the analog waveform and digital waveform related parameters, such as amplitude, frequency, level, etc., you can use the digital oscilloscope QuickMeas button and press the button below the screen. It can be seen from the above that the counter is triggered by a rising edge, and at the same time that the counter counts to 9, the carry RCO is valid and a negative pulse occurs. Connect the digital multimeter to the counter output QA, turn on the digital multimeter power supply, and measure the frequency of the periodic waveform of the QA output as 500Hz. You can also measure the frequency and effective value of the analog frequency in other cycles.

It can be seen that the use of modern virtual simulation instruments enables electronic engineers or teaching workers to use less resources, be more efficient, and perform simulations closer to the actual situation. With the development of simulation virtual instruments, its further improvement in functional completeness, use of realism, software algorithms, etc., combined with the growing development of computer technology, will inevitably become an indispensable area for computer-aided analysis and electronic education in electrical engineering. Powerful tool.