Oscilloscope testing applications in medical equipment

agitek2017

Oscilloscope testing applications in medical equipment [Copy link]

Recently, a medical unit consulted about the application of targeted treatment test of high-frequency and high-voltage signals. It is necessary to realize the superposition of high-frequency sine wave and low-frequency triangle wave. The sine signal is 10kHz-100kHz, and the triangle wave signal is tens of hertz. The output voltage of the sine signal is several volts, and the triangle wave is in the millivolt level. It is then distributed to the laser for driving and oscilloscope observation through a phase-locked amplifier. Previously, the customer used Tektronix's old AFG1K series function generator and old TBS1K oscilloscope. The function generator has no channel automatic superposition function, and the oscilloscope screen is also small. External power supply is required to connect high-voltage probes and current probes, which is very inconvenient.

Through technical exchanges with the customer, we learned that the customer's previous superposition of 2-channel sine and triangle wave signals was simply achieved using a BNC tee, which was unable to adjust the phase difference and the output amplitude value was often incorrect. In addition, the customer's old oscilloscope screen was too small to perform FFT to observe the high-order harmonics of the signal, nor was it possible to connect high-voltage probes and current probes to accurately measure the output power of the equipment.

High-frequency electromagnetic waves are a highly precise targeted treatment technology and have become an indispensable new treatment method in the medical industry. They have the advantages of being targeted, minimally invasive, having few toxic side effects, being repeatable, and not producing drug resistance. Therefore, they have very high requirements for the frequency and power control of the signal.

In response to the above test problems, we provided the laboratory with a test solution of AFG31000 function generator + TBS2000B series oscilloscope and provided them with an on-site demonstration.

The triangular wave and sine wave superposition signals required by customers for test experiments can be easily set through the CH1 ADD channel at the back end of the function generator to perform waveform superposition settings and amplitude and phase settings. The TBS2000B oscilloscope has 15 horizontal grids and a 9-inch WVGA color display, which can very intuitively and clearly display the state of the waveform and long-term observation. Using the improved FFT function, the purity and frequency distribution of the superimposed waveform can also be effectively seen. In addition, the VPI interface of TBS2000B and the direct power supply and automatic configuration of the high-voltage differential probe and current probe can accurately analyze and measure the voltage, current, and power of the DUT device.

Extended Application:

The TBS2000B oscilloscope + high-voltage differential probe + current probe test solution can also be applied to embedded systems, switching inverters, circuit board development and design, ventilator & oxygen concentrator circuit control, surgical robots, uninterruptible power supplies, etc.

Medical Device Development and Design Requirements

1. High-definition large screen and long-term monitoring.

2. Easy to connect and simple to operate.

3. High precision requirements and high degree of automation.

4. Strong expansion function, supporting high voltage and current safety testing.

5. The function generator can operate with two channels superimposed.

6. The function generator supports hand-drawn waveform output, which greatly reduces the time for R&D and design.

System Configuration Reference