[A method of medical device power supply maintenance].

Based on the circuit board, we draw its circuit diagram. By analyzing the circuit diagram, we maintain medical device power supply and achieve the troubleshooting goal quickly.

[Design of dynamic skin impedance detector for the back electrode of high frequency surgical equipment].

For the conventional high frequency(HF) surgical equipment, the contact impedance between the two back electrodes when they are gluing with skin is 50-200 Omega. If the contact impedance between the two electrodes is either too large or too small, an alarm is needed. This detector is designed not only to detect the contact condition between skin and the back electrodes, but also to monitor and alarm the dynamic change of the contact impedance.