In high-vacuum measurement, cold-cathode ionization gauges have been widely used due to their unique advantages such as being simple and robust, low outgassing, x-ray effects, and so on. But during the measuring process, they show that a considerable pump effect, contamination buildup, and the heating and sputtering of the electrode surface from discharge can also become a serious problem at higher measured pressures. In such circumstances, pulsed operation is a good solution. However, the lowest measurable pressure of cold-cathode ionization gauges in pulsed operation is hard to extend, which limits its application. But if the measurable range of the cold-cathode gauge is divided into two regions, the low-pressure region where it is operated in dc discharge mode to ensure its lowest measurable pressure and the high-pressure region where it is operated in pulsed-discharge mode to reduce its above disadvantages at high pressures, the problem can be well solved. This article describes a pulsed high-voltage generating circuit controlled by a single-chip CPU to perform such, a hybrid discharge in an inverted-magnetron gauge. With this circuit, the following problems of an inverted-magnetron gauge were investigated: the difference between pulsed-discharged mode and dc discharge mode, one method of extending the low measurable pressure limit in pulsed-discharge mode, the volt-current characteristics at different pressures, and constant-current pulsed-discharge measurement at pressures above 2 x 10(-2) Pa. (c) 2007 American Vacuum Society.