#side(Hint) #author("2023-08-12T06:16:52+00:00","default:hiroshi","hiroshi") *Very Simple Electrostatic Driver [#t89b7c5e] #ref(PennyAmp1.jpg,left,wrap,around,15%) #ref(Penny_Driver.JPG,left,wrap,around,27%) If you are interested in testing your electrostatic actuators by applying a digital high DC voltage, you may want a compact voltage supply on your side. Or, if you would like to demonstrate your device outside of the lab, you may need one that works with batteries. Although the circuit shown here cannot regulate the output continuously, it can generate a voltage close to 100 V from three 1.5 V batteries and can switch the output by a 2 V input voltage. #clear EMCO DC-DC converter Q01-5 is used to convert the 4.5 V into 100 V DC voltage and transistors of high Vce0 (2SC3632 dead link, 2SA1413dead link--> see NEC page) are used to regulate the output. Similar types of DC-DC converters are available from PICO (5A100S more efficient). Capacitor C3 and resister (100k) emulate electrostatic micro actuator. The output voltage can swing up to ~90 V. #clear #ref(PennyDriver2k.JPG,left,around,wrap,50%) This is an input voltage curve trace (0 - 2 V, square input, 2 kHz) and that of output. There is a delay of 50 micro sec in the output. This circuit was found to operate at a frequency up to 6.76 kHz, limited by this delay. Slew rate was found to be 7.23 V/microsec (0 V --> 80 V). Quiescent current was about 0.1 mA. These performances are good enough to test most electrostatic micro actuators. //How long does it operate with AA dry batteries of 1000 mAh? Assuming that power consumption occurs only at the collector of Tr1, the quiescent current (when input is High) is calculated to be 100 V / 100 kOhm = 1 mA. If no power consumption occurs at other parts, the batteries will last 1000 mAh / 1 mA = 1000 hours. #clear *Improved Version [#he47de15] #ref(PennyDriverLowPower.JPG,left,around,wrap,40%) LED was to indicate the circuit in operation. Pennies and dime were used as heat sinks. This may be a low-power configuration since current does not flow through the push-pull stage due to the difference of biasing voltages.