Resistive damping implementation improve controllability in ohmic RF-MEMS switches

This paper presents in detail the entire procedure in calculating the bias resistance of an ohmic RFMEMS switch, controlled under resistive damping. (Charge drive technique). In case of a very stiff device, like the North Eastern University (NEU) switch, the actuation control under resistive damping is the only way to achieve controllability. Due to the short switching time as well as the high actuation voltage, it is not practical to apply a tailored control pulse (Voltage drive control technique). Implementing a bias resistor of 33MΩ in series with the voltage source, the impact velocity of the cantilever has been reduced to 13.2 cm/sec from 65.9cm/sec, with only a small increase in the switching time (3.47μs from 1.72μs), eliminating bouncing and high initial impact force during the pull-down phase. During the release phase the amplitude of bouncing has been also reduced to 174nm from 255nm, proving that incorporating resistive damping significant improvement in both switching operation phases of the switch can be achieved.