Microvalves are important flow-control devices in many standalone and integrated microfluidic applications. Polydimethylsiloxane (PDMS)-based pneumatic microvalves are commonly used but they generally require large peripheral connections that decrease portability. There are many alternatives found in the literature that use Si-based microvalves, but variants that can throttle even moderate pressures (1 bar) tend to be bulky (cm-range) or consume high power. This paper details the development of a low-power, normally-open piezoelectric microvalve to control flows with a maximum driving pressure of 1 bar, but also retain a small effective form-factor of 5 mm × 5 mm × 1.8 mm. A novel combination of rapid prototyping methods like stereolithography and laser-cutting have been used to realize this device. The maximum displacement of the fabricated piezoelectric microactuator was measured to be 8.5 μm at 150 V. The fabricated microvalve has a flow range of 0–90 μL min⁻¹ at 1 bar inlet pressure. When fully closed, a leakage of 0.8% open-flow was observed with a power-consumption of 37.5 μW. A flow resolution of 0.2 μL min⁻¹—De-ionized (DI) water was measured at 0.5 bar pressure.

Small delay defect (SDD) testing is expected to become more prevalent as technology nodes continue to shrink and design frequencies continue to increase. In this paper, we critically examine previously published methods for evaluating SDD coverage and identify their shortcomings as an accurate and practical coverage metric. We propose an accurate method for measuring the coverage of small delay defects by any given pattern set. We demonstrate that the proposed metric overcomes the identified shortcomings of previously published approaches. For several ISCAS and industrial circuits, we generate test patterns and compare their SDD coverage values using different methods. Experimental results also demonstrate that the proposed method is several times faster to compute. Finally, we evaluate different testing strategies for screening small delay defects.