Measuring the low frequencies that are common in many real-world situations, such as biomedical or speedometer applications, is a challenge due to the long periods of the cycles. A medium-scale-integration (MSI) CMOS circuit (Fig. 1) can measure frequencies in the range of 0.33 to 3.00 Hz (equal to 20 to 180 RPM)...
Register or Sign in below to download the full article in .PDF format, including high-resolution graphics and schematics when applicable.