Circuits & Schematics - Measurement - 9

Besides its mind-boggling simplicity and programmable resolution, the chief attribute of the Shannon decoder DAC (SD) is speed ( Ref. 1 ), converting a serial n-bit digital stream into an analog signal in just nT seconds where T = 1 bit time. Of ...

It’s just an unavoidable fact: electronic components’ parameters drift with temperature. Even the most stable voltage references, op amps, crystal oscillators, etc., have non-zero temperature coefficients. These effects can be mitigated ...

Filter, audio, and RF-communications testing often require a random noise source. Figure 1’s circuit provides an RMS-amplitude regulated noise source with selectable bandwidth. RMS output is 300 mV with a 1 kHz to 5 MHz bandwidth, selectable ...

Figure 1 is a “charge pump” type V/F converter specifically designed to run from a 3.3 V rail. A 0 V to 2 V input produces a corresponding 0 kHz to 3 kHz output with linearity inside 0.05%. To understand how the circuit works assume ...

This article describes an active load circuit that can be used to simulate a battery in any state of charge. The battery simulator provides a constant-voltage load for a battery-charging circuit, independent of applied charging current. The ...

It is often desirable to determine a battery’s internal resistance to evaluate its condition or suitability for an application. Accurate battery resistance determination is complicated by inherent capacitive terms which corrupt results taken ...

Self-heated thermal airflow sensors are simple, cheap, rugged, and sensitive. However, they exhibit an airspeed to sensor temperature response ( King’s Law ) that is very nonlinear, as shown in Figure 1. Figure 1. The TO-92 junction ...

I was reminded recently of a tester I designed years ago. At the time, I wanted to build “The Ultimate Continuity Tester,” and I established a wish list of all the features I required: A “real continuity” tester. Too many ...

Low-power, low-cost ceramic piezoelectric rate gyros are available, but they lack the low-temperature-coefficient characteristics of their quartz counterparts. However, you can use a servo amplifier to remove the dc level shift due to ...

Figure 1’s circuit achieves a wider dynamic range and higher output frequency than any commercially available voltage to frequency (V-F) converter. Its 100 MHz fullscale output (10% overrange to 110 MHz is provided) is at least ten times ...