LED panel meter

10-32 -- elektor october 1981 LCD panel meter Digital panel meters have one major snag and that is their "floating" input. This can cause problems resulting in display errors. The reason for this will be explained later. On the other hand, they also have many significant advan- tages: since they are based on ICs, they require very few external components and therefore take up little space. The IC already incorporates an automatic zero adjustment, an automatic polarity indicator, a clock oscillator and a reference voltage source. The IC used here can also drive a display, has pro- vision for an external reference voltage, indicate an over-range and measure the input voltage off-earth (although the latter will cause problems as mentioned LCD panel meter a versatile 31/2 digit display The use of digital voltmeters as panel meters is becoming increasingly popular these days. The version described here was originally designed for the barometer circuit published in the September issue, ...