DMM Is an Understatement

摘要

The amount of design and development money supporting new DMM functionality ensures that you will continue to see innovative improvements for many years. To determine the best DMM for your needs today, however, a few guidelines may help.rnFirst, determine which basic measurement capabilities you need. Do you require inductance and capacitance, or are they just nice-to-have features and not really necessary? This is important because several very good DMMs dornnot offer inductance and capacitance. If you do need to make these measurements, can you do so with a DMM-any DMM? Perhaps you need an LCR meter if the measurements must be made with the components biased as they would be in operation.rnNext, find a model having the extra features you want, such as data logging or dual/differential temperature measurement. And try to find one that also has a graphic display. Quarter VGA displays have become fairly common in DMMs, and they offer much greater flexibility. Some models actually display waveforms or trends in logged data. Even if the graphical capability isn't exploited, this type of display supports multiple, simultaneous readouts so you can compare this reading and the previous one. Or, you can view voltage, current, and a related parameter such as frequency.rnFinally, attempt to future-proof your purchase as much as possible withoutrncompromising the present requirements or budget. A DMM that provides a switching capability or is modular so it can be mixed with other functions is a good choice. On the other hand, given the relatively low cost of a DMM and the continuing feature innovation, you may choose to buy what you need now and address new applications as they arise.