New-Tech Europe Magazine | July 2016 | Digital edition

cost parts.

only one instrument to program. This eliminates the need to synchronize multiple instruments and allows the engineer to focus on making the measurement. However, instrument designers are only beginning to take on the challenge of creating instruments capable of providing the level of power needed to energize a wireless IoT device without sacrificing the ability to measure both very low load currents and much higher active load currents accurately and with high resolution. Such instruments are only now entering the market in the form of power supplies with integrated precision measurement capabilities (Figure 3). In order to measure very low standby

or sleep mode currents accurately, a power supply/measurement instrument must be capable of DMM-quality measurements with up to 6½ digits of resolution. When making high current measurements, it has to capture current pulses as short as hundreds of microseconds. Also, because some devices, such as implantable medical sensors or other portable, battery-powered devices, have a power-up load sequence and a power-down sequence, similar to the one shown in Figure 4, the instrument chosen must have the triggering capabilities needed to make multiple, synchronized measurements at each state of the power-up or power-down cycle.

A single instrument solution for multiple measurement challenges Obviously, most design and test engineers would prefer a solution that’s less complicated to implement than configuring a test setup with a DC power supply to provide the source voltage, a sense resistor, a DMM, an oscilloscope, an SMU instrument, and a switching system to tie them all together. If they can make the measurements they need with only a single instrument, testing can begin sooner because there is less equipment to set up (Figure 2). Automating the measurement is simpler as well with

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