+15 v, -15 v measured through r/3r voltage divider gives ~ 6.7 v, not 10 v as expected. attributed...
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![Page 1: +15 V, -15 V measured through R/3R voltage divider gives ~ 6.7 V, not 10 V as expected. attributed to myDAQ-internal connections associated with grounds](https://reader036.vdocuments.site/reader036/viewer/2022082817/56649de45503460f94adbad7/html5/thumbnails/1.jpg)
+15 V, -15 V measured through R/3R voltage divider gives ~ 6.7 V, not 10 V as expected.attributed to myDAQ-internal connections associated with grounds such as AGND.
to circumvent, use +15 V and nearby AGND to supply 15 V, rather than the 30 V orignallydesired.
as before, accuracy measurement can be performed using DMM channel, this time using 20 V scale. sample measurement reveals 14.90 +/- 0.09 V (compare to 30.0 +/- 0.4 V from last lecture)
now, let’s measure the precision of the +15 V power supply:a) for observations every 5 µs (200 kS/s)b) for observations every 0.1 snote: DMM is not fast enough for either (a) or (b), and even if it was, coarse resolution on the DMM complicates evaluation of precision
use R/2R voltage divider in conjunction with ai0
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J = 2x_1 = V_PSx_2 = V_ai0r = V_measured = x_1 + x_2 = V_ai0 + V_PS
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3-minute records
ai0 shortedai0 monitoring
15V through V divider
![Page 4: +15 V, -15 V measured through R/3R voltage divider gives ~ 6.7 V, not 10 V as expected. attributed to myDAQ-internal connections associated with grounds](https://reader036.vdocuments.site/reader036/viewer/2022082817/56649de45503460f94adbad7/html5/thumbnails/4.jpg)
to myDAQ 1
to myDAQ 1
to myDAQ 2
to myDAQ 2
2.26 kΩ