{"id":14989,"date":"2023-10-25T18:56:13","date_gmt":"2023-10-25T18:56:13","guid":{"rendered":"https:\/\/liquidinstruments.com\/?p=14989"},"modified":"2025-12-18T00:23:00","modified_gmt":"2025-12-18T00:23:00","slug":"impedance-measurements-with-mokugo-part-2-inductance","status":"publish","type":"post","link":"https:\/\/liquidinstruments.com\/application-notes\/impedance-measurements-with-mokugo-part-2-inductance\/","title":{"rendered":"Impedance measurements with Moku:Go Part 2: Inductance","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"<p>This application note presents an example and discussion of how to make accurate impedance measurements with a Moku:Go device. In <a href=\"https:\/\/liquidinstruments.com\/blog\/2023\/06\/30\/simplifying-impedance-measurements-with-mokugo-part-1-resistance\/\" target=\"_blank\" rel=\"noopener\">Part 1<\/a>, we explored the math of measuring resistance using voltage measurements from the software-defined Moku Frequency Response Analyzer. Now in Part 2, we&#8217;ll explore inductance measurements.<\/p>\n<h2>Using the Moku Frequency Response Analyzer<\/h2>\n<p>The Moku Frequency Response Analyzer drives a swept sine wave on the Moku outputs and simultaneously measures the received signal amplitude (or power) and phase on the Moku inputs. This data can be used to measure the transfer function of a system or device under test (DUT) and subsequently create a plot of amplitude and phase vs. frequency, commonly referred to as a Bode plot.<\/p>\n<h3>Frequency Response Analyzer: Voltage units<\/h3>\n<div>\n<p style=\"font-weight: 400;\">In the first part of this application note series [1], we discussed the dBVpp voltage measurement of a 1 V<sub>pp<\/sub> sine wave driven out from the Moku output and looped back into an input.<\/p>\n<p style=\"font-weight: 400;\">We determined that, when driven across the 1 M\u03a9 input of the Moku device, this can be used to capture a power measurement:<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-14990 size-full\" src=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.18.55-AM.png\" alt=\"when driven across the 1 M\u03a9 input of the Moku device, this can be used to capture a power measurement\" width=\"454\" height=\"110\" srcset=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.18.55-AM.png 454w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.18.55-AM-300x73.png 300w\" sizes=\"(max-width: 454px) 100vw, 454px\" \/><\/p>\n<\/div>\n<div>\n<p>&nbsp;<\/p>\n<p>Thus, 1 V<sub>pp<\/sub> expressed in dBV<sub>pp<\/sub> gives:<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-14991 size-full\" src=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.20.02-AM.png\" alt=\"1 Vpp expressed in dBVpp gives:\" width=\"446\" height=\"120\" srcset=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.20.02-AM.png 446w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.20.02-AM-300x81.png 300w\" sizes=\"(max-width: 446px) 100vw, 446px\" \/><\/p>\n<\/div>\n<p style=\"font-weight: 400;\">We then used this voltage ratio to accurately measure resistive impedance.<\/p>\n<h2>Inductance<\/h2>\n<h4>Two-port measurement<\/h4>\n<p style=\"font-weight: 400;\">For this example, we will measure a known inductor: a Wurth electronics part #7447021. This is a 100 \u03bcH inductor, specified at 10 kHz with a \u00a020% tolerance, as seen in Table 1.<\/p>\n<p>&nbsp;<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-14992 size-full\" src=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.21.23-AM.png\" alt=\"Table 1: Inductor specification from data sheet [2]\" width=\"1158\" height=\"110\" srcset=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.21.23-AM.png 1158w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.21.23-AM-300x28.png 300w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.21.23-AM-1024x97.png 1024w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.21.23-AM-768x73.png 768w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.21.23-AM-600x57.png 600w\" sizes=\"(max-width: 1158px) 100vw, 1158px\" \/><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: center;\"><strong>Table 1:<\/strong> Inductor specification from data sheet [2]<\/p>\n<p style=\"font-weight: 400;\">An example setup using Moku:Go is shown in Figure 1. For a two-port measurement, we use the first and second inputs. This allows for the inductive loading on the Moku:Go swept sine output. Like in the resistive example, we use a termination resistor on Moku Input 1 in order to ensure the power dissipation occurs across the DUT. To ensure minimal loading on the output, we will leave Moku Input 2 at its internal 1 M\u03a9 input resistance.<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-14993 size-full\" src=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.22.59-AM.png\" alt=\"Figure 1: Moku:Go measurement setup\" width=\"672\" height=\"580\" srcset=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.22.59-AM.png 672w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.22.59-AM-300x259.png 300w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.22.59-AM-600x518.png 600w\" sizes=\"(max-width: 672px) 100vw, 672px\" \/><\/p>\n<p style=\"text-align: center;\"><strong>Figure 1:<\/strong> Moku:Go measurement setup<\/p>\n<p style=\"font-weight: 400;\">The equivalent circuit, showing the Moku:Go input impedances, is shown in Figure 2.<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-14994 size-full\" src=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.23.48-AM.png\" alt=\"Figure 2: Two-port equivalent circuit\" width=\"998\" height=\"446\" srcset=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.23.48-AM.png 998w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.23.48-AM-300x134.png 300w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.23.48-AM-768x343.png 768w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.23.48-AM-600x268.png 600w\" sizes=\"(max-width: 998px) 100vw, 998px\" \/><\/p>\n<p style=\"text-align: center;\"><strong>Figure 2: <\/strong>Two-port equivalent circuit<\/p>\n<p style=\"font-weight: 400;\">R1 and R2 are the input impedances (50 || 1 M\u03a9 and 1 M\u03a9, respectively); the DUT is the inductor.<\/p>\n<p style=\"font-weight: 400;\">The Moku Frequency Response Analyzer will allow us to determine the phase of V<sub>1<\/sub> vs. V<sub>2<\/sub> across frequency, as well as the magnitudes.<\/p>\n<h2>Calculation<\/h2>\n<p style=\"font-weight: 400;\">Basic circuit theory tells us the inductor presents an inductive reactance and that this reactance and the Moku:Go 1 M\u03a9 input resistance in parallel with the termination resistor\u2019s 50 \u03a9 resistive impedance can be represented as a phasor diagram (Figure 3).<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-14995 size-full\" src=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.24.45-AM.png\" alt=\"Figure 3:\u00a0Phasor chart of impedance\" width=\"934\" height=\"498\" srcset=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.24.45-AM.png 934w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.24.45-AM-300x160.png 300w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.24.45-AM-768x409.png 768w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.24.45-AM-600x320.png 600w\" sizes=\"(max-width: 934px) 100vw, 934px\" \/><\/p>\n<p style=\"text-align: center;\"><strong>Figure 3:<\/strong>\u00a0Phasor chart of impedance<\/p>\n<p style=\"font-weight: 400;\">Where:<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-14996 size-full\" src=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.25.36-AM.png\" alt=\"equation\" width=\"244\" height=\"66\" \/><\/p>\n<p style=\"font-weight: 400;\">The resistance of the 1 M\u03a9 Moku:Go input in parallel with the 50 \u03a9 terminator resistor is R = 49.9975 \u03a9.\u00a0 Also, for an inductor:<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-14997 size-full\" src=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.26.06-AM.png\" alt=\"equation\" width=\"758\" height=\"84\" srcset=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.26.06-AM.png 758w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.26.06-AM-300x33.png 300w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.26.06-AM-600x66.png 600w\" sizes=\"(max-width: 758px) 100vw, 758px\" \/><\/p>\n<p>Thus,<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-14998 size-full\" src=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.26.30-AM.png\" alt=\"equation\" width=\"788\" height=\"94\" srcset=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.26.30-AM.png 788w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.26.30-AM-300x36.png 300w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.26.30-AM-768x92.png 768w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.26.30-AM-600x72.png 600w\" sizes=\"(max-width: 788px) 100vw, 788px\" \/><\/p>\n<p style=\"font-weight: 400;\">So, we can determine the inductance L if we measure the phase \u00d8\u00a0at frequency \u0192.<\/p>\n<h2>Measurement setup and result<\/h2>\n<p style=\"font-weight: 400;\">Figure 4 shows the Moku:Go bench setup. It takes just moments to set up the Frequency Response Analyzer instrument on the Moku: iPad or desktop app and to produce the plots of magnitude and phase vs. frequency.<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-14999 size-full\" src=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Picture1.jpg\" alt=\"Figure 4: Moku:Go bench setup with desktop app\" width=\"476\" height=\"428\" srcset=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Picture1.jpg 476w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Picture1-300x270.jpg 300w\" sizes=\"(max-width: 476px) 100vw, 476px\" \/><\/p>\n<p style=\"text-align: center;\"><strong>Figure 4:<\/strong> Moku:Go bench setup with desktop app<\/p>\n<p style=\"font-weight: 400;\">You can share the plots on the Moku: app by tapping the cloud button, and export screenshots and high-resolution .CSV formatted data to onboard memory, Dropbox, or email. In this case, we shared the data to a Dropbox folder. The exported screenshot is shown in Figure 5.<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-15000 size-full\" src=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/bdfsjhbdfs.png\" alt=\"Figure 5: Moku Frequency Response Analyzer sweep of a 100 \u03bcH inductor\" width=\"488\" height=\"272\" srcset=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/bdfsjhbdfs.png 488w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/bdfsjhbdfs-300x167.png 300w\" sizes=\"(max-width: 488px) 100vw, 488px\" \/><\/p>\n<p style=\"text-align: center;\"><strong>Figure<\/strong> <strong>5:<\/strong> Moku Frequency Response Analyzer sweep of a 100 \u03bcH inductor<\/p>\n<p style=\"font-weight: 400;\">The swept sine is generated from 1 kHz to 10 MHz on the Moku output Channel 1. The blue trace shows Channel 2 (V<sub>2<\/sub>), while the red trace is Channel 1 (V<sub>1<\/sub>).\u00a0 The Moku math channel is shown in orange and is configured to show (ch2 \u00f7 ch1). Several cursors have been added to measure the phase and magnitude at 10 kHz, 100 kHz, and 1 MHz.<\/p>\n<p style=\"font-weight: 400;\">The orange math channel cursors allow us to quickly see the phase difference, which comes from dividing Signal 1 by Signal 2, at our 10 kHz frequency of interest, to be \u00d8 = 6.6822\u00b0.<\/p>\n<p style=\"font-weight: 400;\">From <strong>Eq<\/strong><strong>(1)<\/strong>, we calculate X<sub>L<\/sub> = 5.86 \u03a9.<\/p>\n<p style=\"font-weight: 400;\">From <strong>Eq<\/strong><strong>(2), <\/strong>calculate the inductor value L = 93.2 \u03bcH.<\/p>\n<p style=\"font-weight: 400;\">This is well within the specification of 100 \u03bcH \u00b1\u00a020%.<\/p>\n<p style=\"font-weight: 400;\">While the inductor is specified at 10 kHz, we can also take our measurements from figure 5 at 100 kHz, where \u00d8 = 48.425\u00b0. Again, applying Eq (2), this gives L = 89.7 \u03bcH. As expected, the inductance outside of the specified frequency range is not as close to the designated 100 \u00b5H value, but still falls within our specified value range.<\/p>\n<p style=\"font-weight: 400;\">Since we used the Moku: desktop app to save the high-resolution Frequency Response Analyzer magnitude and phase data to a .CSV file via Dropbox, we can rapidly import this into Excel and, using Eq (2), produce a plot of inductance (blue) and phase (orange) vs. frequency, as seen in Figure 6.<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-15001 size-full\" src=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/jkhy-e1698251822376.png\" alt=\"Figure 6:\u00a0Inductance and phase vs. frequency\" width=\"448\" height=\"297\" srcset=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/jkhy-e1698251822376.png 448w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/jkhy-e1698251822376-300x199.png 300w\" sizes=\"(max-width: 448px) 100vw, 448px\" \/><\/p>\n<p style=\"text-align: center;\"><strong>Figure 6:\u00a0<\/strong>Inductance and phase vs. frequency<\/p>\n<p style=\"font-weight: 400;\">This clearly shows that above 100 kHz, the inductance falls off steadily until at around 5 MHz, where the inductance is effectively zero.<\/p>\n<p style=\"font-weight: 400;\">This occurs because a real-world practical coil inductor is not a perfect inductor. Rather, it has some resistance and capacitance. The equivalent circuit is shown in Figure 7.<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-15002 size-full\" src=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/rc\u2248.png\" alt=\"Figure 7: Inductor equivalent circuit\" width=\"330\" height=\"212\" srcset=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/rc\u2248.png 330w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/rc\u2248-300x193.png 300w\" sizes=\"(max-width: 330px) 100vw, 330px\" \/><\/p>\n<p style=\"text-align: center;\"><strong>Figure 7:<\/strong> Inductor equivalent circuit<\/p>\n<p style=\"font-weight: 400;\">A perfect inductor has impedance that linearly rises with frequency.\u00a0 But a real-world inductor has an effective parasitic capacitance in parallel (C<sub>epc<\/sub>) together with resistive elements R<sub>esr<\/sub> and R<sub>epr<\/sub>. R<sub>esr<\/sub> is sometimes quoted in datasheets as DC resistance and is the resistance of the wire coil. R<sub>epr <\/sub>is effective parallel or AC resistance. C<sub>epc<\/sub> is parallel capacitance due to the proximity of the wire coils.<\/p>\n<p style=\"font-weight: 400;\">Thus, there is a resonance frequency determined by:<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-15003 size-full\" src=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.34.53-AM.png\" alt=\"equation\" width=\"302\" height=\"128\" srcset=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.34.53-AM.png 302w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Screenshot-2023-10-25-at-9.34.53-AM-300x127.png 300w\" sizes=\"(max-width: 302px) 100vw, 302px\" \/><\/p>\n<p style=\"font-weight: 400;\">Again, referring to the inductor datasheet [2], we see that the inductor has a typical impedance characteristic showing resonance peak at around 5 MHz, reproduced in Figure 8.<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-15216 size-large\" src=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Typical-impedance-characteristics.png\" alt=\"Figure 8:\u00a0Wurth inductor typical impedance [2]\" width=\"700\" height=\"737\" srcset=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Typical-impedance-characteristics.png 1250w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Typical-impedance-characteristics-285x300.png 285w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Typical-impedance-characteristics-973x1024.png 973w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Typical-impedance-characteristics-768x809.png 768w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Typical-impedance-characteristics-300x316.png 300w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Typical-impedance-characteristics-600x632.png 600w\" sizes=\"(max-width: 700px) 100vw, 700px\" \/><\/p>\n<p style=\"text-align: center;\"><strong>Figure 8:\u00a0<\/strong>Wurth inductor typical impedance [2]<\/p>\n<p style=\"font-weight: 400;\">Because Moku devices make it easy to share the Frequency Response Analyzer data to a .CSV via Dropbox, we can readily use Excel to provide a plot of magnitude impedance vs. frequency from the magnitude of the math channel shown in Figure 5. From this data in Excel, we generate the plot, as shown in Figure 9.<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-15241 size-full\" src=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Mag-Impedance-vs-F-Plot.png\" alt=\"Figure 9:\u00a0Moku:Go measured impedance\" width=\"1126\" height=\"741\" srcset=\"https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Mag-Impedance-vs-F-Plot.png 1126w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Mag-Impedance-vs-F-Plot-300x197.png 300w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Mag-Impedance-vs-F-Plot-1024x674.png 1024w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Mag-Impedance-vs-F-Plot-768x505.png 768w, https:\/\/liquidinstruments.com\/wp-content\/uploads\/2023\/10\/Mag-Impedance-vs-F-Plot-600x395.png 600w\" sizes=\"(max-width: 1126px) 100vw, 1126px\" \/><\/p>\n<p style=\"text-align: center;\"><strong>Figure 9:\u00a0<\/strong>Moku:Go measured impedance<\/p>\n<p style=\"font-weight: 400;\">The resonance, as measured, is slightly above 5 MHz and the characteristics of the measurement are closely in line with the typical performance of Figure 8, taken from the manufacturer\u2019s datasheet.<\/p>\n<h2>Summary<\/h2>\n<p style=\"font-weight: 400;\">The software-defined Moku Frequency Response Analyzer can accurately measure the inductive impedance of a component over frequency. The Frequency Response Analyzer is available on FPGA-based Moku:Go, Moku:Lab, and Moku:Pro devices alongside a full suite of other software-defined instruments.<\/p>\n<p style=\"font-weight: 400;\">The results were shared via a .CSV file and Dropbox with the desktop Moku: app. We used Excel to plot both inductance and phase vs. frequency together with impedance vs frequency.<\/p>\n<p style=\"font-weight: 400;\">The calculated impedance at specified 10 kHz matches the component specification. Additionally, the plotted impedance vs. frequency closely matched the manufacturer\u2019s typical chart up to 10 MHz.<\/p>\n<h2>Questions or comments?<\/h2>\n<p>Contact us at <a href=\"mailto:support@liquidinstruments.com\">support@liquidinstruments.com<\/a>.<\/p>\n<h2>References<\/h2>\n<p><strong>[1] <\/strong>Impedance measurements with Moku:Go \u2013 Part 1: Resistance: <a href=\"https:\/\/liquidinstruments.com\/blog\/2023\/06\/30\/simplifying-impedance-measurements-with-mokugo-part-1-resistance\/\">https:\/\/liquidinstruments.com\/blog\/2023\/06\/30\/simplifying-impedance-measurements-with-mokugo-part-1-resistance\/<\/a><\/p>\n<p><strong>[2] <\/strong>Wurth Electronics 100 uH coil inductor data sheet: <a href=\"https:\/\/www.we-online.de\/katalog\/datasheet\/7447021.pdf\">https:\/\/www.we-online.de\/katalog\/datasheet\/7447021.pdf<\/a><\/p>\n<p><strong>[3]<\/strong> Moku:Go Frequency Response Analyzer user manual: <a href=\"https:\/\/download.liquidinstruments.com\/documentation\/datasheet\/instrument\/mokugo\/Datasheet-MokuGo-FrequencyResponseAnalyzer.pdf?hsCtaTracking=63c040ab-945b-4c57-8099-da36de04e026%7C4d6dcdbb-ae2b-4a98-ac23-6dbfb10f4c50\">https:\/\/download.liquidinstruments.com\/documentation\/datasheet\/instrument\/mokugo\/Datasheet-MokuGo-FrequencyResponseAnalyzer.pdf<\/a><\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"<p>This application note presents an example and discussion of how to make accurate impedance measurements with a Moku:Go device. In Part 1, we explored the math of measuring resistance using voltage measurements from the software-defined Moku Frequency Response Analyzer. Now in Part 2, we&#8217;ll explore inductance measurements. Using the Moku Frequency Response Analyzer The Moku [&hellip;]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":40,"featured_media":14304,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"content-type":"","footnotes":""},"categories":[5],"tags":[213,217,214,215,216,93],"class_list":["post-14989","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-application-notes","tag-bode-analysis","tag-fra","tag-impedance","tag-inductance","tag-inductor","tag-mokugo","site-category-frequency-response-analyzer","site-category-mokugo","site-category-oscilloscpe"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v27.0 (Yoast SEO v27.0) - https:\/\/yoast.com\/product\/yoast-seo-premium-wordpress\/ -->\n<title>Impedance measurements with Moku:Go \u2013 Part 2: Inductance<\/title>\n<meta name=\"description\" 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