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<?xml-stylesheet type="text/xsl" href="https://devzone.nordicsemi.com/cfs-file/__key/system/syndication/rss.xsl" media="screen"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:slash="http://purl.org/rss/1.0/modules/slash/" xmlns:wfw="http://wellformedweb.org/CommentAPI/" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Current spikes when DCDC is on</title><link>https://devzone.nordicsemi.com/f/nordic-q-a/14210/current-spikes-when-dcdc-is-on</link><description>Hi, 
 I use the nrf52 dk(PCA10040). When monitoring the current consumption of the advertising with the DCDC enabled, we see some current spikes. Why? 
 Here is two screenshot, one with the dcdc enabled and the other with the dcdc disabled:</description><dc:language>en-US</dc:language><generator>Telligent Community 13</generator><lastBuildDate>Wed, 01 Jun 2016 08:45:30 GMT</lastBuildDate><atom:link rel="self" type="application/rss+xml" href="https://devzone.nordicsemi.com/f/nordic-q-a/14210/current-spikes-when-dcdc-is-on" /><item><title>RE: Current spikes when DCDC is on</title><link>https://devzone.nordicsemi.com/thread/54282?ContentTypeID=1</link><pubDate>Wed, 01 Jun 2016 08:45:30 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:e12b8010-de14-470b-a050-5453182f705f</guid><dc:creator>Stian R&amp;#248;ed Hafskjold</dc:creator><description>&lt;p&gt;This is the regulator operating in refresh mode. From the &lt;a href="http://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52832.ps.v1.0/power.html?cp=2_2_0_16#concept"&gt;spec&lt;/a&gt;:&lt;/p&gt;
&lt;blockquote&gt;
&lt;ul&gt;
&lt;li&gt;Auto-controlled refresh modes for LDO and DC/DC regulators to maximize efficiency&lt;/li&gt;
&lt;/ul&gt;
&lt;/blockquote&gt;
&lt;p&gt;Both the LDO and DCDC have two modes of operation. Normal mode and refresh mode. Refresh mode is used when the current consumption is low in order to further maximize the efficiency. Refresh mode works by charging up internal caps regularly to provide power to the chip. So the spikes you see is the inrush current to the caps.&lt;/p&gt;
&lt;p&gt;Whether or not the regulator should be in normal mode or refresh mode is automatically controlled by the chip itself. So from your plots you can see that the chip decided that refresh mode is the most efficient when DCDC is enabled, and normal mode with LDO.&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: Current spikes when DCDC is on</title><link>https://devzone.nordicsemi.com/thread/54281?ContentTypeID=1</link><pubDate>Tue, 31 May 2016 22:52:12 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:f5f5ac46-0712-4d0d-95b7-7dcb27b741e9</guid><dc:creator>Dave_couling</dc:creator><description>&lt;p&gt;Looks like the DCDC circuit may be oscillating.&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item></channel></rss>