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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>nRF52840 DK not starting when nPM1300 VBAT = 2.7 V</title><link>https://devzone.nordicsemi.com/f/nordic-q-a/125588/nrf52840-dk-not-starting-when-npm1300-vbat-2-7-v</link><description>Hello, 
 I have connected the nRF52840 DK to the nPM1300 EVK , with the DK powered from BUCK1 output of the nPM1300. 
 When I supply 3 V or higher to the VBAT pin of the nPM1300 (using an external supply), the nRF52840 DK powers up correctly and I can</description><dc:language>en-US</dc:language><generator>Telligent Community 13</generator><lastBuildDate>Tue, 16 Dec 2025 15:01:27 GMT</lastBuildDate><atom:link rel="self" type="application/rss+xml" href="https://devzone.nordicsemi.com/f/nordic-q-a/125588/nrf52840-dk-not-starting-when-npm1300-vbat-2-7-v" /><item><title>RE: nRF52840 DK not starting when nPM1300 VBAT = 2.7 V</title><link>https://devzone.nordicsemi.com/thread/557111?ContentTypeID=1</link><pubDate>Tue, 16 Dec 2025 15:01:27 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:14eb01b5-b520-4195-af60-941fd57e8cab</guid><dc:creator>Ressa</dc:creator><description>&lt;p&gt;Hi,&amp;nbsp;&lt;br /&gt;&lt;br /&gt;No problem. Based on the table I shared in previous message, to get 1.8 V on VOUT2 you should use resistor value of 4.7 K Ohm not 47 K ohm on VSET2.&lt;br /&gt;&lt;br /&gt;Best regards,&lt;br /&gt;Ressa&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: nRF52840 DK not starting when nPM1300 VBAT = 2.7 V</title><link>https://devzone.nordicsemi.com/thread/556929?ContentTypeID=1</link><pubDate>Sun, 14 Dec 2025 10:23:07 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:90b52927-4f67-4ca7-b038-709dee62a775</guid><dc:creator>Sagar Patel</dc:creator><description>&lt;p&gt;Sorry for late reply, Due to medical issue.&lt;/p&gt;
&lt;p&gt;Can send me your mail id so that i can sent you the schematic for review ?&lt;/p&gt;
&lt;p&gt;&lt;/p&gt;
&lt;p&gt;&amp;nbsp;&lt;img style="max-height:240px;max-width:320px;" src="https://devzone.nordicsemi.com/resized-image/__size/640x480/__key/communityserver-discussions-components-files/4/pastedimage1765707705570v1.png" alt=" " /&gt;&lt;/p&gt;
&lt;p&gt;&lt;/p&gt;
&lt;p&gt;For VSET we have used 47K register, please check the screenshot attached.&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: nRF52840 DK not starting when nPM1300 VBAT = 2.7 V</title><link>https://devzone.nordicsemi.com/thread/554786?ContentTypeID=1</link><pubDate>Wed, 19 Nov 2025 12:33:20 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:b7185af9-764b-451e-a920-eb4a596d48eb</guid><dc:creator>Ressa</dc:creator><description>&lt;p&gt;Hi,&lt;br /&gt;&lt;br /&gt;Thanks for contacting us.&amp;nbsp;&lt;br /&gt;If you would like, we can review your schematic in case there might be some hardware issue. For that you just need to upload the schematic here. I make the ticket private so that the schematic will be visible to just me (and Nordic employees).&amp;nbsp;&lt;br /&gt;* Just wondering what is the resistor values used&amp;nbsp;for VSET pins on nPM1300 (VSET1 and VSET2)? If VBAT voltage gets closer to the voltage set by resistors, you might not get exact value you would expect, there will be some voltage drop.&lt;br /&gt;&lt;br /&gt;&lt;img style="max-height:240px;max-width:320px;" src="https://devzone.nordicsemi.com/resized-image/__size/640x480/__key/communityserver-discussions-components-files/4/pastedimage1763555534585v1.png" alt=" " /&gt;&lt;br /&gt;&lt;br /&gt;&lt;br /&gt;Best regards,&lt;br /&gt;Ressa&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: nRF52840 DK not starting when nPM1300 VBAT = 2.7 V</title><link>https://devzone.nordicsemi.com/thread/554441?ContentTypeID=1</link><pubDate>Sat, 15 Nov 2025 09:31:57 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:03542d8f-63d8-4238-9fa0-9fc3328c6179</guid><dc:creator>Sagar Patel</dc:creator><description>&lt;p data-start="177" data-end="401"&gt;I initially tested this behavior on our &lt;strong data-start="217" data-end="233"&gt;custom board&lt;/strong&gt;, in that nrf52840 with npm1300,&amp;nbsp; where the setup did not work as expected.&lt;br data-start="276" data-end="279" /&gt; To isolate the issue, we are now testing the same configuration on the &lt;strong data-start="350" data-end="365"&gt;nRF52840 DK&lt;/strong&gt; connected to the &lt;strong data-start="383" data-end="398"&gt;nPM1300 EVK&lt;/strong&gt;.&lt;/p&gt;
&lt;p data-start="403" data-end="625"&gt;Could you please advise if there are any specific checks required on the &lt;strong data-start="476" data-end="493"&gt;hardware side&lt;/strong&gt;?&lt;br data-start="494" data-end="497" /&gt; Additionally, if any &lt;strong data-start="518" data-end="566"&gt;software configurations or register settings&lt;/strong&gt; need to be modified, your guidance would be appreciated.&lt;/p&gt;
&lt;p data-start="627" data-end="936"&gt;We are currently using a &lt;strong data-start="652" data-end="671"&gt;battery profile&lt;/strong&gt; with a voltage range of &lt;strong data-start="696" data-end="715"&gt;2.9 V (minimum)&lt;/strong&gt; to &lt;strong data-start="719" data-end="738"&gt;4.5 V (maximum)&lt;/strong&gt;.&lt;br data-start="739" data-end="742" /&gt; As part of troubleshooting, I also modified the minimum voltage setting from &lt;strong data-start="819" data-end="837"&gt;2.9 V to 2.7 V&lt;/strong&gt; to verify whether this would affect the operation, but the device still does not start at 2.7 V.&lt;/p&gt;
&lt;p data-start="938" data-end="1002"&gt;Thank you for your assistance and any further recommendations.&lt;/p&gt;
&lt;p data-start="1004" data-end="1031"&gt;Best regards,&lt;/p&gt;
&lt;p data-start="1004" data-end="1031"&gt;Sagar Patel&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: nRF52840 DK not starting when nPM1300 VBAT = 2.7 V</title><link>https://devzone.nordicsemi.com/thread/554423?ContentTypeID=1</link><pubDate>Fri, 14 Nov 2025 17:26:21 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:a4c5f632-8654-44d4-acce-084721740d08</guid><dc:creator>Menon</dc:creator><description>&lt;p&gt;Hello,&lt;/p&gt;
&lt;p&gt;I don&amp;#39;t think this issue is related to any register configuration. Might be that 2.7 V is not sufficient for the DK to function properly. While that voltage range is acceptable for the nRF52840 SoC itself, the Development Kit especially with the onboard debugger requires a higher voltage to operate correctly.&lt;/p&gt;
&lt;p&gt;If you&amp;#39;re using 2.7 V only as a test for your custom hardware, it may work for your design, but I doubt it will work reliably on the DK.&lt;/p&gt;
&lt;p&gt;Kind regards,&lt;br /&gt; Abhijith&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item></channel></rss>