{"id":728,"date":"2015-02-19T22:19:10","date_gmt":"2015-02-19T16:49:10","guid":{"rendered":"http:\/\/brainstorms.in\/?p=728"},"modified":"2015-02-28T14:10:53","modified_gmt":"2015-02-28T08:40:53","slug":"si5351-breakout-board","status":"publish","type":"post","link":"https:\/\/brainstorms.in\/?p=728","title":{"rendered":"A simple Si5351A breakout board"},"content":{"rendered":"

I have been toying with the idea of making a Si5351A breakout board ever since I saw the chip details on Silicon labs web site. It seems\u00a0 SI5351A is an ideal choice for Variable Frequency Oscillator (VFO) for a homebrewed radio.\u00a0 The SI5351 is an i2c programmable any frequency clock generator. The chip can\u00a0 generates up to 8 non-integer-related\u00a0 frequencies from 8 kHz to 160 MHz depending on the model. There are 3 different variations of the chip currently available.\u00a0 For the home brewer SI 5351A looks promising as it is available in a 10 pin MSOP package.<\/p>\n

For the ham radio home brewer, such a chip which can be programmed over many ham bands offer\u00a0 numerous possibilities.\u00a0\u00a0 The most obvious choice would be\u00a0 as a VFO. Currently, the analog devices DDS chips are ruling the market. Compared to them the Silicon Labs chips are cheaper and less cumbersome to handle. I am yet to see the noise performance of these two chips compared.<\/p>\n

In fact, there are a couple of commercial Si5351A breakout boards \u00a0 targeted at the\u00a0 home brewer. They cost around 10$. But the chip itself cost only 1.33$\u00a0 on the Silicon Labs website and you need only a few\u00a0 additional components to complete the board. The total cost need not be more than 3 $.\u00a0 Along with a cheap Arduino clone, Si5351A gives you lot of flexibility. An added advantages is that the SI5351A\u00a0 has three independent programmable clock generators. You can combine\u00a0 the\u00a0 VFO and \u00a0 BFO\u00a0 into a single chip.<\/p>\n

My idea was to build a single side PCB so that any one can build one via toner transfer. Last week,\u00a0 I had a long\u00a0 chat\u00a0 with my friend and colleague Amal Dev<\/a>\u00a0 about designing\u00a0 a simple board.\u00a0 The board routing was done by Amal Dev on eagle,\u00a0 We have\u00a0 designed an experimental single sided board and it may not be conforming to RF design principles always.<\/p>\n

For the interested home brewer a\u00a0 toner transferable image is\u00a0 here<\/a>. \u00a0\u00a0 You can\u00a0 buy the\u00a0 SI5351 from RS components<\/a>\u00a0 or from Mouser<\/a>.\u00a0 The board is to be powered from a 5v source.\u00a0 The SI5351A needs 3.3v for its operation. The LM1117 is used for generating this.\u00a0 Note that the LM1117\u00a0 is SMD and is soldered on the copper side.\u00a0 The two MOSFETs ( BS170)\u00a0\u00a0 are used to convert the I2C levels from 5v to 3.3v.\u00a0 Check the pin outs before you solder.\u00a0 The board can be directly powered from an arduino.<\/p>\n

For programming the board you can try the example code from Hansummers<\/a>.\u00a0 Alternately you can try the excellent si5351 arduino library.\u00a0 Tom Hall AK2B<\/a> has some\u00a0 sample sketches using this library. Please note that I2C address of the chip may be different from those found in the above code. Please use an I2C scanner<\/a>\u00a0 to find out your chips address and then modify your code accordingly.<\/p>\n

\"si5351<\/a>
Schematic of si5351 breakout board. Q1 and Q2 are bs170. The regulator is a smd lm1117<\/figcaption><\/figure>\n

 <\/p>\n

 <\/p>\n

\"Board-Total\"<\/a>
Si 5351 board.<\/figcaption><\/figure>\n
\"si2\"<\/a>
Component Placement on the Si5351 break out board.<\/figcaption><\/figure>\n

The pin out of the SI5351A is shown below.<\/p>\n

\"si5351_pinout\"<\/a><\/p>\n

A special thanks to Amogh Desai <\/a>who tested the first version\u00a0 and reported couple of errors.\u00a0 Further comments and error reports are welcome.<\/p>\n","protected":false},"excerpt":{"rendered":"

I have been toying with the idea of making a Si5351A breakout board ever since I saw the chip details on Silicon labs web site. It seems\u00a0 SI5351A is an ideal choice for Variable Frequency Oscillator (VFO) for a homebrewed radio.\u00a0 The SI5351 is an i2c programmable any frequency clock generator. The chip can\u00a0 generates… Continue reading A simple Si5351A breakout board<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[],"class_list":["post-728","post","type-post","status-publish","format-standard","hentry","category-ham-radio"],"_links":{"self":[{"href":"https:\/\/brainstorms.in\/index.php?rest_route=\/wp\/v2\/posts\/728","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/brainstorms.in\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/brainstorms.in\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/brainstorms.in\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/brainstorms.in\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=728"}],"version-history":[{"count":11,"href":"https:\/\/brainstorms.in\/index.php?rest_route=\/wp\/v2\/posts\/728\/revisions"}],"predecessor-version":[{"id":748,"href":"https:\/\/brainstorms.in\/index.php?rest_route=\/wp\/v2\/posts\/728\/revisions\/748"}],"wp:attachment":[{"href":"https:\/\/brainstorms.in\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=728"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/brainstorms.in\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=728"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/brainstorms.in\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=728"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}