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interfaces:level [2017/01/15 02:46]
darron [I2C converter] 		interfaces:level [2022/08/01 17:09] (current)
darron [Resources]
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 ==== Level conversion ==== ==== Level conversion ====
 <wrap right> <wrap right>
-{{:interfaces:level1.jpg?200}}+{{:interfaces:level4.jpg?200|I2C}}
 </wrap> </wrap>
  
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 on a breadboard is to use a pre-built adapter. on a breadboard is to use a pre-built adapter.
  
-Two of the more popular types found at places like eBay +Two    popular types found on eBay 
-are two channel bi-directional I2C level converters and four+are the two channel bi-directional I2C level shifters and the four
 channel general purpose converters. channel general purpose converters.
  
-=== I2C converter ===+=== I2C level shifter === 
 +<wrap right> 
 +{{:interfaces:level1.jpg?200|Pickle Microchip PIC ICSP}} 
 +</wrap>
  
-These devices contain two mosfets with pull-ups resistors in the+These devices contain two mosfets with 10K pull-up resistors in the
 arrangement specified by the Philips I2C interfacing application note (link below). arrangement specified by the Philips I2C interfacing application note (link below).
  
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 There is a speed impact when using these device which have a slow rise time. For example, when using [[:projects:pickle|Pickle Microchip PIC ICSP]] it was found that raising the SLEEP configuration value to 8 was necessary. There is a speed impact when using these device which have a slow rise time. For example, when using [[:projects:pickle|Pickle Microchip PIC ICSP]] it was found that raising the SLEEP configuration value to 8 was necessary.
 +
 +=== General purpose 4 channel ===
 +<wrap right>
 +{{:interfaces:converter3.jpg?200|Pickle Microchip PIC ICSP}}
 +</wrap>
 +
 +These general purpose bi-directional devices feature four mosfets in the Philips application note arrangement with 10K pull-ups.
 +
 +== Pinout ==
 +
 +<code>
 +         HV4       LV4
 +         HV3       LV3
 +         GND       GND
 +HIGH VCC HV        LV  LOW VCC
 +         HV2       LV2
 +         HV1       LV1
 +</code>
 +
 +[[:projects:pickle|Pickle Microchip PIC ICSP]] was found to be more reliable when raising the SLEEP configuration value to 2 with this adapter.
 === Resources === === Resources ===
  
-[[http://www.nxp.com/documents/application_note/AN10441.pdf|Level shifting techniques in I2C-bus design]] +[[https://wiki.kewl.org/downloads/AN10441.pdf|Level shifting techniques in I2C-bus design]]