In SX Microcontrollers, SX/B Compiler and SX-Key Tool, Beau Schwabe wrote:

<SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana">Electronegativity,<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p>

<SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana">Just curious, what are you trying to do at sub-3V and presumably low current?<o:p></o:p>

<SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana">How much current are you expecting to deliver out of the system, and for how long?<o:p></o:p>

<SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana"> 

<SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana">[b]Perhaps this is a question of "Absolute Minimum Current" conservation rather than voltage.[/b]

<SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana">I once designed a data logger around a 16F84 that was configured in RC oscillator

<SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana">mode running <SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana">at about 10kHz ... essentially a "functioning sleep mode" (FSM)... to

<SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana">conserve power.  I don't see why something similar couldn't be applied to an SX.<o:p></o:p>

<SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana">When an event occurred one of the I/O pins would switch in a parallel resistor<o:p></o:p>

<SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana">to the RC oscillator increasing the speed to about 4MHz.  At this point other devices<o:p></o:p>

<SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana">were powered up...  RTC (Real Time Clock) and Memory to "log" the event.  Once<o:p></o:p>

<SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana">a time stamp and event status was logged into memory, everything would shut down<o:p></o:p>

<SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana">and go back to the 10kHz FSM mode.  <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" /><st1:place><SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana">Battery</st1:place><SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana"> life from a 3V lithium (CR2032) was about<o:p></o:p>

<SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana">4 months.

<SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana"> 

<SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana">In order for something like a data logger to work under these conditions, we need to

<SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana">know more information about what you are trying to accomplish.

<SPAN style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana"><o:p></o:p> 

<o:p>[3] [/3]</o:p>



 

 

 
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