Need less than 3.3v

Comments

• Tricky Nekro Posts: 218

  2007-05-20 15:45 edited 2007-05-20 15:45

  Use an LM317... First use a trimmer-pot and get the desired voltage... then replace it with resistors and you 're jet!!!
  
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• Tracy Allen Posts: 6,657

  2007-05-21 01:27 edited 2007-05-21 01:27

  It depends on the current. True, a silicon diode has a forward voltage drop of 0.6 volts, but that is only at a current of 10s of milliamps. That sensor claims a current drain of only 3.5 microamps, and the forward drop of a diode at that current will be much much less than 0.6. It may be that the sensor draws pulses of current when it actually makes a measurement, and often the last thing you want on one of these sensors is a changing voltage at that very instant.
  
  It will be better off with a voltage regulator. There are some nice low dropout, low quiescent current 2.7 volt fixed regulators around. I like the LT1761es5-2.7, at 20 uA quiescent, and there are others at down to 4 or 5 microamps quiescent.
  
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• PJAllen Banned Posts: 5,065

  2007-05-21 01:59 edited 2007-05-21 01:59

  Here's my idea (attached.)

  

  

  2V6_out.GIF

  272 x 152 - 2K

  2V6_out.GIF 1.7K
• Dennis Ferron Posts: 480

  2007-05-21 08:10 edited 2007-05-21 08:10

  Just configure an op-amp as a voltage buffer (negative tied to output, positive tied to resistor-divider) and use the output of the op-amp as a power supply.
  
  Or use the 317.