I have LT1019ACN8-5 IC output is 5V. I am using this IC to get Vref 3.3 for the ADS8320. is it ok if i use a voltage divider to the output pin to regulate 5v to 3.3v. Is it acceptable ?

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    \$\begingroup\$ Is your load absolutely constant? \$\endgroup\$ – PlasmaHH May 16 '17 at 14:56
  • \$\begingroup\$ @PlasmaHH Load --> I am using output to feed Vref of the ADS8320 [ti.com/lit/ds/symlink/ads8320.pdf] IC \$\endgroup\$ – vassidefuk May 16 '17 at 14:58
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    \$\begingroup\$ Kind of a waste of a nice reference. The errors you get from the divider resistors will swamp the accuracy of the reference. \$\endgroup\$ – John D May 16 '17 at 15:08
  • \$\begingroup\$ also i need to know difference between shunt and series type of these voltage reference ICs \$\endgroup\$ – vassidefuk May 16 '17 at 17:02

The reference input of the ADS8320 draws varying current depending on the sample rate, like many ADC converters without reference buffers.

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At, say, 25uA, a source resistance of only 2 ohms will result in 1 lsb of change in reading due to the reference current. It's usually best to use a buffer that has low noise output. Sometimes this is surprisingly expensive to do right, although fortunately it's only 16 bits.

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