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[Help] 1.75V sink voltage reference

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Hi,

I'm not sure why the first/series resistor is so low if the load is only ~1mA, 820 Ohms results in about 6mA at 5V, maybe I've misunderstood/am missing something. Parts like to be kept cool, so the less quiescent current, the better. Depends. Will the sensor inputs interact in any negative way? TL431 is robust as a real reference, I'd guess TLV is too. I use 1mA (+ load current + a little extra in case) with TL431 when only using it as a voltage reference. Perhaps a quad op amp with a one as a voltage follower buffer, fanning out into three other voltage follower buffers could be helpful and less parts.
 

My load is ~(-1mA). I liked the idea of decreasing amps for Iin. I will increase R3. This part is solved thanks.

Now my question is "can voltage follower opamps (vfo) sink 1.1mA instead sourcing ?"
 

Hi,

Now my question is "can voltage follower opamps (vfo) sink 1.1mA instead sourcing ?"
Did you read the Opamp datasheet? This is the most reliable place to find such information.

Look for:
* sink, source
* high drive, low drive
* output low voltage and current, table values and charts
* output high voltage and current, table values and charts

Klaus
 

Thanks KlausST,

Referring to LM741 Datasheet it can swing between +-15V and short circuit current is 25mA. Looks like it can sink. There is no clear sign.
Can we say it can sink too by looking at page 7, 7.2FunctionalBlockDiagram, Output connected to Q20 PNP BJT over 50ohm ? I'm seriously asking.

LM324 Quad Opamp Page 7 clearly says it can sink as you advised. Should I go for LM324 as d123 mentioned ?

One more question to learn terminology. Some opamp outputs can reach near supply voltages but some can not. Lets say we supply an opamp +-12V. But opamp sinus output can swing at +-10 before a saturation. That 2V, what is it called, what is the term ?

Thanks.
 

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