Author Topic: Negative lm399 voltage reference  (Read 1990 times)

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Offline rigrunnerTopic starter

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Negative lm399 voltage reference
« on: January 30, 2016, 07:54:11 pm »
Searching throws up lots of reference circuits using LM399 but i haven't come across a simple negative reference.
Is this the simplest way to get a buffered negative reference from an LM399?


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Online Zero999

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Re: Negative lm399 voltage reference
« Reply #1 on: January 30, 2016, 08:29:33 pm »
That should work. Why do you think it should be a problem?
 

Offline rigrunnerTopic starter

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Re: Negative lm399 voltage reference
« Reply #2 on: January 30, 2016, 08:40:53 pm »
It does work. I have it on a breadboard at the moment.
I don't think there will be an issue with it but i thought i'd ask.
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Offline Andreas

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Re: Negative lm399 voltage reference
« Reply #3 on: January 30, 2016, 08:55:14 pm »
Hello,

you have only to take care that the negative heater pin (Pin 4) has equal or more negatrive voltage than the anode pin of the reference (Pin 2).

With best regards

Andreas
 

Offline rigrunnerTopic starter

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Re: Negative lm399 voltage reference
« Reply #4 on: January 30, 2016, 10:58:54 pm »
you have only to take care that the negative heater pin (Pin 4) has equal or more negatrive voltage than the anode pin of the reference (Pin 2).

Yes, i found that out earlier.
I currently have positive heater (pin 3) connected to 0V and negative heater (pin 4) to -15V.




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