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LT1027 based 5V Voltage Reference

For comparing my Voltmeters and because of deep interest I build a LT1027 based 5V Reference Voltage Source.

LT1027 Schematic
Schematic

I build it Bird Nest style ( hope this is the right expression) on a single side Copper Board.

The low noise Voltage regulator (LT1763) is mounted on a daughter board.

LT1763 Board_web
Daughter board with Voltage Regulator.

 

Ref in Geh_web
First test if it fits in the housing.

 

Final build but some decoupling capacitors and the input protection diodes still missing.

Ref 1027 Final_web
Final Build

The finished Refernze in Housing.

Referenz Zu_web
Reference in Housing-

First measurements with my 4,5 digit handheld multimeter shows 4.997V

After 30 days of continous running the measurement with a new calibrated 6,5 digit voltmeter shows between 5,00096 and 5,00097V.

The oszilloscope pictures shows the difference between batterie and power supply operation.
No Filter!

All measurements are done with a 1:1 probe with the following settings:
1mV/Div und 2mS/DIV

 

GND Taste
GND Button pushed.

 

LT1027 15V NT
Reference operated with a linear LM7815 based power supply. Not floating!!

 

LT 1027 2 x 9V Block
Reference powered with  9V Block batteries.

I have build a 15V power supply with an electronic ripple rejection(it is from an German Electronic Forum) followed by an LM7815.

Now floating!!

The result is a line similar to the picture with the batterie operation. No ripple. The line is twice as thick ( hope this is the right expression)

Oscilloscope picture follows…

Links:
Rippel rejection   German article in ELKO Forum
LT1027 Kondensator Noise Reduktion  German thread in Mikrocontroller Forum

Thanks to all supporting thread members.

UPDATE 09.02.2014

I put the whole circuit into styrofoam insulated Box and put a PTC-heater foil under the Metal case.

Pack

The Pack.

 

Heater

This is the PTC-heater Foil,  12Volt 3Watts. The heater is only controled with it built in PTC. I used a 12 V Switching Power supply for the heater and a linera voltage source for my reference.

 

Here some measurements at different temperatures:

Voltage Temperaturet

My thermometer is not calibrated it started at 9° Celsius which is equal to the ambient temperature of 15°Celsius. Hope to get a better one the next days…

Will be continued…

 

 

 

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