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VREF-399 Spec Sheet

VREF-399 Precision Voltage Reference Features

    LM399 heater stabilized buried zener design
    Excellent short and long term stability
    Completely linear, no switching noise
    Six floating outputs in 1 volt increments
    All outputs buffered with low noise op amps
    Easy to use banana jacks
    Great for lab applications
    Perfect for calibrating 24 bit A/D's
    Use with potentiometers and voltage dividers
    Price $200 for bundled "in the box" system
    Spec Table
    PDF Documents & Software
VREF-399 -- click for tour

Download PDF Product Flyer PDF icon , User Manual PDF icon

Product Description

The Symmetric Research VREF-399 is a precision voltage reference suitable for general lab use and for applications such as the calibration of high resolution A/D converters. The reference provides excellent long term voltage stability with the same voltages returned from one power on cycle to the next.

The voltage reference as a whole is floating. Any one of the outputs may be taken as ground, with the other outputs then distributed positive or negative from the grounded output. This results in a very flexible test instrument which can be used in a variety of applications.

Voltages are available on individual banana jacks, with each of the six jacks approximately one volt apart. A calibration tag with the voltages as measured at the time of production is included with each system. There are no trim pots to be adjusted, all voltages are permanently fixed.

The system is easy to use, requiring only power and connections to the reference banana jacks. A PDF User manual, desktop enclosure, power supply, banana plugs, and alligator cables are included with the "in the box" system.

Specifications Table

For more detailed specifications, please see the User Manual.

VREF-399 Specs
Outputs: 6 floating outputs in 1 volt increments  
Output Range: -5v to +5v depending on ground location  
Short term output noise: 5 microvolts peak to peak  
Thermal stability: Max 2 ppm per degree C, typical 0.3 ppm  
Voltage Reference: Heated buried zener,  NSC LM399,   AN161  
Output Buffering: Op amp, low noise,  TI OPA2277  
Power Supply Voltage: Min 14.7, typical 17, max 30 vdc FAQ note 
Power Supply Current: Operating 60 mA, warmup max 200 mA  
Board Dimension: 2.50" W x 5.00" D  
Enclosure Dimension: 2.50" W x 5.00" D x 1.25" H  
ROHS Compliance: Compilant by exemption  FAQ note 
Price: See "in the box" table below  

Documents PDF icon and Software

These documents represent the complete specs for this product. They can also be found on our Downloads page.

VREF-399 Documents & Software
Category Description Rev File # bytes
Product Flyer VREF-399 specs 2012/01/01 flyvref399.pdf 103,175
User Manual VREF-399 user manual 2010/01/15 manvref399.pdf 678,437

Price Table

The following items may be purchased individually or at a discount as a bundled "in the box" system. When purchasing a VREF-399 "in the box" system, the following are included:

VREF-399 In The Box
Item Description Price
WITHCASE-VREF-399 Precision voltage reference with 6 outputs and case $175
CABLE-VREF399-BANANA6 Six stainless steel banana plugs with solder lugs $14
CABLE-VREF399-ANALOGOUT Three 12" banana plug to alligator cables (24 gauge wire) $20
12 vdc, 500 ma wall transformer, 110 vac input
(or substitute a 220 vac euro transformer on request)
CD-VREF-399 CD with PDF user manual $1
  Individual item subtotal = $220
  "In the box" discount ( box contents photo ) - $20
VREF-399 Final price (how to order) = $200


Some users may want to consider these additional options:

VREF-399 Options
Item Description Price
CABLE-VREF399-ANALOGOUT Three more banana plug to alligator cables beyond those already "in the box" $20
SUB-TRANS-EURO-12V-DC Substitute a 220 vac Euro style wall transformer $0 Copyright © Symmetric Research