SUPPLY CURRENT vs INPUT VOLTAGE

42.5

42.0

41.5

41.0

40.5

40.0

1

1.5

2

2.5

3

3.5

4

4.5

5

5.5

6

V

REF3033-Q1

www.ti.com

SBVS131 – JANUARY 2010

Figure 3. Supply Current vs Supply Voltage

Supply voltages below the specified levels can cause the REF30xx to momentarily draw currents greater than

the typical quiescent current. Using a power supply with a fast rising edge and low output impedance easily

prevents this.

Thermal Hysteresis

Thermal hysteresis for the REF30xx is defined as the change in output voltage after operating the device at

25°C, cycling the device through the specified temperature range, and returning to 25°C, and can be expressed

as:

Where

–40°C to 85°C, and returned to operation at 25°C.

Temperature Drift

The REF30xx is designed to exhibit minimal drift error, defined as the change in output voltage over varying

temperature. Using the "box" method of drift measurement, the REF30xx features a typical drift coefficient of

20 ppm from 0°C to 70°C—the primary temperature range of use for many applications. For automotive

temperature ranges of –40°C to 85°C, the REF30xx family drift increases to a typical value of 50 ppm.

Noise Performance

The REF30xx generates noise less than 50

μVp-p between frequencies of 0.1 Hz to 10 Hz, and can be seen in

the typical characteristic curve "0.1 to 10Hz Voltage Noise." The noise voltage of the REF30xx increases with

output voltage and operating temperature. Additional filtering may be used to improve output noise levels,

although care should be taken to ensure the output impedance does not degrade AC performance.

Long-Term Stability

Long term stability refers to the change of the output voltage of a reference over a period of months or years.

This effect lessens as time progresses as is apparent by the long term stability curves. The typical drift value for

the REF30xx is 24 ppm from 0 to 1000 hours and 15 ppm from 1000 to 2000 hours. This parameter is

characterized by measuring 30 units at regular intervals for a period of 2000 hours.

Copyright © 2010, Texas Instruments Incorporated

Submit Documentation Feedback

9

Product Folder Link(s): REF3033-Q1