Typical Application Circuits

(Continued)

how to use two resistors to level shift V

reference voltage of V

at V

V

Conversely, the R2 resistor can be placed between V

SENSE

and V

reference voltage of V

the resistors can be seen below:

V

Reference Voltage

DDR-SDRAM and the motherboard chipsets usually require

a reference voltage which tracks V

feature in most applications it is advisable to use two equal

resistors as a resistor divider. This prevents long V

from running across the motherboard picking up noise which

can interfere with performance. However, in a few applica-

tions it may be desirable to use the V

LP2994 to generate the V

plished by using an RC filter on the output of V

V

chipsets and memory is well under 1µA combined, therefore,

a fairly large resistor such as 1k

Ω or larger can be used. A

recommended capacitor would be a 1uF X7R ceramic

capacitor.

20045909

FIGURE 9. Increasing V

20045910

FIGURE 10. Decreasing V

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