Datasheet

J A D JA
T T P R
T
 
6
OUTMAX OUTMIN
OUT
V V
Drift 10 (ppm)
V Temperature Range
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-
= ×
ç ÷
×
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REF3312 , REF3318 , REF3320 , REF3325 , REF3330 , REF3333
www.ti.com SBOS392D –AUGUST 2007–REVISED JUNE 2014
Feature Description (continued)
9.3.2 Low Temperature Drift
The REF33xx is designed for minimal drift error, defined as the change in output voltage over temperature. The
drift is calculated using the box method, as described in Equation 2:
(2)
9.3.3 Power Dissipation
The REF33xx family is specified to deliver current loads of ±5 mA over the specified input voltage range. The
temperature of the device increases according to Equation 3:
where
• T
J
= junction temperature (°C).
• T
A
= ambient temperature (°C).
• P
D
= power dissipation (W) = V
IN
× I
Q
+ (V
IN
– V
OUT
) I
OUT
.
• R
θJA
= Junction-to-ambient thermal resistance (°C/W). (3)
The REF33xx junction temperature must not exceed the absolute maximum rating of 150°C.
9.3.4 Noise Performance
Typical 0.1-Hz to 10-Hz voltage noise for each member of the REF33xx family is specified in the Electrical
Characteristics table. The noise voltage increases with output voltage and operating temperature. Use additional
filtering to improve output noise levels. Give special attention to ensure that the output impedance does not
degrade output voltage accuracy.
9.4 Device Functional Modes
The REF33xx is powered on when the voltage on the IN pin is greater than V
OUT
+ 0.2 V, except for the
REF3312, where the minimum supply voltage is 1.8 V. The maximum input voltage for the REF33xx is 5.5 V.
Use a supply bypass capacitor ranging between 1 μF to 10 μF. The total capacitive load at the output must be
between 0.1 μF to 10 μF to ensure output stability.
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Product Folder Links: REF3312 REF3318 REF3320 REF3325 REF3330 REF3333