5962-8982502PA Datasheet, PDF (7/12 Pages) Analog Devices – High Precision 10 V Reference

TURN-ON TIME
Upon application of power (cold start), the time required for
the output voltage to reach its final value within a specified
error band is defined as the turn-on settling time. Two compo-
nents normally associated with this are the time for the active
circuits to settle and the time for the thermal gradients on the
chip to stabilize. Figure 7, Figure 8, and Figure 9 show the turn-
on characteristics of the AD587. These figures show the settling
to be about 60 μs to 0.01%. Note the absence of any thermal tails
when the horizontal scale is expanded to 1 ms/cm in Figure 8.
Output turn-on time is modified when an external noise reduc-
tion capacitor is used. When present, this capacitor acts as an
additional load to the current source of the internal Zener
diode, resulting in a somewhat longer turn-on time. In the case
of a 1 μF capacitor, the initial turn-on time is approximately
400 ms to 0.01%, as shown in Figure 9.
10V
+V_IN
100
90
1mV
V_OUT
10
0%
20µs
Figure 7. Electrical Turn-On
20V
10V
+V_{IN 100}
90
V_OUT
1ms
10
0%
Figure 8. Extended Time Scale
10V
1V
+V_IN
100
90
AD587
100ms
V_OUT
10
0%
Figure 9. Turn-On with 1 μF CN
DYNAMIC PERFORMANCE
The output buffer amplifier is designed to provide the AD587
with static and dynamic load regulation that is superior to less
complete references.
Many ADCs and DACs present transient current loads to the
reference, and poor reference response can degrade the con-
verter’s performance.
Figure 11 and Figure 12 display the characteristics of the AD587
output amplifier driving a 0 mA to 10 mA load.
7.0V
V_OUT
1kΩ
V_L
AD587
10V
0V
Figure 10. Transient Load Test Circuit
10V
50mV
1µs
V_L 100
90
V_OUT
10
0%
Figure 11. Large-Scale Transient Response
Rev. H | Page 7 of 12