ad1582crt-reel7 Analog Devices, Inc., ad1582crt-reel7 Datasheet - Page 13

• Manufacturer Part Number: ad1582crt-reel7
• Description: 2.5 V To 5.0 V Micropower, Precision Series Mode Voltage References
• Manufacturer: Analog Devices, Inc.

NOISE PERFORMANCE AND REDUCTION
The noise generated by the AD1582/AD1583/AD1584/AD1585 is
typically less than 70 μV p-p over the 0.1 Hz to 10 Hz frequency
band. Figure 19 shows the 0.1 Hz to 10 Hz noise of a typical
AD1582/AD1583/AD1584/AD1585. The noise measurement
is made with a high gain band-pass filter. Noise in a 10 Hz to
10 kHz region is approximately 50 μV rms. Figure 20 shows the
broadband noise of a typical AD1582/AD1583/AD1584/AD1585.
If further noise reduction is desired, add a 1-pole, low-pass
filter between the output pin and ground. A time constant of
0.2 ms has a −3 dB point at roughly 800 Hz and reduces the
high frequency noise to about 16 V rms. It should be noted,
however, that while additional filtering on the output can
improve the noise performance of the AD1582/AD1583/
AD1584/AD1585, the added output impedance can degrade
the ac performance of the references.
100
90
80
70
60
50
40
30
20
10
100
0%
10
0
90
1
Figure 19. 10 Hz to 10 kHz Wideband Noise
Figure 18. Ripple Rejection vs. Frequency
10µV
10
100
FREQUENCY (Hz)
1k
AD1585
AD1582
10k
1s
100k
1M
Rev. H | Page 13 of 16
TURN-ON TIME
Many low power instrument manufacturers are concerned
with the turn-on characteristics of the components used in their
systems. Fast turn-on components often enable the end user to
save power by keeping power off when not needed. Turn-on
settling time is defined as the time required, after the application of
power (cold start), for the output voltage to reach its final value
within a specified error. The two major factors affecting this are
the active circuit settling time and the time required for the
thermal gradients on the chip to stabilize. Figure 21 shows the
turn-on settling and transient response test circuit. Figure 22
shows the turn-on characteristics of the AD1582/AD1583/
AD1584/AD1585. These characteristics are generated from cold-
start operation and represent the true turn-on waveform after
power-up. Figure 23 shows the fine settling characteristics of
the AD1582/AD1583/AD1584/AD1585. Typically, the reference
settles to within 0.1% of its final value in about 100 μs.
The device can momentarily draw excessive supply current
when V
Power supply resistance must be low enough to ensure reliable
turn-on. Fast power supply edges minimize this effect.
0V OR 10V
0V TO 10V
100
SUPPLY
0%
90
10
Figure 21. Turn-On/Transient Response Test Circuit
AD1582/AD1583/AD1584/AD1585
is slightly below the minimum specified level.
10kΩ
10kΩ
100µV
Figure 20. 1 Hz to 10 Hz Voltage Noise
0.22µF
DUT
10ms
V
OUT
0.22µF
5V OR 10V
0V OR 5V