ADR02 AD [Analog Devices], ADR02 Datasheet - Page 9

• Manufacturer Part Number: ADR02
• Description: Ultracompact Precision10 V/5 V/2.5 V/3.0 V Voltage References
• Manufacturer: AD [Analog Devices]

PARAMETER DEFINITIONS
Temperature Coefficient
The change of output voltage with respect to operating tem-
perature changes normalized by the output voltage at 25°C. This
parameter is expressed in ppm/°C and can be determined by the
following equation:
where:
V
V
V
Line Regulation
The change in output voltage due to a specified change in input
voltage. This parameter accounts for the effects of self-heating.
Line regulation is expressed in either percent per volt, parts-
per-million per volt, or microvolts per volt change in input
voltage.
Load Regulation
The change in output voltage due to a specified change in load
current. This parameter accounts for the effects of self-heating.
Load regulation is expressed in either microvolts per milliampere,
parts-per-million per milliampere, or ohms of dc output
resistance.
Long-Term Stability
Typical shift of output voltage at 25°C on a sample of parts
subjected to a test of 1,000 hours at 25°C:
where:
V
V
The majority of the shift is seen in the first 200 hours, and,
as time goes by, the drift decreases significantly. So for the
subsequent 1,000 hours’ time points, this drift is much smaller
than the first.
O
O
O
O
O
(25°C) = V
(T
(T
(t
(t
0
1
TCV
1
2
) = V
) = V
∆
∆
) = V
) = V
V
V
O
O
O
[
=
O
O
ppm
[
O
O
V
at 25°C at Time 0
at 25°C after 100 hours of operation at 25°C
ppm
at Temperature 1
at Temperature 2
O
O
(
]
at 25°C
t
0
=
/
°
)
V
C
−
O
]
V
(
=
O
t
V
0
(
V
O
t
)
V
1
O
−
(
)
O
t
(
V
0
25
(
O
)
T
2
°
(
C
t
)
1
−
)
)
×
V
×
O
T
10
2
(
T
6
−
1
T
)
1
×
10
6
Rev. F | Page 9 of 20
Thermal Hysteresis
Defined as the change of output voltage after the device is
cycled through temperature from +25°C to –40°C to +125°C
and back to +25°C. This is a typical value from a sample of parts
put through such a cycle.
where:
V
V
+125°C and back to +25°C
NOTES
Input Capacitor
Input capacitors are not required on the ADR01/ADR02/
ADR03/ADR06. There is no limit for the value of the capacitor
used on the input, but a 1 µF to 10 µF capacitor on the input
improves transient response in applications where the supply
suddenly changes. An additional 0.1 µF in parallel also helps to
reduce noise from the supply.
Output Capacitor
The ADR01/ADR02/ADR03/ADR06 do not require output
capacitors for stability under any load condition. An output
capacitor, typically 0.1 µF, filters out any low level noise voltage
and does not affect the operation of the part. On the other hand,
the load transient response can be improved with an additional
1 µF to 10 µF output capacitor in parallel. A capacitor here acts
as a source of stored energy for a sudden increase in load
current. The only parameter that degrades by adding an output
capacitor is the turn-on time, and it depends on the size of the
capacitor chosen.
O
O_TC
(25°C) = V
V
V
= V
O
O
_
_
HYS
HYS
O
at 25°C after temperature cycle at +25°C to –40°C to
[
O
=
ppm
at 25°C
V
ADR01/ADR02/ADR03/ADR06
O
]
(
25
=
V
°
C
O
)
(
25
V
−
O
V
°
O
C
(
25
_
)
TC
−
°
C
V
O
)
_
TC
×
10
6