Datasheet

ADR391/ADR392/ADR395
Rev. H | Page 13 of 20
TERMINOLOGY
Temperature Coefficient
The change of output voltage with respect to operating temperature
changes normalized by the output voltage at 25°C. This parameter
is expressed in ppm/°C and can be determined by
[]
() ()
() ()
6
10
–C25
–
Cppm/ ×
×°
=°
12
O
1
O
2
O
O
TTV
TVTV
TCV (1)
where:
V
O
(25°C) is V
O
at 25°C.
V
O
(T
1
) is V
O
at Temperature 1.
V
O
(T
2
) is V
O
at Temperature 2.
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 1000 hours at 25°C.
Δ
V
O
= V
O
(t
0
) − V
O
(t
1
)
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛
×
−
=Δ
6
10
)(
)()(
]ppm[
0
O
1
O
0
O
O
tV
tVtV
V
(2)
where:
V
O
(t
0
) is V
O
at 25°C at Time 0.
V
O
(t
1
) is V
O
at 25°C after 1000 hours operation at 25°C.
Thermally Induced Output Voltage Hysteresis
The change of output voltage after the device cycles through
the temperatures 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.
V
O_HYS
= V
O
(25°C) − V
O_TC
(3)
6
_
_
10
)25(
)25(
]ppm[ ×
−
=
CV
VCV
V
O
TCO
O
HYSO
o
o
(4)
where:
V
O
(25°C) is V
O
at 25°C.
V
O_TC
is V
O
at 25°C after a temperature cycle from +25°C to
−40°C to +125°C and back to +25°C.