PARAMETER DEFINITIONS
TEMPERATURE COEFFICIENT
Temperature coefficient is defined as the change in output
voltage with respect to operating temperature changes, and is
normalized by an output voltage of 25°C. This parameter is
expressed in ppm/°C, and is determined by the following
equation:
TCVO
⎡
⎢⎣
ppm ⎤
°C ⎥⎦
=
VO (T2 ) − VO (T1)
VO (25°C)× (T2 − T1)
× 106
(1)
where:
VO(25°C) = VO at 25°C.
VO(T1) = VO at Temperature 1.
VO(T2) = VO at Temperature 2.
ADR520/ADR525/ADR530/ADR540/ADR550
THERMAL HYSTERESIS
Thermal hysteresis is defined as the change in output voltage
after the device is cycled through temperatures ranging from
+25°C to –40°C, then to +85°C, and back to +25°C. The
following equation expresses a typical value from a sample of
parts put through such a cycle:
VO _ HYS = VO (25°C) −VO _TC
VO _ HYS [ppm] =
VO (25°C) −VO _TC
VO (25°C)
×106
(2)
where:
VO(25°C) = VO at 25°C.
VO_TC = VO at 25°C after a temperature cycle from +25°C to
–40°C, then to +85°C, and back to +25°C.
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