Datasheet
DocID023274 Rev 4 17/28
TSX56x, TSX56xA Application information
28
Equation 5
To evaluate the op-amp reliability, a follower stress condition is used where V
CC
is defined
as a function of the maximum operating voltage and the absolute maximum rating (as
recommended by JEDEC rules).
The V
io
drift (in µV) of the product after 1000 h of stress is tracked with parameters at
different measurement conditions (see
Equation 6).
Equation 6
The long term drift parameter (ΔV
io
), estimating the reliability performance of the product, is
obtained using the ratio of the V
io
(input offset voltage value) drift over the square root of the
calculated number of months (
Equation 7).
Equation 7
where V
io
drift is the measured drift value in the specified test conditions after 1000 h stress
duration.
4.5 PCB layouts
For correct operation, it is advised to add 10 nF decoupling capacitors as close as possible
to the power supply pins.
4.6 Macromodel
Accurate macromodels of the TSX56x, TSX56xA devices are available on the
STMicroelectronics’ website at www.st.com. These models are a trade-off between
accuracy and complexity (that is, time simulation) of the TSX56x and TSX56xA operational
amplifiers. They emulate the nominal performance of a typical device within the specified
operating conditions mentioned in the datasheet. They also help to validate a design
approach and to select the right operational amplifier, but they do not replace on-board
measurements.
Months A
F
1000 h× 12 months 24 h 365.25 days×()⁄×=
V
CC
maxV
op
with V
icm
V
CC
2⁄==
ΔV
io
V
io
drift
months()
------------------------------=