Q
Q1. Does it matter if the supply rails do not rise in voltage together
at power-up?
Q2. Similarly does it matter if the supply rails do not fall in voltage
together at power-down?
Q3. Will the AD667 tolerate one or more of the supply rails stuck at
zero volts?
Q4 If so, for how long?
A
Q1. Does it matter if the supply rails do not rise in voltage together
at power-up?
The AD667 is power cycle tested and will tolerate different rise times on VCC
and VEE. The part will not operate to specification until the supplies are at
least ?12V. Once the supplies have reached their final value the part will
operate to spec. A difference in the rise time of the supplies will not cause
damage to the AD667. Where you do need to take care is to ensure that at no
time during the power up or power down of the device should the voltage present
at any of the digital inputs be higher than VCC or lower than VEE.
Q2. Similarly does it matter if the supply rails do not fall in voltage
together at power-down?
Same answer as above. Any difference in the fall time of the supplies will
cause any damage to the AD667.
Q3. Will the AD667 tolerate one or more of the supply rails stuck at
zero volts?
Yes. The part will not be damaged by holding one of the supplies at 0V (unless
the any of the digital inputs exceed the supplies). The AD667 will not operate
to spec when in this condition.
Q4 If so, for how long?
Indefinite. The part will recover correct operation once the supplies are
brought into spec.
