Agilent Technologies E1439 User Manual page 154

Agilent E1439 Programmer's Reference
Functions listed alphabetically
Comments
To ensure full alias-free operation the analog anti-alias filter should be ON unless the application
inherently bandlimits the input signal to less than fs/2. The analog anti-alias filter has a fixed
bandwidth and thus is fully effective only when fs ≥ 100 MHz. If a slower external ADC clock is
used, an additional analog filter of the appropriate bandwidth may be required for full alias
protection.
When using the analog anti-alias filter, you may need to set the range parameter higher than the
actual range of the input signal. The reason for this is that step changes of input voltage cause an
overshoot and ringing response at the output of the anti-alias filter. The peak overshoot actually
exceeds the input voltage step by about 20%. The range setting must accommodate this overshoot
to avoid an ADC overflow.
Return Value
AGE1439_SUCCESS indicates that a function was successful.
Values other than AGE1439_SUCCESS indicate an error condition or other important status
condition. To determine the error message, pass the return value to "age1439_error_message" on
page 102.
See Also
"age1439_init" on page 132, "age1439_input_autozero" on page 134, "age1439_input_range_
auto" on page 137, "age1439_input_range_convert" on page 138, "age1439_data_scale_get" on
page 89
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