All ATWD inputs are preceded by a clamping amplifier which prevents the
delivery of signals beyond the input range of the ATWD.
ATWD Channel 0, the most sensitive input, has a non-clamping
amplifier in front of the clamping amplifier. When driven very
hard, the first stage saturates, causing the clamping amplifier to be
driven to its upper limit in a way that the other two amplifiers are
not.
ATWD Ch 0
input vs ATWD Ch1 input
ATWD Ch 0
input vs ATWD Ch2 input
The 0.7V undershoot of ATWD ch 0, when the input is heavily overdriven,
decays away in approximately 2 μs. This behavior may
require mitigation.
G. Przybylski, Lawrence Berkeley National Laboratory, for IceCube
