  Application Specific Integrated Circuits, ASICs, similar to those envisaged
for the readout electronics of the central calorimeters of detectors for a
future lepton collider have been exposed to high-energy electromagnetic
showers. A salient feature of these calorimeters is that the readout
electronics will be embedded into the calorimeter layers. In this article it is
shown that interactions of shower particles in the volume of the readout
electronics do not alter the noise pattern of the ASICs. No signal at or above
the MIP level has been observed during the exposure. The upper limit at the 95%
confidence level on the frequency of faked signals is smaller than 1x10^{-5}
for a noise threshold of about 60% of a MIP. For ASICs with similar design to
those which were tested, it can thus be largely excluded that the embedding of
the electronics into the calorimeter layers compromises the performance of the
calorimeters.
