  Gotthard-II is a silicon microstrip detector developed for the European X-ray
Free-Electron Laser (XFEL.EU). Its potential scientific applications include
X-ray absorption/emission spectroscopy, hard X-ray high resolution single-shot
spectrometry (HiREX), energy dispersive experiments at 4.5 MHz frame rate, beam
diagnostics, as well as veto signal generation for pixel detectors. Gotthard-II
uses a silicon microstrip sensor with a pitch of 50 $\mu$m or 25 $\mu$m and
with 1280 or 2560 channels wire-bonded to readout chips (ROCs). In the ROC, an
adaptive gain switching pre-amplifier (PRE), a fully differential
Correlated-Double-Sampling (CDS) stage, an Analog-to-Digital Converter (ADC) as
well as a Static Random-Access Memory (SRAM) capable of storing all the 2700
images in an XFEL.EU bunch train will be implemented. Several prototypes with
different designs of the analogue front-end (PRE and CDS) and ADC test
structures have been fabricated in UMC-110 nm CMOS technology and their
performance has been evaluated. In this paper, the performance of the analogue
front-end and ADC will be summarized.
