With present-day detectors in high energy physics one is often faced with fast analog pulses of a few nanoseconds length which cover large dynamic ranges. In many experiments both amplitude and timing information have to be measured with high accuracy. Additionally, the data rate per readout channel can reach several MHz, which leads to high demands on the separation of pile-up pulses. For such applications we have designed the GANDALF transient recorder with a resolution of 12bit@1GS/s and an analog bandwidth of 500 MHz. Signals are digitized with high precision and processed by fast algorithms to extract pulse arrival times and amplitudes in real-time and to generate experiment trigger signals. With up to 16 analog channels, deep memories and a high data rate interface, this 6U-VME64x/VXS module is not only a dead-time free digitization unit but also has huge numerical capabilities provided by the implementation of a Virtex5-SXT FPGA. Fast algorithms implemented in the FPGA may be used to disentangle possible pile-up pulses and determine timing information from sampled pulse shapes with a time resolution in the picosecond range.

Recently the application spectrum has been extended by designing a digital input mezzanine card with 64 differential inputs. This design option provides up to 128 digital inputs per GANDALF module and allows for the implementation of TDCs, scalers, mean-timers and logic functions within the FPGA.