6.1.2ADC
1.Successive approximation ADC with sliding scale linearisation
●Channel splitting 128, 256, 512, 1K, 2K, or 4K
●Full input voltage range 3V, positive and negative (10V with external attenuator)
2.ADC Dead time (including time needed to write into memory)
●< 8 µsec
3.Nonlinearities
●Differential nonlinearity (over 95% channel range) <2%
●Integral nonlinearity (over 95% channel range) <0.1%
4.Peak capturing
●Works with pulse of gaussian shaping amplifier (range of shaping time constant between 0.5µs and 5µs)
5.Temperature Stability
●TK 100 (ADC), TK 500 (Amplifier)
6.Discriminators and threshold
●Digital LLD and ULD (allows channelwise cutting)
●Analogue threshold (2...60% of ADC range)
●Multi Channel Scaling (MCS) mode allowing to count the following pulses
●TTL input pulses (minimum width of flat top 0.2µs) not routed through the ADC (maximum rate 1 MHz)
●LLD/ULD counting mode, counting pulses within a preset digital window
●Count rate derived from internal amplifier ICR signal (maximum count rate determined by count rate limitation of amplifier )
●Dwell time 0.01s to 500s
7.Spectrometric performance:
●Resolution (FWHM) for typical 500mm² planar HPGe detector for count rates < 10000cps and a
●610±20eV at 1µs shaping time
●580±20eV at 2µs shaping time
●Peak shift:
< 0.5% for 1µs shaping time and count rates from 1000 to 70000cps
< 0.2% for 2µs shaping time and count rates from 1000 to 40000cps
●deterioration of FWHM < 5% for both conditions
●Throughput in memory:
at least 25000cps in memory at 50000cps input rate and 1µs shaping time
at least 13000cps in memory at 30000cps input rate and 2µs shaping time
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