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User's Manual (MUT)
Mod. V1729 4 Channel 12 Bit Sampling ADC
22/06/2005
3
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00109/04:V1729.MUTx/03 V1729_REV3.DOC
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4. Technical specifications
4.1
Packaging
The Model V1729 is housed in a one unit standard VME unit.
4.2 Sampling
frequency
The V1729 board is sequenced by an oscillator at Fp frequency. No greater frequency
signal exists on the board. This is what explains the low consumption of the system. The
sampling at a very high frequency (Fe) in the MATACQ chip is in fact realized by virtual
multiplication of frequency inside the chip by a factor up to 20.
The MATACQ chip functions with Fp = 50MHz or 100MHz programmable on the board
by software, which corresponds to a sampling frequency Fe (= 20*Fp) of 1 or 2 GHz.
4.3 Input signals, Dynamic range
The V1729 board integrates 4 analog channels. The inputs of these channels are
connected through double LEMO plugs (IN0+/- à IN3+/-).
The inputs are by default unipolar and terminated on 50 Ohms. However, the input levels
of the board can be very easily modified (through displacing a few resistors and mounting
new ones) in such a way as to permit the input in differential mode (from which the
double LEMO plugs). For this purpose, free CMS-805 resistor footprints are indeed
implemented on the V1729 board (see IV.1.g).
The analog to digital conversion is made on 12 bits with a maximum dynamic range of
1V, or an LSB of 250µV. This range is centered on 0V (+/- 0.5V).
The measured noise referred to input is less than 200 µV RMS (i-e below the lsb of the
ADC), and the non-linearity remains below 1 per 1000 over the whole dynamic range.