2.1 Heritage
13
Table 2.1 Summary of tested specifications for the PASA [1]
Parameter
Tested value
Voltage supply
3.3 V
Technology
AMS 0.35 µm
Channels per chip
16
Polarity
Positive
Detector capacitance (C d )
12.5 pF
Peaking time (t s )
190 ns
Noise (ENC)
385 e @ 12 pF
Sensitivity (gain)
12.8 mV/fC @ 12 pF
Non-Linearity
0.2%
Crosstalk
<0.1%
Power consumption (per ch)
11.67 mW
Die size
18 mm 2
Fig. 2.1 A simplified block diagram of the PASA signal processing chain [1]
2.1.2 ALTRO/S-ALTRO
The ALTRO chip [2–4, 12] is a mixed signal analogue-digital integrated circuit dedicated to the digitization and processing of gaseous detector signals. It was originally
designed for use in the ALICE TPC detector, though it has also been used in other
detectors. The ADC used for the ALTRO is a commercial pipelined ADC provided by
ST Microelectronics, while the S-ALTRO uses a custom designed pipelined ADC [9].
13
Table 2.1 Summary of tested specifications for the PASA [1]
Parameter
Tested value
Voltage supply
3.3 V
Technology
AMS 0.35 µm
Channels per chip
16
Polarity
Positive
Detector capacitance (C d )
12.5 pF
Peaking time (t s )
190 ns
Noise (ENC)
385 e @ 12 pF
Sensitivity (gain)
12.8 mV/fC @ 12 pF
Non-Linearity
0.2%
Crosstalk
<0.1%
Power consumption (per ch)
11.67 mW
Die size
18 mm 2
Fig. 2.1 A simplified block diagram of the PASA signal processing chain [1]
2.1.2 ALTRO/S-ALTRO
The ALTRO chip [2–4, 12] is a mixed signal analogue-digital integrated circuit dedicated to the digitization and processing of gaseous detector signals. It was originally
designed for use in the ALICE TPC detector, though it has also been used in other
detectors. The ADC used for the ALTRO is a commercial pipelined ADC provided by
ST Microelectronics, while the S-ALTRO uses a custom designed pipelined ADC [9].