Pulse shape space of Helix128 for Vfp=-0.25V

The pictures in the table below give a pulse shape scan at various bias settings and load capacitances. The x-Axis is time in ns. The various curves show the shape for different external load capacitances, i. e. detector capacitances for two Helix chips. The capacitances are 1.6pF, 6.8pF, 16.3pF, 29.4pF and 58pF. The 29.4pF curve was measured twice (hence, since there are two chips measured, there are 4 curves for this value). Higher capacitive load yields lower gain.

The relation between the curve labeled "Reihe 1" ... "Reihe 12" is given in the following table:
Reihe 1 29.4pF
Reihe 2 29.4pF
Reihe 3 0pF
Reihe 4 0pF
Reihe 5 6.8pF
Reihe 6 6.8pF
Reihe 7 29.4pF
Reihe 8 29.4pF
Reihe 9 16.3pF
Reihe 10 16.3pF
Reihe 11 58pF
Reihe 12 58pF

The y-Axis is the measured amplitude in V with an analogue receiver circuit as described in the Helix128-x User manual at the section "The analog receiver circuit" with a feedback resistance of 300Ohms.

The preview links to a Postscript file containing the plot. The text header in each table cell links to an ASCII data file which contains the pulse shape data. Data in this file is organized in columns. The first column contains the time, the other columns contain the pulse shape amplitude.
 
Ipre=100uA
Vfs=0.0V
Vfp=-0.25V, Vfs=0.0V, Ipre=100uA

Vfp=-0.25V, Vfs=0.0V, Ipre=100uA
Vfs=0.5V
Vfp=-0.25V, Vfs=0.5V, Ipre=100uA

Vfp=-0.25V, Vfs=0.5V, Ipre=100uA
Vfs=1.0V
Vfp=-0.25V, Vfs=1.0V, Ipre=100uA

Vfp=-0.25V, Vfs=1.0V, Ipre=100uA
Vfs=1.5V
Vfp=-0.25V, Vfs=1.5V, Ipre=100uA

Vfp=-0.25V, Vfs=1.5V, Ipre=100uA
Vfs=2.0V
Vfp=-0.25V, Vfs=2.0V, Ipre=100uA

Vfp=-0.25V, Vfs=2.0V, Ipre=100uA

Last changes: 99/11/12 by Martin Feuerstack-Raible

If you have comments or suggestions, email Ulrich Trunk