Threshold Scans

A threshold scan for different bias voltages was performed. The detector boards 4 and 2 were the devices under test (DUT).
The order of the detector planes was the following:

Ordering of detector planes. Beam plane 1 is the most upstream one.
beam plane	detector board #	dsp dac channel	dsp dac voltage
1	3	5	120 mV (x78)
2	4	4	DUT
3	0	3	80 mV (x50)
4	1	2	120 mV (x78)
5	5	1	120 mV (x78)
6	2	0	DUT

The threshold of the detector planes 0, 1, 3 and 5 were fixed.

Threshold scan: dac values in mV (hex value) set from the dsp. This value is different from the value at the detector board
run#	V_bias	dac value channel 0	dac value channel 4

407	140	120 mV (x78)	120 mV (x78)
408	190
409	100
410	60
411	25
412	25	240 mV (xf0)	240 mV (xf0)
413	60
414	100
415	190
416	190	600 mV (x258)	600 mV (x258)
417	140
418	100
419	100	180 mV (xb4)	180 mV (xb4)
420	60	180 mV (xb4)	180 mV (xb4)
421	25
422	25	96 mV (x60)	96 mV (x60)
423	25	108 mV (x6c)	108 mV (x6c)
424	25	96 mV (x60)	96 mV (x60)
425	60	144 mV (x90)	144 mV (x90)
426	100	300 mV (x12c)	300 mV (x12c)
427	190
428	190	360 mV (x168)	360 mV (x168)
429	100
430	100	204 mv (xcc)	204 mV (xcc)
431	60
432	190	480 mV (x1e0)	480 mV (x1e0)
433	190	264 mV (x108)	264 mV (x108)
434	100
435	60

Noise Scan

The occupancy was measured for different thresholds. The bias voltage was fixed to 140V.
The threshold voltages are those set at the dsp-dac. They differ from the actual voltages at
the detector boards.

Noise Scan. Threshold voltage set at the dsp.
Threshold [mV]	Run #
20	505
30	506
40	507
50	508
60	511
70	509
80	512
90	510
100	513
120	514
150	515

This page was last modified Nov 13-97 by Wilko