Hi Mitch,
Congrats! Very encouraging preliminary results.
Thanks to all,
Fernando
Mitch Newcomer wrote:
To All,
Looks like a very successful (Amplifier Shaper) prototype !
We measured the epected 35mW per channel power dissipation. Shape
looks good ( nothing but a paper printer on the scope) Here are the
first measurements with all default switch settings: We used an old
Lecroy Scope for the pulse measurements and found some variation in
measurement repeatability so some of the variation in the table may
simply be hookup or scope related.
The output of the chip is a current and has been modeled with a 62ohm
per side load. The scope measurements were made using a MiniCircuit
T1-1 transformer between the outputs with the other side connected to a
50 ohm terminated cable. This presents a load to the A and B outputs
of 25 ohms each to virtual ground, so the raw data below is in the
column labeled 25 ohms, and we simply scaled to get the expected
differential voltage across the intended 62 ohm load resistors.
-Mitch ( with significant help from Godwin Mayers who wired up the
test socket and a talented summer student, Kurt Brendlinger from Yale.)
Preliminary Pulse Measurements on the GAS-1 Chip:
Ain --> negative impulse input
Bin --> positive impulse input
| 11-Jul-07 |
|
32fC impulse
input |
|
|
|
25Ω imp |
62Ω imp |
|
| Input |
∆T (ns) |
∆V (mV) |
|
62Ω Gain |
| AIN_1 |
7.7 |
43.6 |
108.128 |
3.379 |
| BIN_1 |
8 |
41 |
101.68 |
3.1775 |
| AIN_2 |
7.6 |
42 |
104.16 |
3.255 |
| BIN_2 |
7.8 |
40.5 |
100.44 |
3.13875 |
| AIN_3 |
7.7 |
41 |
101.68 |
3.1775 |
| BIN_3 |
8 |
39.2 |
97.216 |
3.038 |
| AIN_4 |
7.9 |
41 |
101.68 |
3.1775 |
| BIN_4 |
8 |
38 |
94.24 |
2.945 |
| AIN_5 |
7.8 |
39.7 |
98.456 |
3.07675 |
| BIN_5 |
8 |
37.6 |
93.248 |
2.914 |
| AIN_6 |
7.5 |
39.8 |
98.704 |
3.0845 |
| BIN_6 |
8 |
35 |
86.8 |
2.7125 |
| AIN_7 |
7.6 |
36 |
89.28 |
2.79 |
| BIN_7 |
7.6 |
37 |
91.76 |
2.8675 |
| AIN_8 |
7.8 |
40 |
99.2 |
3.1 |
| BIN_8 |
8 |
39.3 |
97.464 |
3.04575 |
|