Difference between revisions of "Row-specific SQ2 feedback (fast switching)"
(Created page with 'The SQ2-Feedback (SQ2FB) output of the MCE, controlled by a DAC can be set to either a constant value or a row-specific set of values switching at row-visit rate. The SQ2FB outpu…') |
(→Rev. F and later) |
||
| Line 9: | Line 9: | ||
== Rev. F and later == | == Rev. F and later == | ||
Bias Cards Rev. F and later have faster outputs and they can be switched at row-visit rate. The firmware support for switching SQ2FB values at row-visit rate is added starting revision '''5.0.5'''. | Bias Cards Rev. F and later have faster outputs and they can be switched at row-visit rate. The firmware support for switching SQ2FB values at row-visit rate is added starting revision '''5.0.5'''. | ||
| − | + | ;Relevant mce parameters | |
| − | + | :fb_col0, fb_col1, ..., fb_col31 : each specify up to 41 values, loaded in order when enbl_mux is set to 1 | |
| − | + | :enbl_mux : 0 to have constant outputs, 1 to have switching ouputs | |
| − | + | :flux_fb : | |
| − | + | :row_len : specifies output switching rate | |
| − | + | ;Software requirements | |
= Address-card-driven SQ2FB = | = Address-card-driven SQ2FB = | ||
Revision as of 18:29, 22 November 2010
The SQ2-Feedback (SQ2FB) output of the MCE, controlled by a DAC can be set to either a constant value or a row-specific set of values switching at row-visit rate. The SQ2FB output is driven by the card plugged into the BC2 slot of the MCE. Either a Bias Card or an Address Card can be plugged into the BC2 slot.
Contents
[hide]Bias-card-driven SQ2FB
Prior to Rev. F
Bias Cards earlier than Rev. F have a slow opamp at the output followed by 2 sets of kHz range RC filters that limit the output switching frequency to few kHz range and prevents the output from switching at the row-visit rate. Therefore, when these bias cards are used in BC2 slot, only a constant SQ2FB value (one value per array-column) can be specified.
- Relevant mce parameters
- flux-fb
Rev. F and later
Bias Cards Rev. F and later have faster outputs and they can be switched at row-visit rate. The firmware support for switching SQ2FB values at row-visit rate is added starting revision 5.0.5.
- Relevant mce parameters
- fb_col0, fb_col1, ..., fb_col31 : each specify up to 41 values, loaded in order when enbl_mux is set to 1
- enbl_mux : 0 to have constant outputs, 1 to have switching ouputs
- flux_fb :
- row_len : specifies output switching rate
- Software requirements
Address-card-driven SQ2FB
http://cmbr.phas.ubc.ca/mcewiki/index.php/Fast_SQ2_Feedback_and_TES_Biasing_with_an_Address_Card
- detector bias considerations
- Firmware requirement
- v5.0.0+
- Software requirement
- Edit experiment.cfg file to set
hardware_bac=1 config_fast_sq2=1
