MCE Power
Contents
Power Requirements
There are two types of MCE subracks:
- MCE72: contains up-to 10 cards and can read up to 32 columns. In the past, this also contained a power supply unit (PSU)
- MCE48: contains up-to 7 cards and can read up to 16 columns.
The power requirements of typical subrack configurations are given below. To compute power and current requirements for a particular configuration, use: http://e-mode.phas.ubc.ca/mce/cgi-bin/power.cgi .
| Configuration | MCE48 RC_RevE BC_RevF1 |
MCE72 RC_RevE BC_RevF0 | |
|---|---|---|---|
| Voltage | |||
| Vcore1 | 3.0V | 3.2A | 5.4A |
| Vlvd | 4.5V | 2.9A | 3.26A |
| Va+ | 6.2V | 3.5A | 6.4A |
| Va− | −6.2V | 1.0A | 2.3A |
| Vah2 | 10.0V | — | — |
| Total Power | 50.1W | 85.0W | |
1: Minimum Vcore supply for older version of cards can be as low as 2.5V, but newer RC and BC require minimum 3V see note. The numbers in this table assume a Vcore of 3V.
2: The 10V Vah supply is only used when Readout Card Rev. B (or older) or Bias Card Rev. D (or older) are present in the subrack. Vah was used to generate reference voltages for DACs.
3: When using mux11d squid chips, unused DACs on Address Card can be turned off and 1 Bias Card can be eliminated. This will amount to 10W of power savings.
For card specific power requirements, see MCE Card Specific Power Requirements
Connector & pinout
The MCE uses Winchester MRA-34P-G on the front panel.
| A +Vah* +10V |
B AGND | ||
| C −Va −6.2V |
D AGND | ||
| E +Va +6.2V |
F AGND | ||
| H +Va +6.2V |
J AGND | ||
| K +Va +6.2V |
L AGND | ||
| M +Va +6.2V |
N DGND | ||
| P +Vlvd +4.5V |
R DGND | ||
| S +Vlvd +4.5V |
T DGND | ||
| U +Vlvd +4.5V |
V DGND | ||
| W +Vcore +3.0V |
X DGND | ||
| Y +Vcore +3.0V |
Z DGND | ||
| a +Vcore +3.0V |
b DGND | ||
| c CC_SREQ† |
d PS_MOSI† | ||
| f Fan GND‡ |
g BRST† | ||
| h CC_MISO† |
i PS_SCLK† | ||
| j Fan +12V‡ |
k PS_CS† | ||
| m SIG_RET† |
n SIG_RET† | ||
*: Obsolete: Vah is used only by revB Readout Cards and revD Bias Cards (or earlier)
†: Obsolete: was used to communicate with the PSUC.
‡: Optional power lines for subrack top plate fans.
Full details can be found under Winchester connector, here: 48HP Front-Panel Power Connection
Note that the older 5-MDM SCUBA-2 style MCE had 2 Circular Amphenol connectors on the front panel of the linear feed card. Pinout is here: Amphenol pinout. The linear-feed card connects power from these circular connectors to the Winchester power connector on the back panel.
schematics for Winchester-Winchester cable to connect MCE to a Vicor supply is listed here: [1]
Powering up an MCE
There are different solutions for powering up an MCE. A straight-forward method for all ground-based experiments is to use linear supplies configured to satisfy the above requirements.
Vicor Switching Supplies (24V-in)
The MCE can alternatively be equipped with a 18–36Vin (24Vin nominal) switching supply designed for use in balloon-based experiments. It uses Vicor bricks. :See Vicor Power Supply
Linear Supplies
The set of linear supplies listed below (or similar supplies) are suitable.
Option 1
| +Vcore | IHC5-6/OVP (adjustable) | 3V | 5A |
|---|---|---|---|
| +Vlvd | IHB5-3/OVP | 4.5V | 3A |
| +Va | IHE5-18/OVP | 6.2V | 15A |
| −Va | IHB5-3/OVP | -6.2V | 2A |
| +Vah1 | IHA15-0.5 | 10V | 0.1A |
1: +Vah or 10V supply only used when Readout Card Rev. B or Bias Card Rev. D is present in a subrack.
- Open-Frame PSU Wiring, Bill-of-Materials, Assembly Instructions
- MCE-to-PS Cable Wiring , Bill-of-Material
Option 2
| +Vcore | Kepco JQE 6-22M (adjustable) |
|---|---|
| +Vlvd | Power One HC5-6/OVP |
| +Va | Kepco JQE 15-25M (adjustable) |
| −Va | Kepco JQE 15-25M (adjustable) |
| +Vah1 | Power One HAD15-0.4-A |
1: +Vah or 10V supply only used when Readout Card Rev. B or Bias Card Rev. D is present in a subrack.
As a slightly out-of-date example, here is how we setup our linear supplies in the lab (for 1 MCE).
AC-powered Switching Supplies (obsolete)
The MCE can be equipped with a switching supply (PSA) that is powered through a front-panel Amphenol connector that takes ±150V DC. The ±150V is generated by an external AC-DC Unit (ACDCU) that can reside far from the MCE. The ACDCU is designed and supplied by UBC.
The PSA is equipped with a controller card (PSUC) that allows monitoring voltage/current levels of the MCE by issuing a command from the MCE control PC. See psc_status.
This solution is obsolete and no longer in production. Ground-based experiments should use linear supplies. For balloon-based experiments, use the 24-V Vicor supply.
