MCE Power

The MCE power requirements are:

+Vcore	3V	5A
+Vlvd	4.5V	3A
+Va	6.2V	15A
-Va	-6.2V	2A
+Vah 1	10V	0.1A

¹: 10V supply only used when Readout Card Rev. B or Bias Card Rev. D is present in a subrack. 10V was used to generate reference voltages for DACs.

There are different solutions for powering up an MCE.

Linear Supplies

A straight-forward method is to use linear supplies configured to satisfy the above requirements. In that case the MCE has to be equipped with the right Linear-Feed connector in the front.

The 5-MDM MCE (72HP, SCUBA2 style) has 2 Circular Amphenol connectors in the front panel. Pinout is here:Amphenol pinout]

The 3-MDM MCE (48HP, Spider Style) has a Winchester MRA-34P-G connector in the front panel. Pinout can be found under Winchester connector, here : 48HP PSU Connector The Winchester connector is to be used with either linear supplies or switching supply (PSA). When using linear supplies, you can ignore connections that are "white" on that pinout. Those lines are few digital lines to monitor voltages of the switching supply and unused when used with Linear supplies.

As an example, here is how we setup our linear supplies in the lab. [Tom's Schematics and instructions]

Switching Supplies (AC-powered)

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 that can reside far from the MCE. The ACDC unit is designed and supplied by UBC.

So far, there has only been one incident that the switching noise was reported to be unacceptable.

See picture of 5-MDM MCE (72HP) powered by PSA+ACDCU[] See picture of 3-MDM MCE (48HP) powered by PSA+ACDCU[]

Switching Supplies (24V-in)

The MCE can alternatively be equipped with a 24V-in Switching supply to be used in balloon-based experiments. We are currently debugging the prototype design.