The hybrid clamshell has been designed to remove noise increases at chip edges due to pickup on the pitch adapter. The hybrid clamshell consists on four main components: an aluminum base plate, an new ARCS FE with a hybrid-to-utri adapter mounted on plastic legs, a plastic pedestal which isolated the hybrid holder from the metal in the clamshell, and a thick metal lid. The lid+baseplate acts as a Faraday cage. The clamshell is grounded by a thick wire or ground braid between the hybrid-to-utri adapter's ground and the clamshell. All tests performed in the hybrid clamshell have had no noise increase at chip edges. The schematics of the clamshells at available here.
The module clamshell has been designed to remove noise pickup to levels such that open channels and pinholes acts as expected: opens will have a decreasing noise with load capacitance and pin-holed channel will be saturated. The module clamshell consists on five main components: an aluminum base plate, an new ARCS FE with a hybrid-to-utri adapter mounted on plastic legs, a plastic pedestal which isolated the hybrid holder from the metal in the clamshell, a thick metal lid, and an ARCS LED system mounted to the lid. The lid+baseplate acts as a Faraday cage. The clamshell is grounded by a thick wire or ground braid between the hybrid-to-utri adapter's ground and the clamshell. All tests performed in the module clamshell have shown common mode noise increase at less than the 0.5 ADC count level. The schematics of the clamshells are available here, here, and here.
Any questions about either clamshell can be sent to Anthony Affolder or Dave Hale