1. 1 ABC130 Module Envelope Envelope set by 2 locations 1.Power end – biggest contribution coming from shield box 2.Data I/O end – set by wire bonding from asic-to-sensor Power EndData I/O

2. 2 Module Envelope – Present DCDC board Current DCDC power with commercial coil (Abracon 120nH, 3.5mm height) Sensor Hybrid Polyimide Cap COIL Shield Box 3.5 0.3 0.4 Core 4.8 Assume glue layers are 100µm Power envelope ~4.8mm (core to top of shield box) For a FR4 version: 5.1mm Envelope for asic-to-sensor bonding ~ 1.9mm 0.5 asic Cap 1.0 1.9 asic Cap 1.0 1.9 0.8

3. 3 Module Envelope – future converter (worst case) Future DCDC power with CERN converter and commercial coil (Abracon 422nH, 4.6mm height) Sensor Polyimide Cap COIL Shield Box 4.6 0.3 0.4 Core 5.9 Assume glue layers are 100µm Power envelope ~5.9mm (core to top of shield box) For a FR4 version: 6.1mm Envelope for asic-to-sensor bonding ~ 1.9mm 0.5 asic Cap 1.0 1.9 Hybrid 0.8

4. 4 Flat coil option – large inductor value with reduced profile For flat coil 2 options exist: Coil mounted above converter – utilising the volume above the regulator Envelope set by coil + converter + clearances Overall envelope ~4.8mm (5.1mm for FR4 variant) Benefits from having reduced PCB footprint, releases real state for HV mux Expect PCB to be ~40mm length Second, lowest profile, option: Coil mounted towards end of PCB, envelope set by SMDs and not coil Largest SMD comes in at 2mm Allowing for 1.0mm shield box clearance would require a 3mm high shield box Overall envelope ~3.8mm (4.1mm for FR4 variant) But price paid is large PCB footprint, increases by additional 20mm (~60mm board length) Additional real estate used simply to accommodate coil (provides no electrical function) This solution proposed...

5. 5 Module Envelope – future converter with flat coil Future DCDC power with CERN converter with custom Wurth flat coil (540nH, 1.2mm height) Sensor Polyimide COIL Shield Box 0.3 0.4 Core 4.8 Assume glue layers are 100µm Power envelope ~4.8mm (core to top of shield box) For a FR4 version: 5.1mm Envelope for asic-to-sensor bonding ~ 1.9mm Buck reg 0.8 1.0 1.2 1.0 asic Cap 1.0 1.9 Hybrid asic Cap 1.0 1.9 0.8

6. 6 Summary Targeting <5mm in Z for module envelope From stave core face Prototype converters using commercial regulators show this is possible 4.8mm envelope (but with low value inductor) Inductor increases in size as inductance increases Latest radiation tolerant asics from CERN suggest usage of large value inductors COTS based inductor results in a module envelope of 5.9mm Use of an externally mounted custom flat coil reduces the envelope to <4.8mm Scope to reduce this further if a lower value inductor is shown to work Does future proof the board if found necessary to retain large coil values