Design of low power 12bit 40MSPS SAR ADCs with a redundancy algorithm and digital calibration for high dynamic range calorimeter readout

We present two SAR ADCs using a generalized redundant search algorithm and offering the flexibility to relax the requirements on the DAC settling time. Two more bits of redundancy allow also a digital calibration, based on a code density analysis to compensate the capacitors mismatching effects. A monotonic switching algorithm is used for these prototypes saving about 70% of dynamic power consumption compared to conventional switching algorithm. A fully differential was used for both prototypes featuring 12bit 40MS/s in a CMOS 130nm 1P8M process