8 Bit 125Ms/S Pipelined ADC

Pipeline Stage Amplifier

Obsidian has experience with pipline ADC design for communications analog front ends.

Made from a stack of 1.5 bit switched cap ADC's. The most critical element is the differential stage amplifier: a folded cascodes are used with an additional source follower stage prior to the pre-drive for extra speed.

Excellent dynamic characteristics are needed for the system to settle within one clock cycle. For this 8 bit solution trimming is not required.

A 10 bit version of the same design adds triming for gain and offset.