Recent efforts have focused on wireless ingestible sensing capsules, but challenges remain in miniaturization, sensor integration, and energy efficiency. This paper presents GISMO-A, an ingestible capsule integrating a custom-designed application-specific integrated circuit (ASIC) for low-power biochemical sensing. The ASIC enables pH and oxidation-reduction potential (ORP) measurements at an average power consumption of 172 μ W, representing a 70% reduction compared to the previously published GISMO capsule. GISMO-A supports a 6-second measurement interval, resulting in a threefold increase in data density relative to GISMO. Validated through in-vitro and in-vivo experiments, GISMO-A represents a significant advancement in the design of energy-efficient, miniaturized GI Tract sensing systems.
