This paper presents a biopotential acquisition unit with an instrumentation amplifier and analog-to-information converter for wearable health monitoring applications. The instrumentation amplifier defines the quality of the acquired biopotential signals. At the heart of the system is an Analog to Information Converter (AIC) to enables the random undersampling operation. AIC is used to digitize the output of the biopotential instrumentation amplifier. Both instrumentation amplifier and AIC are implemented in 65nm CMOS technology. The simulation results show that the proposed instrumentation amplifier has a CMRR of 100.18 dB and noise of 35.89nV/sqrt (Hz). AIC achieves a sampling rate of 0.5 KS/s, an ENOB 9.54 bits, FOM 187 fj/conv-step and consumes 69.66 nW from 1 V power supply.