A 1.5V 7.5uW programmable gain amplifier for multiple biomedical signal acquisition

This paper presents a programmable analog front-end IC for multiple biomedical signal acquisition. By chopper-stabilized technique with an AC feedback circuit, the proposed circuit rejects differential electrode offset, common-mode disturbance and solves the problem of flicker noise. In TSMC 0.18µm CMOS process, the proposed circuit occupies an active area of 0.38mm2. With digital controls, the voltage gain, low-pass and high-pass cutoff frequency could be adjusted in the range of 52db–88db, 0.5Hz–10Hz and 100Hz–400Hz, respectively. With a supply voltage of 1.5V, the proposed circuit achieves an input-referred noise of 90nV∗Hz⁁−0.5, a noise-efficient factor of 6.1 while consuming a total current of 5µA.