Digitally programmable continuous-time biquad filter in 65-nm CMOS

This paper reports a new programmable G_m-C-OTA integrator and filter, which allows on-chip periodic analog signal generation and in essence, fulfils the function of the D/A converter. The method has the attributes of digital programming and control capability, robustness and reduced area overhead, which make it suitable for built-in self-test applications. The circuit has been fabricated in standard single poly, 65-nm CMOS with the core area of 0.11 mm² with a performance of 74 dB at 81 MHz, while consuming 9 mW.