This paper proposes a mixed-size 3D analytical placement framework for face-to-face stacked integrated circuits fabricated with heterogeneous technology nodes and connected by hybrid bonding technology. The proposed framework efficiently partitions a given netlist into two dies and optimizes the positions of each macro, standard cell, and hybrid bonding terminal (HBT). A multi-technology objective function and a multi-technology density penalty calculation process are adopted to handle the heterogeneous-technology-node constraints during mixed-size 3D global placement. Furthermore, a 3D objective function is used to refine the placement result during HBT-cell co-optimization. Our placer achieves the best results for all contest test cases compared with the participating teams at the 2023 CAD Contest at ICCAD on 3D Placement with Macros.

A 3rd-order feedforward high-pass sigma-delta modulator (HPSDM) with operational amplifier (op-amp) sharing and noise-coupling techniques is presented in this paper. The modulator is suitable for biomedical signal acquisition with features of high resolution and low power consumption. Op-amp sharing technique has been utilized to reduce the number of amplifiers. To add an additional noise-shaping order, the noise-coupling technique is embedded in the summing stage without additional amplifier. To overcome the circuit sensitivity to process variation and capacitor mismatch, a new high-pass integrator structure is proposed. Simulation results reveal a Signal-to-Noise and Distortion Ratio (SNDR) of 79.64 dB consuming 1.31 $\mu$W under 1.2 V supply voltage, which can achieve peak Schreier Figure-of-Merit (FoM) of 161.64 dB and peak Walden FoM of 0.4 pJ/conv.

A high-pass sigma-delta modulator (HPSDM) that uses operational amplifier (op-amp) sharing and programmable feed-forward coefficients is presented for an electrocardiography (ECG) signal detection system. Op-amp sharing is used to reduce the quantity of amplifiers because they dominate the entire power consumption of the HPSDM. Moreover, the amplitude of the ECG varies from person to person; hence, programmable feed-forward coefficients are used to adjust the dynamic range of HPSDM to obtain high resolution across users. This technique is implemented using the 0.18 μm standard CMOS process. Measurement results reveal that the proposed HPSDM has a signal-to-noise and distortion (SNDR) of 54.5 dB and a power of 2.25 μW under a 1.2 V supply voltage to achieve the figure of merit of 12.96 pJ/conv. In terms of other settings, the proposed HPSDM has an SNDR of 64.8 dB and a power of 5.2 μW under a 1.8 V supply voltage to achieve the figure of merit of 9.15 pJ/conv. Both modes extend the dynamic range of 12 dB according to the programmable feed-forward coefficients.