An adaptive multimode constant voltage (CV) control scheme for primary-side regulation flyback converters operating in discontinuous conduction mode and continuous conduction mode operation is presented, which significantly enhances the light-load efficiency and thereby the overall average efficiency. Compared to conventional control scheme, the proposed control scheme performs analog control approach to integrate multiple operating modes adaptively based on load conditions. Besides, line voltage compensation and freewheeling diode compensation are proposed to improve the CV precision operating in multiple modes. The proposed adaptive multimode control scheme is implemented in 0.18 μ m 5 V/40 V BCD process and occupies a die size (with pads) of 1.05×0.8 mm ² . The experimental results show that the average efficiency is 88.52% under 265 Vac, whereas peak efficiency can reach 89.65% under 265 Vac. The deviation of the output voltage is within ± 2.33%.

In a traditional quasi-resonant (QR) control flyback converter, the switching frequency of the system will increase with the decrease of the load, so the switching loss under the light load becomes high, which greatly affects the average efficiency of the system in the whole load range. An improved QR control method called valley skip (VS) control can reduce the switching loss by decreasing the frequency of the system under the light load. However, the switching frequency of the conventional VS controller may change suddenly at some load points, and this sudden frequency hopping causes serious audible noise in the transformer. In this article, we propose a valley-locking control scheme to overcome the shortcomings of the traditional VS control technology. It can eliminate the audio noise caused by the frequency hopping in VS control. In order to verify the feasibility of the proposed method, a controller IC is fabricated with the proposed method and tested by a prototype experimental board of 24 W/12 V.

With the increasing complexity of modern design, mixed-cell-height designs have become more popular, which makes the legalization problem more challenging. In this article, a robust negotiation-based legalizer (NBLG) is proposed to reduce average displacement and maximum displacement for mixed-cell-height circuits with considering the fence region and technology constraints. By dissecting the main components of the negotiation-based method, we divide the placement grid in terms of placement sites and reformulate the legalization problem as a resource allocation task. We then allow all movable cells to gradually remove overlaps in a surrounding window with two individual techniques: 1) isolation point and 2) adaptive penalty function. We also adopt a deterministic multithreading technique to accelerate the convergence of our algorithm. Experimental results show that our legalizer achieved the minimal average displacement and maximum displacement in a reasonable runtime compared with state-of-the-art methods.

These days, demand for small volume and low cost of the home automation device is getting higher and higher. Converter with single-stage scheme has advantages of simple structure, low cost, and small theoretical volume, but it often suffers bad output accuracy in low output voltage applications. This brief proposes a constant voltage compensation circuit for AC/DC converters to improve the output accuracy which can also be used in a BUCK AC/DC converter with low output voltage. To verify the feasibility of the proposed compensation method, a BUCK controller based on the proposed circuit is implemented in Episil $0.5~\mu \text{m}$ /40V-HVCMOS process and occupies a die size of $0.99{\times }0.8$ mm ² . By the help of the proposed circuit, the output accuracy of the prototype with single-stage structure, which has advantages of small volume and low cost, can reach as high as those converters with multi-stage structure. Test results show that the load regulation of the prototype is about 1.3% with 3.3V output and less than 0.9% with 5V and 12V outputs.

For low cost and wide power range, the constant current (CC) control scheme for multimode primary-side regulation (PSR) flyback converter is prevalent in low and medium power applications. Although some multimode CC control schemes have been presented to raise CC accuracy, the current deviation caused by the mode conversion and inherent propagation delay remains unsolved. An improved CC control scheme is adopted to mitigate the influence of propagation delay or mode conversion on CC accuracy, which can be added into an IC controller with no extra pin penalty. The proposed scheme is implemented in $0.18\mu \text{m}$ 5V/40V BCD process. The experimental results reveal that the deviation of the output current is within ± 0.8% under different input and load conditions.

As chip manufacturing approaches physical limits, the probability of defects due to specific chip layout structures has significantly increased. These defect-prone structures are known as lithographic hotspots. Pattern matching method is widely used in hotspot detection algorithms due to its efficiency and accuracy. However, traditional pattern matching algorithms face major challenges in both solution efficiency and flexibility for fuzzy matching. To overcome these limitations, an integer range-based DFA (r-DFA)-based layout pattern matching method supporting parallelization and fuzzy matching is proposed. Manhattan polygons in the layout are represented as multiple path strings, thereby transforming the pattern matching problem into a string regular expression search problem. To simplifies the construction of large integer range elements in fuzzy matching, the r-DFA is employed, enhancing construction efficiency and enabling the algorithm to achieve linear time complexity. Moreover, this approach focuses most of the matching process within each individual layout polygon, enabling parallelized matching across diverse layout polygons. Compared to the state of the art, our approach supports fuzzy matching, and shows an average efficiency improvement of 1.23 times.