Makoto Furihata

A monolithic video frequency filter using NIC-based gyrators

In consumer electronic video products, one of the most important problems is to build filters in LSI system. The authors have presented an LC simulation synthesis of balanced-type active RC filters using NIC-based gyrators [1]. Since the proposed method have required only npn transistors with better frequency characteristics than those of pnp transistors, excellent frequency responses can have been obtained even at video frequencies. Therefore, the filters are suitable for video signal processing and can be easily implemented by a consumer electronic bipolar process. However, time constants of the circuits depend on device technology, and it is difficult to determine cutoff or center frequencies of the filters precisely.

100-MHz monolithic low-pass filters with transmission zeros using NIC integrators

A monolithic method of implementing VHF filters with transmission zeros is presented. The transmission zeros are obtained using a modified leapfrog simulation method realized without floating capacitors that does not require summing circuits inside the feedback loops. The integrators used are balanced negative impedance converter (NIC) integrators with grounded capacitors, which do not require p-n-p transistors and are suited for low-voltage applications. A low-pass filter with a cutoff frequency of 100 MHz and with a transmission zero at 166 MHz designed and built in an integrated circuit form showed good results, confirming the feasibility of the method. >

A synthesis of 100 MHz monolithic third-order lowpass filters with a transmission zero

Proposes an implementation of a monolithic filter with a 100 MHz cutoff frequency and a 200 MHz transmission zero. The method is based on the modified leapfrog simulation and requires no floating capacitors. Integrators are realized by balanced-type NICs because the NICs have excellent high frequency characteristics. Results of computer simulation are also presented

A Highly Efficient Design System for Mixed Analog/Digital LSIs

An engineering system aimed to the highly efficient design of analog and/or mixed analog/digital custom LSIs is described. The system covers the areas of the system design using a new function level simulator, the circuit design and the layout by a circuit library and a layout library. The effectiveness of this engineering system is demonstrated through the design of a mixed analog/digital custom LSI for VCR use with about 5000 elements. This system has achieved the design efficiency of more than 1.5 times compared with the conventional methods.

A One-chip Monolithic Chroma Processing IC for Color Television Receivers

カラーテレビ受像機へ多機能ICを採用することには多くの利点がある.本報告は, 1チップクロマICの開発において遭遇した, 多機能集積化にともなう内部相互干渉, 温度特性, 外部端子数の制約の問題に関し, 回路設計面からの解決法を述べたものである.なお現在本ICは量産化されている.