Tetsu Nagamatsu

A 0.9-V, 150-MHz, 10-mW, 4 mm/sup 2/, 2-D discrete cosine transform core processor with variable threshold-voltage (VT) scheme

This two-dimensional 8/spl times/8 discrete cosine transform (DCT) core processor for portable multimedia equipment with HDTV-resolution in a 0.3 /spl mu/m CMOS triple-well double-metal technology operates at 150 MHz from a 0.9 V power supply and consumes 10 mW, only 2% power dissipation of a previous 3.3 V DCT. Circuit techniques for dynamically varying threshold voltage reduce active power dissipation with negligible overhead in speed, standby power and chip area.

A 200 MHz 13 mm/sup 2/ 2-D DCT macrocell using sense-amplifying pipeline flip-flop scheme

The two-dimensional discrete cosine transform (2D DCT) has been widely recognized as a key processing unit for image data compression/decompression. In this paper, the implementation of a 200 MHz 13.3 mm/sup 2/ 8/spl times/8 2-D DCT macrocell capable of HDTV rates, based on a direct realization of the DCT, and using distributed arithmetic is presented. The macrocell, fabricated using 0.8 /spl mu/m base-rule CMOS technology and 0.5 /spl mu/m MOSFETs, performs the DCT processing with 1 sample-(pixel)-per-clock throughput. The fast speed and small area are achieved by a novel sense-amplifying pipeline flip-flop (SA-F/F) circuit technique in combination with nMOS differential logic. The SA-F/F, a class of delay flip-flops, can be used as a differential synchronous sense-amplifier, and can amplify dual-rail inputs with swings lower than 100 mV. A 1.6 ns 20 bit carry skip adder used in the DCT macrocell, which was designed by the same scheme, is also described. The adder is 50% faster and 30% smaller than a conventional CMOS carry look ahead adder, which reduces the macrocell size by 15% compared to a conventional CMOS implementation. >

200 MHz video compression macrocells using low-swing differential logic

Improving the performance of fully dedicated macrocells is key to realizing HDTV-resolution video de/compression LSIs operating at more than 100 MHz, having reasonable power consumption and chip size small enough for consumer applications. Existing circuit techniques are either not sufficiently fast or are area consuming. However, these problems are overcome by using low-swing differential logic to realise such macrocells.<<ETX>>

A single-chip MPEG2 video decoder LSI

This MPEG2 video decoder LSI decodes MPEG2 standard bit streams. The compression algorithm in the MPEG2 is based on discrete cosine transform (DCT), variable length coding, and motion compensation similar to the MPEG1, the earlier standard. However, the processing speed should be more than four times faster than MPEG1. Moreover, several algorithms and structures to handle interlaced pictures are added to the MPEG1 standard. This LSI decodes in real time all motion-compensation modes and picture structures in MPEG2 bit streams of not only CCIR601 but also HDTV resolution.<<ETX>>

A 5 Gb/s 8/spl times/8 ATM switch element CMOS LSI supporting five quality-of-service classes with 200 MHz LVDS interface

The switch element (SE) is a 622Mb/s, 8/spl times/8 shared-buffer ATM switch LSI for backbone LAN and WAN applications. The SE has 5 Gbps bandwidth, supporting 5 QoS classes delay priority and link-by-link multicast. Up to a 32/spl times/32 switch with 20 Gbps bandwidth can be configured using multiple SEs and distributor/arbiter (DA) LSIs.

0.5- mu m 3.3-V BiCMOS standard cells with 32-kilobyte cache and ten-port register file

BiCMOS standard cell macros, including a 0.5-W 3-ns register file, a 0.6-W 5-ns 32-kbyte cache, a 0.2-W 3-ns table look-aside buffer (TLB), and a 0.1-W 3-ns adder, are designed with a 0.5- mu m BiCMOS technology. A supply voltage of 3.3 V is used to achieve low power consumption. Several BiCMOS/CMOS circuits, such as a self-aligned threshold inverter (SATI) sense amplifier and an ECL HIT logic are used to realize high-speed operation at the low supply voltage. The performance of the BiCMOS macros is verified using a fabricated test chip. >

0.5/spl mu/m 2M-transistor BipnMOS Channelless Gate Array

A channelless gate array has been realized using 0.5- mu m BiCMOS technology integrating more than two million transistors on a 14-mm*14.4-mm chip. A small-size PMOS transistor and a small-size inverter are added to the conventional BiNMOS gate to form the BiPNMOS gate. The gate is suitable for 3.3-V supply and achieves 230-ps gate delay for a two-input NAND with full-swing output. Added small-size MOS transistors in the BiPNMOS basic cell can also be used for memory macros effectively. A test chip with four memory macros-a high-speed RAM, a high-density RAM, a ROM, and a CAM macro-was fabricated. The high-speed memory macros utilize bipolar transistors in bipolar middle buffers and in sense amplifiers. The high-speed RAM macro achieves an access time of 2.7 ns at 16-kb capacity. The high-density RAM macro is rather slow but the memory cell occupies only a half of the BiPNMOS basic cell using a single-port memory cell. >

A 350 ps 50 K 0.8 amu;m BiCMOS gate array with shared bipolar cell structure

A BiCMOS gate array with gate delay of 350 ps has been realized by 0.8-μm BiCMOS technology. Minimum gate delay and cell area have been achieved with a shared bipolar cell structure. The gate delay is almost equivalent to that of a 0.5-μm pure CMOS gate array. The cell-area increase is to only 25% compared with a 0.8-μm pure CMOS cell. I/O cells can interface with CMOS, TTL (transistor-transistor logic), and ECL (emitter-coupled logic) chips at the same time with a single supply voltage of 5 V

0.5 mu m BiCMOS standard-cell macros including 0.5 W 3 ns register file and 0.6 W 5 ns 32 kB cache

BiCMOs standard-cell macros, including a 0.5-W, 3.0-ns register file, a 0.6-W, 5.0-ns 32-kB cache, a 0.2-W, 2.5-ns table look-aside buffer (TLB), and a 0.1-W, 3.0-ns adder, are presented based on a 0.5- mu m BiCMOs technology. These power consumption values are at 100 MHz operation. Low power and high speed are crucial for high-performance systems requiring a high level of integration. Several BiCMOS/CMOS circuits achieve high-speed operation with a 3.3-V supply. A direct-coupled ECL (emitter-coupled logic)+CMOS circuit is investigated for use as a BiCMOS standard cell.<<ETX>>