1.4 GHZ NATURAL AIR-COOLING GAAS STANDARD CELL LSIS FOR 10 GBIT S OPTICAL COMMUNICATION-SYSTEMS/

Six chips of the GaAs standard cell LSIs have been developed for a syn chronous digital hierarchy (SDH) interface unit in 10 Gbit/s optical c ommunication systems. Two of them are the frame termination LSIs for S DH, and four are the byte multiplexing and demultiplexing LSIs. The LS I configuration with a careful thermal design were needed to realize a natural air-cooling operation. As a result, the unit was composed of eight chips with six kind of LSIs and these LSIs consist of 1 K to 3 K gates. The LSIs were designed with the standard cell libraries based on 0.5 mu m gate DCFL (Direct Coupled FET Logic) operating al a low po wer supply voltage of 1.5 V. The propagation delay time of standard DC FL inverter was 25 ps with a power consumption of 0.45 mW in the exper imental results. The LSI design methodology using these libraries were discussed to achieve the data processing of 1.25 Gbit/s signals under a natural air-cooling condition. The maximum operating speeds of them were at least 1.4 GHz and the power consumptions were as low as under 1.8 W, which resulted in fully high speed operations under a natural air-cooling condition at an ambient temperature of 100 degrees C.