Abstract: An integrated circuit package has multiple integrated circuits (ICs) mounted face down directly on one surface of a flexible circuit which is disposed in an opening of a rigid signal carrier, such as a pin grid array. The flexible circuit provides connections among the ICs, and also between the ICs and the signal carrier via wirebonds. The flexible circuit is attached to a rigid support ring that is bonded to the signal carrier adjacent to the opening. A thermally conductive lid covers the opening and contacts the backs of the ICs for heat removal. A rigid plate presses elastomeric pads against the other surface of the flexible circuit to maintain firm contact between the flexible circuit and the ICs and also between the ICs and the lid. The package may be hermetically sealed by attaching a cover to the support ring.

Abstract: Transceiver apparatus includes a transmitter circuit constructed with either emitter coupled logic (ECL) circuitry or programmable array logic circuitry, and a receiver circuit constructed with ECL circuitry. The transmitter circuit encodes a binary data signal received for transmission as a three-level modified duobinary encoded data signal and the receiver circuit decodes the received three-level encoded data signal to provide a binary data signal corresponding to the data signal received at the transmitter circuit for transmission. Both the transmitter and receiver circuits include features enabling transmitting and receiving high data-rate data signals.