BICMOS local address transition detection circuit
 A plurality of local address transition detector (LATD) circuits, one per address bit signal (Ai), of the type used in SRAMs to generate an on-chip clock pulse (LATDSi) that insures a correct timing of internal circuits such as sense amplifiers and address decoders that are essential for a correct READ/WRITE operation of the SRAM. According to one aspect of the invention, each LATD circuit includes: a first bipolar transistor (T1) serially connected with a first FET device (N1) forming a first branch; a second bipolar transistor (T2) serially connected with a second FET device (N2) forming a second branch. The first and second branches are connected in parallel between a first supply voltage (Vcc) and a common output node (N) connected to a circuit output terminal (30-i) where the output signal (LATDSi) generated by the LATD circuit (22-i) is available. The first and second bipolar transistors (T1, T2) are respectively driven by the address signal (Ai') and its complement (Ai') at the ECL voltage levels and the second and first FET devices are respectively driven by the address signal (Ai*' ) and its complement (Ai*') at the CMOS voltage levels. As a result of this design of the LATD circuit, the delays in critical paths in BICMOS circuits incorporating the LATD circuit may be significantly reduced relative to BICMOS circuits utilizing conventional LATD circuits. 
International Business Machines Corporation
G
G11C
inventional
Bertrand Philippe Michel
Gabillard Girard Grandguillot