Inventors:
Anthony G. Aipperspach - Rochester MN
Gerard Boudon - Mennecy, FR
Allan H. Dansky - Poughkeepsie NY
Pierre Mollier - Boissise Le Roi, FR
Ieng Ong - Anthony, FR
Nghia Phan - Rochester MN
Biagio Pluchino - Poughkeepsie NY
Steven J. Zier - Hopewell Junction NY
Adrian Zuckerman - Poughkeepsie NY
Assignee:
International Business Machines Corporation - Armonk NY
International Classification:
H03K 1704
Abstract:
A multi emitter multi input BICMOS NAND circuit (30) is provided wherein an output node OUT connected to an output terminal (33) is coupled between pull up (31) and pull down (32) blocks. According to one embodiment of the present invention, the pull up block (32) is comprised of a plurality of identical basic cells, each comprised of a CMOS inverter (C31, C32) driving an NPN pull up transistor (T31, T32) mounted as an emitter follower. Logic signals (A31, A32) are applied on the inputs of the inverters (C31, C32), and the inverted signal (A31, A32) is available at the emitter of the emitter follower which corresponds to the output of the cell. All outputs are tied altogether to perform an OR function and are connected to said output terminal (33) to have a multi emitter like circuit. The pull down block (32) in this embodiment is comprised of 2 FETs (F31, F32) serially connected between said output node OUT and a discharge device such as a feedback NFET (Z) the gate of which is connected to said output node OUT. These 2 FETs are for driving a NPN pull down transistor (T), the collector of which is also connected to the output node OUT.