Chip to Chip Driver
Original Publication Date: 1978-Apr-01
Included in the Prior Art Database: 2005-Feb-20
When chip-to-chip signalling must be carried out in the integrated circuit environment, reducing the I/O pin count per chip to a minimum is always an issue. Known double rail logic requires two signals, the logical normal and the logical inverse. To reduce this to one signal, a bipolar signal can be sent across the chip-to-chip boundary. A plus (+) signal is sent to indicate the normal, while a minus (-) signal is sent to indicate the inverse. Thus, if a logical signal `B' is to be sent, a plus (+) pulse is transmitted, while if the inverse, `B', is to be sent, a negative (-) pulse is transmitted. On the receiving chip, a detection scheme is required to distinguish between the two signals, and then additional circuitry is required to generate the original logical signals `B' and `B'.