74ABT646 Datasheet | Fairchild Semiconductor

74ABT646 Octal Transceivers and Registers with 3-STATE Outputs April 1992 Revised November 1999 74ABT646 Octal Transceivers and Registers with 3-STATE Outputs General Description The ABT646 consists of bus transceiver circuits with 3STATE, D-type flip-flops, and control circuitry arranged for multiplexed transmission of data directly from the input bus or from the internal registers. Data on the A or B bus will be clocked into the registers as the appropriate clock pin goes to a high logic level. Control OE and direction pins are provided to control the transceiver function. In the transceiver mode, data present at the high impedance port may be stored in either the A or the B register or in both. The select controls can multiplex stored and real-time (transparent mode) data. The direction control determines which bus will receive data when the enable control OE is Active LOW. In the isolation mode (control OE HIGH), A data may be stored in the B register and/or B data may be stored in the A register. Features s Independent registers for A and B buses s Multiplexed real-time and stored data s A and B output sink capability of 64 m A, source capability of 32 m A s Guaranteed output skew s Guaranteed multiple output switching specifications s Output switching specified for both 50 p F and 250 p F loads s Guaranteed simultaneous switching noise level and dynamic threshold performance s Guaranteed latchup protection s High impedance glitch free bus loading during entire power up and power down cycle s Nondestructive hot insertion capability Ordering Code: Order Number 74ABT646CSC 74ABT646CMSA 74ABT646CMTC Package Number M24B MSA24 MTC24 Package Description 24-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-153, 4.4mm Wide 24-Lead Shrink Small Outline Package (SSOP), EIAJ TYPE II, 5.3mm Wide 24-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide Device also available in Tape and Reel. Specify by appending suffix letter “X” to the ordering...