SN74F543 Datasheet | Texas Instruments

description The SN74F543 octal transceiver contains two sets of D-type latches for temporary storage of data flowing in either direction. Separate latch-enable (LEAB or LEBA) and output enable (OEAB or OEBA) inputs are provided for each register to permit independent control in either direction of data flow. The A outputs are characterized to sink 24 m A while the B outputs are characterized to sink 64 m A. DB, DW, OR NT PACKAGE (TOP VIEW) LEBA 1 OEBA 2 A1 3 A2 4 A3 5 A4 6 A5 7 A6 8 A7 9 A8 10 CEAB 11 GND 12 24 VCC 23 CEBA 22 B1 21 B2 20 B3 19 B4 18 B5 17 B6 16 B7 15 B8 14 LEAB 13 OEAB The A-to-B enable (CEAB) input must be low in order to enter data from A or to output data from B. Having CEAB low and LEAB low makes the A-to-B latches transparent; a subsequent low-to-high transition of LEAB puts the A latches in the storage mode. With CEAB and OEAB both low, the 3-state B outputs are active and reflect the data present at the output of the A latches. Data flow from B to A is similar, but requires using the CEBA, LEBA, and OEBA inputs. The SN74F543 is available in TI’s shrink small-outline package (DB), which provides the same I/O pin count and functionality of standard small-outline packages in less than half the printed-circuit-board area. The SN74F543 is characterized for operation from 0°C to 70°C. FUNCTION TABLE† INPUTS OUTPUT CEAB LEAB OEAB A B0‡ † A-to-B data flow is shown; B-to-A flow control is the same except that it uses CEBA, LEBA, and OEBA. ‡ Output level before the indicated steady-state input conditions were...