CY74FCT257T

D Function, Pinout, and Drive Compatible With FCT and F Logic D Reduced VOH (Typically = 3.3 V) Version of Equivalent FCT Functions D Edge-Rate Control Circuitry for Significantly Improved Noise Characteristics D Ioff Supports Partial-Power-Down Mode Operation D Matched Rise and Fall Times D Fully Compatible With TTL Input and Output Logic Levels D ESD Protection Exceeds JESD 22 − 2000-V Human-Body Model (A114-A) − 200-V Machine Model (A115-A) − 1000-V Charged-Device Model (C101) D 64-mA Output Sink Current 32-mA Output Source Current D 3-State Outputs CY74FCT257T QUAD 2-INPUT MULTIPLEXER WITH 3-STATE OUTPUTS SCCS019D − MAY 1994 − REVISED NOVEMBER 2001 Q OR SO PACKAGE (TOP VIEW) S I0a I1a Ya I0b I1b Yb GND 1 2 3 4 5 6 7 8 16 VCC 15 OE 14 I0c 13 I1c 12 Yc 11 I0d 10 I1d 9 Yd description The CY74FCT257T has four identical two-input multiplexers that select four bits of data from two sources under the control of a common data-select (S) input. The I0 inputs are selected when S is low, and the I1 inputs are selected when S is high. Data at the output is noninverted. The CY74FCT257T is a logic implementation of a four-pole, two-position switch, where the position of the switch is determined by the logic levels at S. Outputs are in the high-impedance state when the output-enable (OE) input is high. All but one device must be in the high-impedance state to avoid currents exceeding the maximum ratings if outputs are tied together. OE inputs must ensure that there is no overlap w...