TC74HCT240,244AP/AF TOSHIBA CMOS Digital Integrated Circuit Silicon Monolithic TC74HCT240AP, TC74HCT240AF TC74HCT244AP, TC74HCT244AF Octal Bus Buffer with TTL Input Level TC74HCT240AP/AF Inverted, 3-State TC74HCT240AP, TC74HCT244AP Outputs TC74HCT244AP/AF Non-Inverted, 3-State Outputs The TC74HCT240A, and HCT244A are high speed CMOS 2 OCTAL BUS BUFFERs fabricated with silicon gate C MOS technology. They achieve the high speed operation similar to equivalent TC74HCT240AF, TC74HCT244AF LSTTL while maintaining the CMOS low power dissipation. Their inputs are compatible with TTL, NMOS, and CMOS output voltage levels. The TC74HCT240A is an inverting 3-state buffer having two active-low output enables. The TC74HCT244A is non-inverting 3-state buffer the HCT244A has two active-low output enables. These devices are designed to be used with 3-state memory address drivers, etc. All inputs are equipped with protection circuits against static discharge or transient excess voltage. Weight DIP20-P-300-2.54A : 1.30 g (typ.) SOP20-P-300-1.27A : 0.22 g (typ.) Features High speed: t = 13 ns (typ.) at V = 5 V pd CC Low power dissipation: I = 4 A (max) at Ta = 25C CC Compatible with TTL outputs: V = 0.8 V (max) IL V = 2.0 V (min) IH Wide interfacing ability: LSTTL, NMOS, CMOS Output drive capability: 15 LSTTL loads Symmetrical output impedance: I = I = 6 mA (min) OH OL Balanced propagation delays: t t pLH pHL Wide operating voltage range: V (opr) = 2 to 6 V CC Pin and function compatible with 74LS240/244 Start of commercial production 1986-05 1 2014-03-01 TC74HCT240,244AP/AF Pin Assignment TC74HCT240A TC74HCT244A IEC Logic Symbol TC74HCT240A TC74HCT244A Truth Table Inputs Outputs G A Y Y n n n L L L H L H H L H X Z Z : For TC74HCT240A only X: Dont care Z: High impedance 2 2014-03-01