TC74VHC240,244F/FT/FK TOSHIBA CMOS Digital Integrated Circuit Silicon Monolithic TC74VHC240F, TC74VHC240FT, TC74VHC240FK TC74VHC244F, TC74VHC244FT, TC74VHC244FK Octal Bus Buffer TC74VHC240F/FT/FK Inverted, 3-State Outputs TC74VHC240F, TC74VHC244F TC74VHC244F/FT/FK Non-Inverted, 3-State Outputs The TC74VHC240 and 244 are advanced high speed CMOS 2 OCTAL BUS BUFFERs fabricated with silicon gate C MOS technology. They achieve the high speed operation similar to equivalent Bipolar Schottky TTL while maintaining the CMOS low power dissipation. TC74VHC240FT, TC74VHC244FT The 74VHC240 is an inverting 3-state buffer having two active-low output enables. The TC74VHC244 is a non-inverting 3-state buffer, and has two active-low output enables. These devices are designed to be used with 3-state memory address drivers, etc. An input protection circuit ensures that 0 to 5.5 V can be applied to the input pins without regard to the supply voltage. This device can be used to interface 5 V to 3 V systems and two supply systems such as battery back up. This circuit prevents device destruction due to mismatched supply and input voltages. TC74VHC240FK, TC74VHC244FK Features High speed: t = 3.9 ns (typ.) at V = 5 V pd CC Low power dissipation: I = 4 A (max) at Ta = 25C CC High noise immunity: V = V = 28% V (min) NIH NIL CC Power down protection is provided on all inputs. Balanced propagation delays: t t pLH pHL Wide operating voltage range: V = 2 to 5.5 V CC (opr) Weight Low noise: V = 0.8 V (max) OLP SOP20-P-300-1.27A : 0.22 g (typ.) Pin and function compatible with 74ALS240/244 TSSOP20-P-0044-0.65A : 0.08 g (typ.) VSSOP20-P-0030-0.50 : 0.03 g (typ.) Start of commercial production 1991-05 1 2014-03-01 TC74VHC240,244F/FT/FK Pin Assignment TC74VHC240 TC74VHC244 1 G 1 20 V 1G 1 20 V CC CC 1A1 2 19 2G 1A1 2 19 2G 2 Y4 18 1Y1 2Y4 18 1Y1 3 3 1A2 4 17 2A4 1A2 4 17 2A4 2 Y3 5 16 1Y2 2Y3 5 16 1Y2 1A3 6 15 2A3 1A3 6 15 2A3 2 Y2 7 14 1Y3 2Y2 7 14 1Y3 1A4 8 13 2A2 1A4 8 13 2A2 2 Y1 9 12 1Y4 2Y1 9 12 1Y4 GND 10 11 2A1 GND 10 11 2A1 (top view) (top view) IEC Logic Symbol TC74VHC240 TC74VHC244 (1) (1) 1G EN 1G EN (2) (18) (2) (18) 1A1 1Y1 1A1 1Y1 (4) (16) (4) (16) 1A2 1Y2 1A2 1Y2 (6) (14) (6) (14) 1A3 1Y3 1A3 1Y3 (8) (12) (8) (12) 1A4 1Y4 1A4 1Y4 (19) (19) 2G EN 2G EN (11) (9) (11) (9) 2A1 2Y1 2A1 2Y1 (13) (7) (13) (7) 2A2 2Y2 2A2 2Y2 (15) (5) (15) (5) 2A3 2Y3 2A3 2Y3 (17) (3) (17) (3) 2A4 2Y4 2A4 2Y4 Truth Table Inputs Outputs G A Y Y n n n L L L H L H H L H X Z Z X: Dont care Z: High impedance Y : TC74VHC244 n Yn : TC74VHC240 2 2014-03-01