d a t a sh eet product speci?cation file under integrated circuits, ic06 december 1990 integrated circuits 74hc/hct244 octal buffer/line driver; 3-state for a complete data sheet, please also download: the ic06 74hc/hct/hcu/hcmos logic family specifications the ic06 74hc/hct/hcu/hcmos logic package information the ic06 74hc/hct/hcu/hcmos logic package outlines
december 1990 2 philips semiconductors product speci?cation octal buffer/line driver; 3-state 74hc/hct244 features output capability: bus driver i cc category: msi general description the 74hc/hct244 are high-speed si-gate cmos devices and are pin compatible with low power schottky ttl (lsttl). they are specified in compliance with jedec standard no. 7a. the 74hc/hct244 are octal non-inverting buffer/line drivers with 3-state outputs. the 3-state outputs are controlled by the output enable inputs 1 oe and 2 oe. a high on n oe causes the outputs to assume a high impedance off-state. the 244 is identical to the 240 but has non-inverting outputs. quick reference data gnd = 0 v; t amb =25 c; t r =t f = 6 ns notes 1. c pd is used to determine the dynamic power dissipation (p d in m w): p d =c pd v cc 2 f i +? (c l v cc 2 f o ) where: f i = input frequency in mhz f o = output frequency in mhz ? (c l v cc 2 f o ) = sum of outputs c l = output load capacitance in pf v cc = supply voltage in v 2. for hc the condition is v i = gnd to v cc for hct the condition is v i = gnd to v cc - 1.5 v ordering information see 74hc/hct/hcu/hcmos logic package information . symbol parameter conditions typical unit hc hct t phl / t plh propagation delay 1a n to 1y n ; 2a n to 2y n c l = 15 pf; v cc =5v 9 11 ns c i input capacitance 3.5 3.5 pf c pd power dissipation capacitance per buffer notes 1 and 2 35 35 pf
december 1990 3 philips semiconductors product speci?cation octal buffer/line driver; 3-state 74hc/hct244 pin description pin no. symbol name and function 11 oe output enable input (active low) 2, 4, 6, 8 1a 0 to 1a 3 data inputs 3, 5, 7, 9 2y 0 to 2y 3 bus outputs 10 gnd ground (0 v) 17, 15, 13, 11 2a 0 to 2a 3 data inputs 18, 16, 14, 12 1y 0 to 1y 3 bus outputs 19 2 oe output enable input (active low) 20 v cc positive supply voltage fig.1 pin configuration. fig.2 logic symbol. fig.3 iec logic symbol.
december 1990 4 philips semiconductors product speci?cation octal buffer/line driver; 3-state 74hc/hct244 fig.4 functional diagram. function table note 1. h = high voltage level l = low voltage level x = dont care z = high impedance off-state inputs output n oe na n ny n l l h l h x l h z
december 1990 5 philips semiconductors product speci?cation octal buffer/line driver; 3-state 74hc/hct244 dc characteristics for 74hc for the dc characteristics see 74hc/hct/hcu/hcmos logic family specifications . output capability: bus driver i cc category: msi ac characteristics for 74hc gnd = 0 v; t r =t f = 6 ns; c l =50pf symbol parameter t amb ( c) unit test conditions 74hc v cc (v) waveforms + 25 - 40 to + 85 - 40 to + 125 min. typ. max. min. max. min. max. t phl / t plh propagation delay 1a n to 1y n; 2a n to 2y n 30 11 9 110 22 19 145 28 24 165 33 28 ns 2.0 4.5 6.0 fig.5 t pzh / t pzl 3-state output enable time 1 oe to 1y n; 2 oe to 2y n 36 13 10 150 30 26 190 38 33 225 45 38 ns 2.0 4.5 6.0 fig.6 t phz / t plz 3-state output disable time 1 oe to 1y n; 2 oe to 2y n 39 14 11 150 30 26 190 38 33 225 45 38 ns 2.0 4.5 6.0 fig.6 t thl / t tlh output transition time 14 5 4 60 12 10 75 15 13 90 18 15 ns 2.0 4.5 6.0 fig.5
december 1990 6 philips semiconductors product speci?cation octal buffer/line driver; 3-state 74hc/hct244 dc characteristics for 74hct for the dc characteristics see 74hc/hct/hcu/hcmos logic family specifications . output capability: bus driver i cc category: msi note to hct types the value of additional quiescent supply current ( d i cc ) for a unit load of 1 is given in the family specifications. to determine d i cc per input, multiply this value by the unit load coefficient shown in the table below. ac characteristics for 74hct gnd = 0 v; t r =t f = 6 ns; c l =50pf input unit load coefficient 1a n 2a n 1 oe 2 oe 0.70 0.70 0.70 0.70 symbol parameter t amb ( c) unit test conditions 74hct v cc (v) waveforms + 25 - 40 to + 85 - 40 to + 125 min. typ. max. min. max. min. max. t phl / t plh propagation delay 1a n to 1y n; 2a n to 2y n 13 22 28 33 ns 4.5 fig.5 t pzh / t pzl 3-state output enable time 1 oe to 1y n; 2 oe to 2y n 15 30 38 45 ns 4.5 fig.6 t phz / t plz 3-state output disable time 1 oe to 1y n; 2 oe to 2y n 15 25 31 38 ns 4.5 fig.6 t thl / t tlh output transition time 5 12 15 18 ns 4.5 fig.5
december 1990 7 philips semiconductors product speci?cation octal buffer/line driver; 3-state 74hc/hct244 ac waveforms package outlines see 74hc/hct/hcu/hcmos logic package outlines . fig.5 waveforms showing the input (1a n , 2a n ) to output (1y n , 2y n ) propagation delays and the output transition times. (1) hc : v m = 50%; v i = gnd to v cc . hct : v m = 1.3 v; v i = gnd to 3 v. fig.6 waveforms showing the 3-state enable and disable times. (1) hc : v m = 50%; v i = gnd to v cc . hct : v m = 1.3 v; v i = gnd to 3 v.
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