? 2001 fairchild semiconductor corporation ds500107 www.fairchildsemi.com february 1994 revised february 2001 74lcx244 low voltage buffer/line driver with 5v tolerant inputs and outputs 74lcx244 low voltage buffer/line driver with 5v tolerant inputs and outputs general description the lcx244 contains eight non-inverting buffers with 3-state outputs. the device may be employed as a mem- ory address driver, clock driver and bus-oriented transmit- ter/receiver. the lcx244 is designed for low voltage (2.5v or 3.3v) v cc applications with capability of interfacing to a 5v signal environment. the lcx244 is fabricated with an advanced cmos tech- nology to achieve high speed operation while maintaining cmos low power dissipation. features 5v tolerant inputs and outputs 2.3v?3.6v v cc specifications provided 6.5 ns t pd max (v cc = 3.3v), 10 a i cc max power down high impedance inputs and outputs supports live insertion/withdrawal (note 1) 24 ma output drive (v cc = 3.0v) implements patented noise/emi reduction circuitry latch-up performance exceeds 500 ma esd performance: human body model > 2000v machine model > 200v note 1: to ensure the high-impedance state during power up or down, oe should be tied to v cc through a pull-up resistor: the minimum value or the resistor is determined by the current-sourcing capability of the driver. ordering code: devices also available in tape and reel. specify by appending the suffix letter ? x ? to the ordering code. logic symbol ieee/iec connection diagram order number package number package description 74lcx244wm m20b 20-lead small outline integrated circuit (soic), jedec ms-013, 0.300" wide 74lcx244sj m20d 20-lead small outline package (sop), eiaj type ii, 5.3mm wide 74lcx244msa msa20 20-lead shrink small outline package (ssop), eiaj type ii, 5.3mm wide 74lcx244mtc mtc20 20-lead thin shrink small outline package (tssop), jedec mo-153, 4.4mm wide
www.fairchildsemi.com 2 74lcx244 pin descriptions truth tables h = high voltage level l = low voltage level x = immaterial z = high impedance pin names description oe 1 , oe 2 3-state output enable inputs i 0 ? i 7 inputs o 0 ? o 7 outputs inputs outputs oe 1 i n (pins 12, 14, 16, 18) ll l lh h hx z inputs outputs oe 2 i n (pins 3, 5, 7, 9) ll l lh h hx z
3 www.fairchildsemi.com 74lcx244 absolute maximum ratings (note 2) recommended operating conditions (note 4) note 2: the absolute maximum ratings are those values beyond which the safety of the device cannot be guaranteed. the device should not be operated at these limits. the parametric values defined in the electrical characteristics tables are not guaranteed at the absolute maxi mum ratings. the ? recom- mended operating conditions ? table will define the conditions for actual device operation. note 3: i o absolute maximum rating must be observed. note 4: unused inputs or i/os must be held high or low. they may not float. dc electrical characteristics symbol parameter value conditions units v cc supply voltage ? 0.5 to + 7.0 v v i dc input voltage ? 0.5 to + 7.0 v v o dc output voltage ? 0.5 to + 7.0 output in 3-state v ? 0.5 to v cc + 0.5 output in high or low state (note 3) i ik dc input diode current ? 50 v i < gnd ma i ok dc output diode current ? 50 v o < gnd ma + 50 v o > v cc i o dc output source/sink current 50 ma i cc dc supply current per supply pin 100 ma i gnd dc ground current per ground pin 100 ma t stg storage temperature ? 65 to + 150 c symbol parameter min max units v cc supply voltage operating 2.0 3.6 v data retention 1.5 3.6 v i input voltage 0 5.5 v v o output voltage high or low state 0 v cc v 3-state 0 5.5 i oh /i ol output current v cc = 3.0v ? 3.6v 24 ma v cc = 2.7v ? 3.0v 12 v cc = 2.3v ? 2.7v 8 t a free-air operating temperature ? 40 85 c ? t/ ? v input edge rate, v in = 0.8v ? 2.0v, v cc = 3.0v 0 10 ns/v symbol parameter conditions v cc t a = ? 40 c to + 85 c units (v) min max v ih high level input voltage 2.3 ? 2.7 1.7 v 2.7 ? 3.6 2.0 v il low level input voltage 2.3 ? 2.7 0.7 v 2.7 ? 3.6 0.8 v oh high level output voltage i oh = ? 100 a2.3 ? 3.6 v cc ? 0.2 v i oh = ? 8 ma 2.3 1.8 i oh = ? 12 ma 2.7 2.2 i oh = ? 18 ma 3.0 2.4 i oh = ? 24 ma 3.0 2.2 v ol low level output voltage i ol = 100 a2.3 ? 3.6 0.2 v i ol = 8 ma 2.3 0.6 i ol = 12 ma 2.7 0.4 i ol = 16 ma 3.0 0.4 i ol = 24 ma 3.0 0.55 i i input leakage current 0 v i 5.5v 2.3 ? 3.6 5.0 a i oz 3-state output leakage 0 v o 5.5v 2.3 ? 3.6 5.0 a v i = v ih or v il i off power-off leakage current v i or v o = 5.5v 0 10 a
www.fairchildsemi.com 4 74lcx244 dc electrical characteristics (continued) note 5: outputs disabled or 3-state only. ac electrical characteristics note 6: skew is defined as the absolute value of the difference between the actual propagation delay for any two separate outputs of th e same device. the specification applies to any outputs switching in the same direction, either high-to-low (t oshl ) or low-to-high (t oslh ). dynamic switching characteristics capacitance symbol parameter conditions v cc t a = ? 40 c to + 85 c units (v) min max i cc quiescent supply current v i = v cc or gnd 2.3 ? 3.6 10 a 3.6v v i , v o 5.5v (note 5) 2.3 ? 3.6 10 ? i cc increase in i cc per input v ih = v cc ? 0.6v 2.3 ? 3.6 500 a symbol parameter t a = ? 40 c to + 85 c, r l = 500 ? units v cc = 3.3v 0.3v v cc = 2.7v v cc = 2.5v 0.2 c l = 50 pf c l = 50 pf c l = 30 pf min max min max min max t phl propagation delay 1.5 6.5 1.5 7.5 1.5 7.8 ns t plh data to output 1.5 6.5 1.5 7.5 1.5 7.8 t pzl output enable time 1.5 8.0 1.5 9.0 1.5 10.0 ns t pzh 1.5 8.0 1.5 9.0 1.5 10.0 t plz output disable time 1.5 7.0 1.5 8.0 1.5 8.4 ns t phz 1.57.01.58.01.58.4 t oshl output to output skew (note 6) 1.0 ns t oslh 1.0 symbol parameter conditions v cc t a = 25 c units (v) typical v olp quiet output dynamic peak v ol c l = 50 pf, v ih = 3.3v, v il = 0v 3.3 0.8 v c l = 30 pf, v ih = 2.5v, v il = 0v 2.5 0.6 v olv quiet output dynamic valley v ol c l = 50 pf, v ih = 3.3v, v il = 0v 3.3 ? 0.8 v c l = 30 pf, v ih = 2.5v, v il = 0v 2.5 ? 0.6 symbol parameter conditions typical units c in input capacitance v cc = open, v i = 0v or v cc 7pf c out output capacitance v cc = 3.3v, v i = 0v or v cc 8pf c pd power dissipation capacitance v cc = 3.3v, v i = 0v or v cc , f = 10 mhz 25 pf
5 www.fairchildsemi.com 74lcx244 ac loading and waveforms generic for lcx family figure 1. ac test circuit (c l includes probe and jig capacitance) waveform for inverting and non-inverting functions propagation delay. pulse width and t rec waveforms 3-state output low enable and disable times for logic 3-state output high enable and disable times for logic setup time, hold time and recovery time for logic t rise and t fall figure 2. waveforms (input characteristics; f =1mhz, t r = t f = 3ns) test switch t plh , t phl open t pzl , t plz 6v at v cc = 3.3 0.3v v cc x 2 at v cc = 2.5 0.2v t pzh ,t phz gnd symbol v cc 3.3v 0.3v 2.7v 2.5v 0.2v v mi 1.5v 1.5v v cc /2 v mo 1.5v 1.5v v cc /2 v x v ol + 0.3v v ol + 0.3v v ol + 0.15v v y v oh ? 0.3v v oh ? 0.3v v oh ? 0.15v
www.fairchildsemi.com 6 74lcx244 schematic diagram generic for lcx family figure 3.
7 www.fairchildsemi.com 74lcx244 physical dimensions inches (millimeters) unless otherwise noted 20-lead small outline integrated circuit (soic), jedec ms-013, 0.300" wide package number m20b
www.fairchildsemi.com 8 74lcx244 physical dimensions inches (millimeters) unless otherwise noted (continued) 20-lead small outline package (sop), eiaj type ii, 5.3mm wide package number m20d
9 www.fairchildsemi.com 74lcx244 physical dimensions inches (millimeters) unless otherwise noted (continued) 20-lead shrink small outline package (ssop), eiaj type ii, 5.3mm wide package number msa20
www.fairchildsemi.com 10 74lcx244 low voltage buffer/line driver with 5v tolerant inputs and outputs physical dimensions inches (millimeters) unless otherwise noted (continued) 20-lead thin shrink small outline package (tssop), jedec mo-153, 4.4mm wide package number mtc20 fairchild does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and fairchild reserves the right at any time without notice to change said circuitry and specifications. life support policy fairchild ? s products are not authorized for use as critical components in life support devices or systems without the express written approval of the president of fairchild semiconductor corporation. as used herein: 1. life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and (c) whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be rea- sonably expected to result in a significant injury to the user. 2. a critical component in any component of a life support device or system whose failure to perform can be rea- sonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. www.fairchildsemi.com
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