1/9 july 2001 n high speed: t pd = 10ns (typ.) at v cc =6v n low power dissipation: i cc =4 m a(max.) at t a =25 c n high noise immunity: v nih =v nil =28%v cc (min.) n symmetrical output impedance: |i oh |=i ol = 4ma (min) n balanced propagation delays: t plh @ t phl n wide operating voltage range: v cc (opr) = 2v to 6v n pin and function compatible with 74 series 157 description the m74hc157 is an high speed cmos quad 2 channel multiplexer fabricated with silicon gate c 2 mos technology. these device consist of four 2-input digital multiplexer with common select and strobe inputs. when the strobe input is held high, selection of data is inhibited and all the outputs become low. the select decoding determines whether the a or b inputs get routed to their corresponding y outputs. all inputs are equipped with protection circuits against static discharge and transient excess voltage. m74hc157 quad 2 channel multiplexer pin connection and iec logic symbols order codes package tube t & r dip m74hc157b1r sop m74hc157m1r M74HC157RM13TR tssop m74hc157ttr tssop dip sop
m74hc157 2/9 input and output equivalent circuit pin description truth table x : don't care logic diagram pin no symbol name and function 1 select common data select input 2, 5, 11, 14 1a to 4a data inputs from source a 3, 6, 10, 13 1b to 4b data inputs from source b 4, 7, 9, 12 1y to 4y multiplexer output 15 strobe strobe inputs 8 gnd ground (0v) 16 v cc positive supply voltage inputs outputs strobe select a b y hxxxl lllxl llhxh lhxll lhxhh
m74hc157 3/9 absolute maximum ratings absolute maximum ratings are those values beyond which damage to the device may occur. functional operation under these conditions is not implied (*) 500mw at 65 c; derate to 300mw by 10mw/ c from 65 cto85 c recommended operating conditions symbol parameter value unit v cc supply voltage -0.5 to +7 v v i dc input voltage -0.5 to v cc + 0.5 v v o dc output voltage -0.5 to v cc + 0.5 v i ik dc input diode current 20 ma i ok dc output diode current 20 ma i o dc output current 25 ma i cc or i gnd dc v cc or ground current 50 ma p d power dissipation 500(*) mw t stg storage temperature -65 to +150 c t l lead temperature (10 sec) 300 c symbol parameter value unit v cc supply voltage 2to6 v v i input voltage 0 to v cc v v o output voltage 0 to v cc v t op operating temperature -55 to 125 c t r ,t f input rise and fall time v cc = 2.0v 0 to 1000 ns v cc = 4.5v 0 to 500 ns v cc = 6.0v 0 to 400 ns
m74hc157 4/9 dc specifications * : applicable only to dir, g, g input ac electrical characteristics (c l = 50 pf, input t r =t f = 6ns) symbol parameter test condition value unit v cc (v) t a =25 c -40 to 85 c -55 to 125 c min. typ. max. min. max. min. max. v ih high level input voltage 2.0 1.5 1.5 1.5 v 4.5 3.15 3.15 3.15 6.0 4.2 4.2 4.2 v il low level input voltage 2.0 0.5 0.5 0.5 v 4.5 1.35 1.35 1.35 6.0 1.8 1.8 1.8 v oh high level output voltage 2.0 i o =-20 m a 1.9 2.0 1.9 1.9 v 4.5 i o =-20 m a 4.4 4.5 4.4 4.4 6.0 i o =-20 m a 5.9 6.0 5.9 5.9 4.5 i o =-4.0 ma 4.18 4.31 4.13 4.10 6.0 i o =-5.2 ma 5.68 5.8 5.63 5.60 v ol low level output voltage 2.0 i o =20 m a 0.0 0.1 0.1 0.1 v 4.5 i o =20 m a 0.0 0.1 0.1 0.1 6.0 i o =20 m a 0.0 0.1 0.1 0.1 4.5 i o =4.0 ma 0.17 0.26 0.33 0.40 6.0 i o =5.2 ma 0.18 0.26 0.33 0.40 i i input leakage current 6.0 v i =v cc or gnd 0.1 1 1 m a i cc quiescent supply current 6.0 v i =v cc or gnd 44080 m a symbol parameter test condition value unit v cc (v) t a =25 c -40 to 85 c -55 to 125 c min. typ. max. min. max. min. max. t tlh t thl output transition time 2.0 30 75 95 110 ns 4.5 8151922 6.0 7131619 t plh t phl propagation delay time (a, b - y) 2.0 30 100 125 150 ns 4.5 12 20 25 30 6.0 10 17 21 26 t plh t phl propagation delay time (select - y) 2.0 50 125 155 190 ns 4.5 16 25 31 38 6.0 14 21 26 32 t plh t phl propagation delay time (strobe -y) 2.0 36 115 145 175 ns 4.5 12 23 29 35 6.0 10 20 25 30
m74hc157 5/9 capacitive characteristics 1) c pd is defined as the value of the ic's internal equivalent capacitance which is calculated from the operating current consumption without load. (refer to test circuit). average operating current can be obtained by the following equation. i cc(opr) =c pd xv cc xf in +i cc /4(per chan- nel) test circuit c l = 50pf or equivalent (includes jig and probe capacitance) r t =z out of pulse generator (typically 50 w ) waveform : propagation delay times (f=1mhz; 50% duty cycle) symbol parameter test condition value unit v cc (v) t a =25 c -40 to 85 c -55 to 125 c min. typ. max. min. max. min. max. c in input capacitance 5.0 5101010pf c pd power dissipation capacitance (note 1) 5.0 47 pf
m74hc157 6/9 dim. mm. inch min. typ max. min. typ. max. a1 0.51 0.020 b 0.77 1.65 0.030 0.065 b 0.5 0.020 b1 0.25 0.010 d 20 0.787 e 8.5 0.335 e 2.54 0.100 e3 17.78 0.700 f 7.1 0.280 i 5.1 0.201 l 3.3 0.130 z 1.27 0.050 plastic dip-16 (0.25) mechanical data p001c
m74hc157 7/9 dim. mm. inch min. typ max. min. typ. max. a 1.75 0.068 a1 0.1 0.2 0.003 0.007 a2 1.65 0.064 b 0.35 0.46 0.013 0.018 b1 0.19 0.25 0.007 0.010 c 0.5 0.019 c1 45 (typ.) d 9.8 10 0.385 0.393 e 5.8 6.2 0.228 0.244 e 1.27 0.050 e3 8.89 0.350 f 3.8 4.0 0.149 0.157 g 4.6 5.3 0.181 0.208 l 0.5 1.27 0.019 0.050 m 0.62 0.024 s8 (max.) so-16 mechanical data po13h
m74hc157 8/9 dim. mm. inch min. typ max. min. typ. max. a 1.2 0.047 a1 0.05 0.15 0.002 0.004 0.006 a2 0.8 1 1.05 0.031 0.039 0.041 b 0.19 0.30 0.007 0.012 c 0.09 0.20 0.004 0.0089 d 4.9 5 5.1 0.193 0.197 0.201 e 6.2 6.4 6.6 0.244 0.252 0.260 e1 4.3 4.4 4.48 0.169 0.173 0.176 e 0.65 bsc 0.0256 bsc k0 8 0 8 l 0.45 0.60 0.75 0.018 0.024 0.030 tssop16 mechanical data c e b a2 a e1 d 1 pin 1 identification a1 l k e 0080338d
m74hc157 information furnished is believed to be accurate and reliable. however, stmicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringe ment of patents or other righ ts of third parties which may result from its use. no license is granted by implication or otherwise under any patent or patent rights of stmicroelectronics. specifications mentioned in this pub lication are subject to change without notice. thi s pub lication supersedes and replaces all information previously supplied. stmicroelectronics prod ucts are not authori zed for use as critical components in life suppo rt devices or systems without express written approval of stmicroelectronics. ? the st logo is a registered trademark of stmicroelectronics ? 2001 stmicroelectronics - printed in italy - all rights reserved stmicroelectronics group of companies australia - brazil - china - finland - france - germany - hong kong - india - italy - japan - malaysia - malta - morocco singapore - spain - sweden - swit zerland - united kingdom ? http://w ww.st.com 9/9
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