74VHC157 quad 2 channel multiplexer preliminary data october 1998 n high speed: t pd = 4.1 ns (typ.) at v cc =5v n low power dissipation: i cc =4 m a (max.) at t a =25 o c n high noise immunity: v nih =v nil =28%v cc (min.) n power down protection on inputs n symmetrical output impedance: |i oh |=i ol = 8 ma (min) n balanced propagation delays: t plh @ t phl n operating voltage range: v cc (opr) = 2v to 5.5v n pin and function compatible with 74 series 157 n improved latch-up immunity n low noise: v olp = 0.8v (max.) description the 74VHC157 is an high-speed cmos quad 2-channel multiplexer fabricated with sub-micron silicon gate and double-layer metal wiring c 2 mos technology. it has similar high speed performance of equivalent bipolar schottky ttl combined with true cmos low power dissipation. it consists of four 2-input digital multiplexers with common select and strobe inputs. it is a non-inverting multiplexer. 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. power down protection is provided on all inputs and 0 to 7v can be accepted on inputs with no regard to the supply voltage. this device can be used to interface 5v to 3v.all inputs and outputs are equipped with protection circuits against static discharge, giving them 2kv esd immunity and transient excess voltage. pin connection and iec logic symbols m1 (micro package) t (tssop package) order codes : 74VHC157m 74VHC157t ? 1/9
input equivalent circuit truth table input output strobe select a b y hxxxl lllxl llhxh lhxll lhxhh x:oho or olo pin description 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 outputs 15 strobe strobe input 8 gnd ground (0v) 16 v cc positive supply voltage logic diagram 74VHC157 2/9
absolute maximum ratings symbol parameter value unit 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 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 t stg storage temperature -65 to +150 o c t l lead temperature (10 sec) 300 o c absolute maximum ratings are those values beyond which damage to the device may occur. functional operation under these condition is not implied. recommended operating conditions symbol parameter value unit v cc supply voltage 2.0 to 5.5 v v i input voltage 0 to 5.5 v v o output voltage 0 to v cc v t op operating temperature -40 to +85 o c dt/dv input rise and fall time (see note 1) (v cc =3.3 0.3v) (v cc =5.0 0.5v) 0to100 0to20 ns/v ns/v 1) v in from 30% to70%of v cc dc specifications symbol parameter test conditions value unit v cc (v) t a =25 o c -40 to 85 o c min. typ. max. min. max. v ih high level input voltage 2.0 1.5 1.5 v 3.0 to 5.5 0.7v cc 0.7v cc v il low level input voltage 2.0 0.5 0.5 v 3.0 to 5.5 0.3v cc 0.3v cc v oh high level output voltage 2.0 v i (*) = v ih or v il i o =-50 m a1.9 2.0 1.9 v 3.0 i o =-50 m a2.9 3.0 2.9 4.5 i o =-50 m a4.4 4.5 4.4 3.0 i o =-4 ma 2.58 2.48 4.5 i o =-8 ma 3.94 3.8 v ol low level output voltage 2.0 v i (*) = v ih or v il i o =50 m a 0.0 0.1 0.1 v 3.0 i o =50 m a 0.0 0.1 0.1 4.5 i o =50 m a 0.0 0.1 0.1 3.0 i o =4 ma 0.36 0.44 4.5 i o =8 ma 0.36 0.44 i i input leakage current 0 to 5.5 v i =5.5vorgnd 0.1 1.0 m a i cc quiescent supply current 5.5 v i =v cc orgnd 4 40 m a (*) all outputs loaded. 74VHC157 3/9
capacitive characteristics symbol parameter test conditions value unit t a =25 o c -40 to 85 o c min. typ. max. min. max. c in input capacitance 4 10 10 pf c pd power dissipation capacitance (note 1) 20 pf 1) c pd isdefined as the value of the ic'sinternal equivalent capacitance which is calculated fromthe operating current consumption without load. (refert o test circuit).average operating current can be obtained by the following equation. i cc (opr) = c pd ? v cc ? f in +i cc /4 (per channel) ac electrical characteristics (input t r =t f =3 ns) symbol parameter test condition value unit v cc (v) c l (pf) t a =25 o c -40 to 85 o c min. typ. max. min. max. t plh t phl propagation delay time a, b to y 3.3 (*) 15 6.2 9.7 1.0 11.5 ns 3.3 (*) 50 8.7 13.2 1.0 15.0 5.0 (**) 15 4.1 6.4 1.0 7.5 5.0 (**) 50 5.6 8.4 1.0 9.5 t plh t phl propagation delay time select to y 3.3 (*) 15 8.4 13.2 1.0 15.5 ns 3.3 (*) 50 10.9 16.7 1.0 19.0 5.0 (**) 15 5.3 8.1 1.0 9.5 5.0 (**) 50 6.8 10.1 1.0 11.5 t plh t phl propagation delay time strobe to y 3.3 (*) 15 8.7 13.6 1.0 16.0 ns 3.3 (*) 50 11.2 17.1 1.0 19.5 5.0 (**) 15 5.6 8.6 1.0 10.0 5.0 (**) 50 7.1 10.6 1.0 12.0 (*) voltage range is 3.3v 0.3v (**) voltage range is 5v 0.5v 74VHC157 4/9
dynamic switching characteristics symbol parameter test conditions value unit v cc (v) t a =25 o c -40 to 85 o c min. typ. max. min. max. v olp dynamic low voltage quiet output (note 1, 2) 5.0 c l =50pf 0.3 0.8 v v olv -0.8 -0.3 v ihd dynamic high voltage input (note 1, 3) 5.0 3.5 v ild dynamic low voltage input (note 1, 3) 5.0 1.5 1) worst case package. 2) max number of outputs defined as (n). data inputs are driven 0v to 5.0v, (n -1) outputs switching and one output at gnd. 3) max number of data inputs (n) switching. (n-1) switching 0v to5.0v. inputs under test switching: 5.0v to threshold (v ild ), 0v to threshold (v ihd ), f=1mhz. test circuit c l = 15/50 pf or equivalent (includes jig and probe capacitance) r t =z out of pulse generator (typically 50 w ) 74VHC157 5/9
waveform 1: propagation delays for inverting conditions waveform 2: propagation delays for non-inverting conditions 74VHC157 6/9
dim. mm inch min. typ. max. min. typ. max. a 1.75 0.068 a1 0.1 0.2 0.004 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 s 8 (max.) p013h so-16 mechanical data 74VHC157 7/9
dim. mm inch min. typ. max. min. typ. max. a 1.1 0.433 a1 0.05 0.10 0.15 0.002 0.004 0.006 a2 0.85 0.9 0.95 0.335 0.354 0.374 b 0.19 0.30 0.0075 0.0118 c 0.09 0.20 0.0035 0.0079 d 4.9 5 5.1 0.193 0.197 0.201 e 6.25 6.4 6.5 0.246 0.252 0.256 e1 4.3 4.4 4.48 0.169 0.173 0.176 e 0.65 bsc 0.0256 bsc k0 o 4 o 8 o 0 o 4 o 8 o l 0.50 0.60 0.70 0.020 0.024 0.028 c e b a2 a e1 d 1 pin 1 identification a1 l k e tssop16 mechanical data 74VHC157 8/9
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 infringement of patents or other rights 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. specification mentioned in this publication are subject to change without notice. this publication supersedes and replaces all information previously supplied. stmicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of stmicroelectronics. the st logo is a registered trademark of stmicroelectronics ? 1998 stmicroelectronics printed in italy all rights reserved stmicroelectronics group of companies australia - brazil - canada - china - france - germany - italy - japan - korea - malaysia - malta - mexico - morocco - the netherlands - singapore - spain - sweden - switzerland - taiwan - thailand - united kingdom - u.s.a. http://www.st.com . 74VHC157 9/9
|
