tm dm74als257, dm74als258 3-state quad 1-of-2-line data selector/multiplexer may 2007 ?984 fairchild semiconductor corporation www.fairchildsemi.com dm74als257, dm74als258 rev. 1.2 dm74als257, dm74als258 3-state quad 1-of-2-line data selector/multiplexer features switching specifications at 50pf switching specifications guaranteed over full temperature and v cc range advanced oxide-isolated, ion-implanted schottky ttl process functionally and pin for pin compatible with schottky and low power schottky ttl counterpart improved ac performance over schottky and low power schottky counterparts 3-state buffer-type outputs drive bus lines directly expand any data input point multiplex dual data buses general four functions of two variables (one variable is common) source programmable counters general description these data selectors/multiplexers contain inverters and drivers to supply full on-chip data selection to the four 3-state outputs that can interface directly with data lines of bus-organized systems. a 4-bit word selected from one of two sources is routed to the four outputs. the dm74als257 presents true data whereas the dm74als258 presents inverted data to minimize propa- gation delay time. this 3-state output feature means that n-bit (paral- leled) data selectors with up to 258 sources can be implemented for data buses. it also permits the use of standard ttl registers for data retention throughout the system. ordering information devices also available in tape and reel. specify by appending the suffix letter ??to the ordering number. order number package number package description dm74als257m m16a 16-lead small outline integrated circuit (soic), jedec ms-012, 0.150" narrow dm74als257sj m16d 16-lead small outline package (sop), eiaj type ii, 5.3mm wide dm74als258m m16a 16-lead small outline integrated circuit (soic), jedec ms-012, 0.150" narrow
dm74als257, dm74als258 3-state quad 1-of-2-line data selector/multiplexer ?984 fairchild semiconductor corporation www.fairchildsemi.com dm74als257, dm74als258 rev. 1.2 2 connection diagram function table h = high level l = low level x = don't care z = high impedance (off) inputs output y output control select a b dm74als257 dm74als258 hxxxz z lllxl h llhxh l lhxll h lhxhh l
dm74als257, dm74als258 3-state quad 1-of-2-line data selector/multiplexer ?984 fairchild semiconductor corporation www.fairchildsemi.com dm74als257, dm74als258 rev. 1.2 3 logic diagrams dm74als257 dm74als258
dm74als257, dm74als258 3-state quad 1-of-2-line data selector/multiplexer ?984 fairchild semiconductor corporation www.fairchildsemi.com dm74als257, dm74als258 rev. 1.2 4 absolute maximum ratings stresses exceeding the absolute maximum ratings may damage the device. the device may not function or be operable above the recommended operating conditions and stressing the parts to these levels is not recommended. in addition, extended exposure to stresses above the recommended operating conditions may affect device reliability. the absolute maximum ratings are stress ratings only. recommended operating conditions the recommended operating conditions table defines the conditions for actual device operation. recommended operating conditions are specified to ensure optimal performance to the datasheet specifications. fairchild does not recommend exceeding them or designing to absolute maximum ratings. symbol parameter rating v cc supply voltage 7v v i input voltage 7v v oltage applied to disabled output 5.5v t a operating free air temperature range 0? to +70? t stg storage temperature range ?5? to +150? ja t ypical thermal resistance 102.0?/w symbol parameter min. nom. max. units v cc supply voltage 4.5 5 5.5 v v ih high level input voltage 2 v v il low level input voltage 0.8 v i oh high level output current ?.6 ma i ol low level output current 24 ma t a f ree air operating temperature 0 70 c
dm74als257, dm74als258 3-state quad 1-of-2-line data selector/multiplexer ?984 fairchild semiconductor corporation www.fairchildsemi.com dm74als257, dm74als258 rev. 1.2 5 electrical characteristics over recommended operating free air temperature range. all typical values are measured at v cc = 5v, t a = 25?. symbol parameter conditions min. typ. max. units v ik input clamp voltage v cc = 4.5v, i i = ?8ma ?.5 v v oh high level output voltage v cc = 4.5v i oh = ?.6ma 2.4 3.3 v i oh = ?.4ma v cc ?2 v ol low level output voltage v cc = 4.5v i ol = 12ma 0.25 0.4 v i ol = 24ma 0.35 0.5 i i input current at maximum input v oltage v cc = 5.5v, v ih = 7v 0.1 ma i ih high level input current v cc = 5.5v, v ih = 2.7v 20 ? i il low level input current v cc = 5.5v, v il = 0.4v ?.1 ma i o output drive current v cc = 5.5v, v o = 2.25v ?0 ?12 ma i ozh off-state output current, high level voltage applied v cc = 5.5v, v o = 2.7v 20 ? i ozl off-state output current, low level voltage applied v cc = 5.5v, v o = 0.4v ?0 ? i cch supply current dm74als257 v cc = 5.5v, outputs open outputs high 3 6 ma dm74als258 2.5 4 i ccl supply current dm74als257 outputs low 8 12 ma dm74als258 7 11 i ccz supply current dm74als257 outputs disabled 9 14 ma dm74als258 8 13
dm74als257, dm74als258 3-state quad 1-of-2-line data selector/multiplexer ?984 fairchild semiconductor corporation www.fairchildsemi.com dm74als257, dm74als258 rev. 1.2 6 switching characteristics dm74als257 over recommended operating free air temperature range. switching characteristics dm74als258 over recommended operating free air temperature range. symbol parameter conditions from to min. max. units t plh propagation delay time, low-to-high level output v cc = 4.5v to 5.5v, c l = 50pf, r l = 500 ? data any y 2 10 ns t phl propagation delay time, high-to-low level output data any y 2 12 ns t plh propagation delay time, low-to-high level output select any y 4 18 ns t phl propagation delay time, high-to-low level output select any y 5 22 ns t zh output enable time to high level output control any y 4 16 ns t zl output enable time to low level output control any y 5 18 ns t hz output disable time from high level output control any y 2 10 ns t lz output disable time from low level output control any y 3 15 ns symbol parameter conditions from to min. max. units t plh propagation delay time, low-to-high level output v cc = 4.5v to 5.5v, c l = 50pf, r l = 500 ? data any y 2 8 ns t phl propagation delay time, high-to-low level output data any y 2 7 ns t plh propagation delay time, low-to-high level output select any y 3 20 ns t phl propagation delay time, high-to-low level output select any y 5 25 ns t zh output enable time to high level output control any y 5 18 ns t zl output enable time to low level output control any y 5 18 ns t hz output disable time from high level output control any y 2 10 ns t lz output disable time from low level output control any y 3 18 ns
dm74als257, dm74als258 3-state quad 1-of-2-line data selector/multiplexer ?984 fairchild semiconductor corporation www.fairchildsemi.com dm74als257, dm74als258 rev. 1.2 7 physical dimensions dimensions are in millimeters unless otherwise noted. figure 1. 16-lead small outline integrated circuit (soic), jedec ms-012, 0.150" narrow pa ck ag e number m16a
dm74als257, dm74als258 3-state quad 1-of-2-line data selector/multiplexer ?984 fairchild semiconductor corporation www.fairchildsemi.com dm74als257, dm74als258 rev. 1.2 8 physical dimensions (continued) dimensions are in millimeters unless otherwise noted. figure 2. 16-lead small outline package (sop), eiaj type ii, 5.3mm wide pa ck ag e number m16d
dm74als257, dm74als258 3-state quad 1-of-2-line data selector/multiplexer ?984 fairchild semiconductor corporation www.fairchildsemi.com dm74als257, dm74als258 rev. 1.2 9 rev. i28 trademarks the following are registered and unregistered trademarks and service marks fairchild semiconductor owns or is authorized to use and is not intended to be an exhaustive list of all such trademarks disclaimer fairchild semiconductor reserves the right to make changes without further notice to any products herein to improve reliability, function, or design. fairchild does not assume any liability arising out of the application or use of any product or circuit described herein; neither does it convey any license under its patent rights, nor the rights of others. these specifications do not expand the terms of fairchild? worldwide terms and conditions, specifically the warranty therein, which covers these products. life support policy fairchild? products are not authorized for use as critical components in life support devices or systems without the express written approval 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 reasonably expected to result in significant injury to the user. 2. a critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. product status definitions definition of terms acex build it now coreplus crossvolt ctl current transfer logic ecospark fact quiet series fact fast fastvcore fps frfet global power resource sm green fps green fps e-series gto i-lo intellimax isoplanar megabuck microcoupler micropak motion-spm optologic optoplanar pdp-spm power220 power247 poweredge power-spm powertrench programmable active droop qfet qs qt optoelectronics quiet series rapidconfigure smart start spm stealth superfet supersot -3 supersot -6 supersot -8 syncfet the power franchise tinyboost tinybuck tinylogic tinyopto tinypower tinypwm tinywire serdes uhc unifet vcx datasheet identi?ation product status de?ition advance information formative or in design this datasheet contains the design speci?ations for product development. speci?ations may change in any manner without notice. preliminary first production this datasheet contains preliminary data; supplementary data will be published at a later date. fairchild semiconductor reserves the right to make changes at any time without notice to improve design. no identi?ation needed full production this datasheet contains ?al speci?ations. fairchild semiconductor reserves the right to make changes at any time without notice to improve design. obsolete not in production this datasheet contains speci?ations on a product that has been discontinued by fairchild semiconductor. the datasheet is printed for reference information only.
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