1 01/10/11 pin description pin name description i a n - i d n data inputs s select inputs e enable y a -y d data outputs gnd ground v cc power nc no connect description pericom semiconductors pi3b3257a is a 3.3 volt, quad 2:1 multiplexer/demultiplexer with three-state outputs that is pinout and function compatible with the pi74fct257t, 74f257, and 74als/as/ls257. inputs can be connected to outputs with low on-resistance (5?) with no additional ground bounce noise or propagation delay. block diagram features ? near -zero propagation delay ? 5? switches connect inputs to outputs ? fast switching speed: 4.8ns max. ? ultra-low quiescent power: 0.1a typical C ideally suited for notebook applications ? pin compatible with 74 series 257 logic devices ? packaging (pb-free & green): C 16-pin 150 mil wide plastic qsop (q) pin confguration note: 1. h = high voltage level l = low voltage level e i a 0 i a 1 i b 0 i b 1 i c 0 i c 1 i d 0 i d 1 s y a y b y c y d i y e sw sw sw sw sw sw sw sw sw truth table (1) e s y a y b y c y d function h x hi-z hi-z hi-z hi-z disable l l i a 0 i b 0 i c 0 i d 0 s = 0 l h i a 1 i b 1 i c 1 i d 1 s = 1 v cc s 1 e i a 0 2 i d 0 i a 1 3 i d 1 y a 4 y d i b 0 5 16 i c 0 i b 1 6 15 i c 1 y b 7 14 y c 8 13 12 gnd 11 10 9 pi3b3257a 3.3v, quad 2:1 mux/demux nanoswitch ? 11-0009
2 01/10/11 pi3b3257a 3.3v, quad 2:1 mux/demux nanoswitch ? notes: 1. this parameter is determined by device characterization but is not production tested. storage temperature ..................................................................... C65c to +150c ambient temperature with power applied .................................... C40c to +85c supply voltage to ground potential ................................................. C0.5v to +4.6v dc input voltage ............................................................................. C0.5v to +4.6v dc output current ........................................................................................ 120ma power dissipation ............................................................................................ 0.5w note: stresses greater than those listed under maximum ratings may cause permanent damage to the device. this is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specifcation is not mplied. exposure to absolute maximum rating conditions for extended periods may af fect reliability. maximum ratings (above which the useful life may be impaired. for user guidelines, not tested.) dc electrical characteristics (over the operating range, t a = C40c to +85c, v cc = 3.3v 10%) parameters description test conditions (1) min. typ. (2) max. units v ih input high voltage guaranteed logic high level 2 v v il input low voltage guaranteed logic low level C0.5 0.8 i ih input high current v cc = max., v in = v cc 1 a i il input low current v cc = max., v in = gnd 1 i ozh high impedance output current 0 in, yn v cc 1 v ik clamp diode voltage v cc = min., i in = C18ma C1.2 v r on switch on-resistance (3) v cc = min., v in = 0.0v, ion = 48ma or 64ma 5 7 ? v cc = min., v in = 2.4v, i on = 15ma 8 17 capacitance (t a = 25c, f = 1 mhz) parameters (1) description test conditions typ. units c in input capacitance v in = 0v 2 pf c offyn y n capacitance, switch off 7.5 c offin i n capacitance, switch off 4.0 c on i n /y n capacitance, switch on 11 notes: 1. for max. or min. conditions, use appropriate value specifed under electrical characteristics for the applicable device type. 2. t ypical values are at v cc = 3.3v, t a = 25c ambient and maximum loading. 3. measured by the voltage drop between i and y pin at indicated current through the switch. on-resistance is determined by the lower of the voltages on the two (i,y) pins. 11-0009
3 01/10/11 pi3b3257a 3.3v, quad 2:1 mux/demux nanoswitch ? notes: 1. for max. or min. conditions, use appropriate value specifed under electrical characteristics for the applicable device. 2. t ypical values are at v cc = 3.3v, +25c ambient. 3. per ttl driven input (control inputs only); i and y pins do not contribute to i cc . 4. this current applies to the control inputs only and represent the current required to switch internal capacitance at the specifed frequency . the i and y inputs generate no signifcant ac or dc currents as they transition. this parameter is not tested, but is guaranteed by design. notes: 1. this parameter is guaranteed but not tested on propagation delays. 2. the bus switch contributes no propagational delay other than the rc delay of the on-resistance of the switch and the load capacitance. the switchs time constant alone is of the order of 0.25ns for 50pf load. since this time constant is much smaller than the rise/fall times of typical driving signals, it adds very little propagational delay to the system. propagational delay of the bus switch when used in a system is determined by the driving circuit on the driving side of the switch and its interaction with the load on the driven side. power supply characteristics parameters description test conditions (1) min. typ. (2) max. units i cc quiescent power supply current v cc = max. v in = gnd or v cc 0.1 3.0 a ?i cc supply current per input @ ttl high (3, 4) v cc = max. v in = 3.0 750 switching characteristics over operating range parameters description conditions com. units min. max. t iy propagation delay in to yn (1,2) c l = 50pf r l = 500? 0.25 ns t sy bus select time, sn to yn 1 4.5 t pzh t pzl bus enable time, e to yn 1 4.5 t phz t plz bus disable time, e to yn 1 4.8 applications information logic inputs the logic control inputs can be driven up to +3.6v regardless of the supply voltage. for example, given a + 3.3v supply, in may be driven low to 0v and high to 3.6v. driving in rail-to-rail? minimizes power consumption. power-supply sequencing and hot-plug information proper power-supply sequencing is recommended for all cmos devices. always apply v cc and gnd before applying signals to input/output or control pins. rail-to-rail is a registeredtrademark of nippon motorola, ltd. 11-0009
4 01/10/11 pi3b3257a 3.3v, quad 2:1 mux/demux nanoswitch ? ordering information ordering code packaging code package description pi3b3257aqe q pb-free & green, 16-pin 150 mil wide plastic qsop notes: ? thermal characteristics can be found on the company web site at www .pericom.com/packaging/ ? e = pb-free & green ? adding an x suffx = tape/reel pericom semiconductor corporation ? 1-800-435-2336 ? www .pericom.com .189 .197 .053 .069 .004 .010 seating plane .025 bsc .007 .010 .228 .244 1 16 .150 .157 .016 .050 x.xx x.xx denotes dimensions in millimeters 0.635 4.80 5.00 1.35 1.75 5.79 6.19 0.101 0.254 .008 .012 0.203 0.305 3.81 3.99 0.178 0.254 0.38 0.41 1.27 .008 0.203 .015 x 45 ref detail a detail a .008 0.20 min. guage plane .010 0.254 .041 1.04 ref .016 .035 0.41 0.89 0?-6? .008 .013 0.20 0.33 packaging mechanical: 16-pin qsop (q) 11-0009
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