1 ps8357c 05 /17/00 1234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121234567890123456789012345678901 2123456789012 1 2345678901234567890123456789012123456789012345678901234567890121234567890123456789012345678901212345678901234567890123456789012 12345678901 2 1234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121234567890123456789012345678901 2123456789012 function be x a 19-a0 disconnect h hi-z connect l b 19-b0 truth table (1) notes: 1. h = high voltage level l = low voltage level hi-z = high impedance pin name description bex bus enable inputs (active low) a 19-a0 bus a b 19-b0 bus b product pin description product pin configuration pi5c16861c pi5c162861c (25 w w w w w ) 20-bit, 2-port bus switch product features near-zero propagation delay 5 w or 25w switches connect inputs to outputs direct bus connection when switches are on 32x384 function with flow through pinout make board layout easier ultra-low quiescent power (105a typical) C ideally suited for notebook applications industrial operating temperature: C40c to +85c packages available: C 48-pin 240-mil wide plastic tssop (a) C 48-pin 300-mil wide plastic ssop (v) product description pericom semiconductors pi5c series of bus switch circuits are produced using the companys advanced submicron cmos technology, achieving industry leading speed. the pi5c16861c is configured as a 20-bit, 2-port bus switch designed with a low on resistance (5 w ) allowing inputs to be connected directly to outputs. the bus switch creates no additional propagational delay or additional ground bounce noise. the switches are turned on by the bus enable (bex) input signal. the pi5c162861c device has a built-in 25-ohm series resistor to reduce noise resulting from reflections, thus eliminating the need for an external terminating resistor. logic block diagram be 1 a 9 a 0 b 9 b 0 be 2 a 19 a 10 b 19 b 10 nc a 0 a 1 a 2 a 3 a 4 a 5 a 6 a 7 a 8 a 9 gnd nc a 10 a 11 a 12 a 13 a 14 a 15 a 16 a 17 a 18 a 19 gnd 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 vcc be 1 b 0 b 1 b 2 b 3 b 4 b 5 b 6 b 7 b 8 b 9 vcc be 2 b 10 b 11 b 12 b 13 b 14 b 15 b 16 b 17 b 18 b 19 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 48-pin a,v
pi5c16861c/162861c 20-bit, 2-port bus switch 2 ps8357c 05 /17/00 1234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121234567890123456789012345678901 2123456789012 1234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121234567890123456789012345678901 2123456789012 dc electrical characteristics (over the operating range, t a = C40c to +85c, v cc = 5v 10%) parameters description test conditions (1) min. typ. (2) max. units v ih input high voltage guaranteed logic high level 2.0 v v il input low voltage guaranteed logic low level C0.5 0.8 v i ih input high current v cc = max., v in = v cc 1a i il input low current v cc = max., v in = gnd 1 a i ozh high impedance output current 0 a, b v cc 1a v ik clamp diode voltage v cc = min., i in = C18ma C1.8 v i os short circuit current (3) a (b) = 0v, b (a) = v cc 100 ma v h input hysteresis at control pins 150 mv r on switch on resistance (4) v cc = min., v in = 0.0v, 16861c 5 9 w i on = 48ma 162861c 20 28 40 v cc = min., v in = 2.4v, 16861c 10 15 w i on = 15ma 162861c 20 35 48 maximum ratings (above which the useful life may be impaired. for user guidelines, not tested.) 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 condi- tions above those indicated in the operational sec- tions of this specification is not implied. exposure to absolute maximum rating conditions for extended periods may affect reliability. capacitance (t a = 25c, f = 1 mhz) parameters (5) description test conditions typ. units c in input capacitance v in = 0v 6 pf c off a/b capacitance, switch off v in = 0v 6 pf c on a/b capacitance, switch on v in = 0v 8 pf notes: 1. for max. or min. conditions, use appropriate value specified under electrical characteristics for the applicable device type. 2. typical values are at v cc = 5.0v, t a = 25c ambient and maximum loading. 3. not more than one output should be shorted at one time. duration of the test should not exceed one second. 4. measured by the voltage drop between a and b pin at indicated current through the switch. on resistance is determined by the lower of the voltages on the two (a,b) pins. 5. 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 (inputs & vcc only) .... C0.5v to +7.0v supply voltage to ground potential (outputs & d/o only) . C0.5v to +7.0v dc input voltage ................................................................... C0.5v to +7.0v dc output current ............................................................................... 120ma power dissipation .................................................................................... 0.5w
pi5c16861c/162861c 20-bit, 2-port bus switch 3 ps8357c 05 /17/00 1234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121234567890123456789012345678901 2123456789012 power supply characteristics parameters description test conditions (1) min. typ. (2) max. units i cc quiescent power v cc = max. v in = gnd or v cc 105 200 a supply current d i cc supply current per v cc = max. v in = 3.4v (3) 2.5 ma input @ ttl high i ccd supply current per v cc = max., 0.25 ma/ input per mhz (4) a and b pins open mhz be x = gnd control input toggling 50% duty cycle notes: 1. for max. or min. conditions, use appropriate value specified under electrical characteristics for the applicable device. 2. typical values are at v cc = 5.0v, +25c ambient. 3. per ttl driven input (v in = 3.4v, control inputs only); a and b 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 specified frequency. the a and b inputs generate no significant ac or dc currents as they transition. this parameter is not tested, but is guaranteed by design. notes: 1. see test circuit and waveforms. 2. this parameter is guaranteed but not tested on propagation delays. 3. the bus switch contributes no propagational delay other than the rc delay of the on resistance of the switch and the load capacitance. the time constant for the switch 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. pi5c16861 switching characteristics over operating range pi5c16861c com. parameters description conditions (1) min. max. units t plh propagation delay (2,3) c l = 50pf 0.25 t phl ax to bx, bx to ax r l = 500 w t pzh bus enable time 1.5 6.5 ns t pzl be x to ax or bx t phz bus disable time 1.5 5.5 t plz bex to ax or bx pi5c162861 switching characteristics over operating range pi5c162861c com. parameters description conditions (1) min. max. units t plh propagation delay (2,3) c l = 50pf 1.25 t phl ax to bx, bx to ax r l = 500 w t pzh bus enable time 1.5 6.5 ns t pzl be x to ax or bx t phz bus disable time 1.5 5.5 t plz bex to ax or bx
pi5c16861c/162861c 20-bit, 2-port bus switch 4 ps8357c 05 /17/00 1234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121234567890123456789012345678901 2123456789012 1234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121234567890123456789012345678901 2123456789012 applications information logic inputs the logic control inputs can be driven up to +5.5v regardless of the supply voltage. for example, given a 5.0v supply, the cont rol or select pins may be driven low to 0v and high to 5.5v. driving the control or select pins rail-torail minimizes power consump tion. r power -supply sequencing proper power-supply sequencing is recommended for all cmos devices. always apply vcc before applying signals to the input/output or control pins. t r a pe g a k c a p - n i pe r u t a r e p m e t a c 1 6 8 6 1 c 5 i p) l ( p o s s t 8 4c 5 8 + o t c 0 4 ? v c 1 6 8 6 1 c 5 i p) v ( p o s s 8 4c 5 8 + o t c 0 4 ? ordering information .236 .244 .488 .496 .002 .006 seating plane .007 .010 .0197 bsc .004 .008 .319 1 48 12.4 12.6 6.0 6.2 0.50 0.17 0.27 8.1 0.05 0.15 0.09 0.20 x.xx x.xx denotes dimensions in millimeters .018 .030 0.45 0.75 .047 1.20 max bsc 48 -tssop (l) package mechanicals
pi5c16861c/162861c 20-bit, 2-port bus switch 5 ps8357c 05 /17/00 1234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121234567890123456789012345678901 2123456789012 0.20 0.51 1.01 0.25 0.381 0.635 .008 .008 .016 0-8? 0.20 0.40 .110 2.79 .010 gauge plane .02 .04 .015 .025 x 45? .025 bsc 0.635 .291 .299 x.xx x.xx denotes dimensions in millimeters 7.39 7.59 .395 .420 10.03 10.67 .620 .630 15.75 16.00 .008 .0135 0.20 0.34 1 48 nom. max 48 -tssop (v) package mechanicals pericom semiconductor corporation 2380 bering drive ? san jose, ca 95131 ? 1-800-435-2336 ? fax (408) 435-1100 ? http://www.pericom.com
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