1 industrial temperature range idt74fst163245 16-bit bus switch may 2002 industrial temperature range the idt logo is a registered trademark of integrated device technology, inc. ? 2002 integrated device technology, inc. dsc-5513/2 features: ? bus switches provide zero delay paths ? low switch on-resistance ? ttl-compatible input and output levels ? esd > 2000v per mil-std-883, method 3015; > 200v using machine model (c = 200pf, r = 0) ? hot insertion capability ? very low power dissipation ? available in ssop and tssop packages functional block diagram idt74fst163245 16-bit bus switch description: the fst163245 belongs to idt's family of bus switches. bus switch devices perform the function of connecting or isolating two ports without providing any inherent current sink or source capability. thus they generate little or no noise of their own while providing a low resistance path for an external driver. these devices connect input and output ports through an n-channel fet. when the gate-to-source junction of this fet is adequately forward-biased the device conducts and the resistance be- tween input and output ports is small. without adequate bias on the gate- to-source junction of the fet, the fet is turned off, therefore with no v cc applied, the device has hot insertion capability. the low on-resistance and simplicity of the connection between input and output ports reduces the delay in this path to close to zero. the fst163245 is pin compatible with and functionally similar to fct16245. 1a 1 1b 1 1a 8 1b 8 2b 1 2b 8 2a 1 2a 8 1oe 2oe
2 industrial temperature range idt74fst163245 16-bit bus switch ssop/ tssop top view pin configuration symbol description max unit v term (2) terminal voltage with respect to gnd ?0.5 to +7 v t stg storage temperature ?65 to +150 c i out maximum continuous channel current 128 ma absolute maximum ratings (1) notes: 1. stresses greater than those listed under absolute 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 specification is not implied. exposure to absolute maximum rating conditions for extended periods may affect reliability. 2. vcc, control, and switch terminals. symbol parameter conditions (2) typ. unit c in control input capacitance 6 pf c i/o switch input/output capacitance switch off 12 pf capacitance (1) notes: 1. capacitance is characterized but not tested. 2. t a = 25c, f = 1mhz, v in = 0v, v out = 0v. note: 1. h = high voltage level l = low voltage level function table (1) inputs x oe outputs l connect a to b h disconnect a from b 5 6 7 8 9 10 1 2 3 4 46 45 44 43 42 41 40 39 38 37 gnd 1 b 1 1 b 2 gnd 1 b 3 1 b 4 v cc 1 b 5 1 b 6 1 a 2 gnd 1 a 3 1 a 4 v cc 1 a 5 1 a 6 gnd 1 oe 2 oe 1 a 1 nc 1 b 7 11 12 47 48 1 b 8 1 a 7 1 a 8 17 18 19 20 21 22 13 14 15 16 34 33 32 31 30 29 28 27 26 25 2 b 7 2 b 2 gnd 2 b 3 2 b 4 v cc 2 b 5 2 b 6 gnd gnd 2 a 3 2 a 4 v cc 2 a 5 2 a 6 gnd 2 a 7 2 a 1 2 a 2 2 b 1 2 b 8 23 24 35 36 nc 2 a 8 pin names i/o description 1a 1-8 , 2a 1-8 i/o bus a 1b 1-8 , 2b 1-8 i/o bus b 1 oe , 2 oe i bus switch enable (active low) pin description
3 industrial temperature range idt74fst163245 16-bit bus switch symbol parameter test conditions (1) min. typ. (2) max. unit v ih control input high voltage guaranteed logic high for control inputs 2 ? ? v v il control input low voltage guaranteed logic low for control inputs ? ? 0.8 v i ih control input high current v cc = max. v i = v cc ?? 1a i il control input low current v i = gnd ? ? 1 i ozh current during v cc = max., v o = 0 to 5v ? ? 1a i ozl bus switch disconnect ? ? 1 v ik clamp diode voltage v cc = min., i in = ?18ma ? ?0.7 ?1.2 v i off switch power off leakage v cc = 0v, v in or v o 5.5v ? ? 1a i cc quiescent power supply current v cc = max., v in = gnd or v cc ? 0.1 3 a dc electrical characteristics over operating range following conditions apply unless otherwise specified: industrial: t a = ?40c to +85c, v cc = 5.0v 10% bus switch impedance over operating range following conditions apply unless otherwise specified: industrial: t a = -40c to +85c, v cc = 5.0v 10% symbol parameter test conditions min. typ. (1) max. unit r on switch on resistance (2) vcc = min., v in = 0v, i on = 30ma ? 5 7 ? vcc = min., v in = 2.4v, i on = 15ma ? 10 15 i os short circuit current (3) a(b) = 0v, b(a) = vcc 100 ? ? ma notes: 1. typical values are at vcc = 5.0v, +25c ambient. 2. the voltage drop between the indicated ports divided by the current through the switch. 3. not more than one output should be shorted at one time. duration of the test should not exceed one second.
4 industrial temperature range idt74fst163245 16-bit bus switch symbol parameter test conditions (1) min. typ. (2) max. unit ? i cc quiescent power supply current v cc = max. ? 0.5 1.5 ma ttl inputs high v in = 3.4v (3) i ccd dynamic power supply v cc = max., outputs open v in = v cc ? 240 320 a/ current (4,5) one enable pin toggling v in = gnd mhz/ 50% duty cycle enable i c total power supply current (6) v cc = max., outputs open v in = v cc ? 4.8 6.4 ma two enable pins toggling v in = gnd f i = 10mhz v in = v cc ? 5.3 7.9 50% duty cycle v in = 3.4v power supply characteristics notes: 1. for conditions shown as max. or min., use appropriate value specified under electrical characteristics for the applicable dev ice type. t a = ?40c to +85c 2. typical values are at v cc = 5.0v, +25c ambient. 3. per ttl driven input (v in = 3.4v). all other inputs at v cc or gnd. switch inputs do not contribute to ? i cc. 4. this parameter represents the current required to switch the internal capacitance of the control inputs at the specified freq uency. switch inputs generate no significant power supply currents as they transition. this parameter is not directly testable, but i s derived for use in total power supply calculations. 5. c pd = i ccd /v cc c pd = power dissipation capacitance 6. i c = i quiescent + i inputs + i dynamic i c = i cc + ? i cc d h n t + i ccd (f i n) i cc = quiescent current ? i cc = power supply current for a ttl high input (v in = 3.4v) d h = duty cycle for ttl inputs high n t = number of ttl inputs at d h i ccd = dynamic current caused by an input transition pair (hlh or lhl) f i = control input frequency n = number of control inputs toggling at f i switching characteristics over operating range following conditions apply unless otherwise specified: industrial: t a = -40c to +85c, v cc = 5.0v 10% symbol description min. (1) typ. max. unit t plh data propagation delay ? ? 0.25 ns t phl a to b, b to a (2) t pzh switch connect delay 1.5 ? 6.5 ns t pzl x oe to a or b t phz switch disconnect delay 1.5 ? 5.5 ns t plz x oe to a or b |q ci | charge injection during switch disconnect ? 1.5 ? pc x oe to a or b (3) notes: 1. see test circuits and waveforms. 2. the bus switch contributes no propagation delay other than the rc delay of the load interacting with the rc of the switch. 3. |q ci | is the charge injection for a single switch disconnect and applies to either single switches or multiplexers. charge injection is reduced because the injection from the disconnect of the first path is compensated by the connect of the second path.
5 industrial temperature range idt74fst163245 16-bit bus switch d.u.t. v cc 1 mhz signal generator c l = 50 p f v out switch out enable/select switch in switch in (mux) (1) pulse generator r t d.u.t. v cc v in c l v out 50pf 500 ? 500 ? 7.0v 3v 1.5v 0v 3v 1.5v 0v 3v 1.5v 0v 3v 1.5v 0v data input timing input asynchronous control synchronous control t su t h t rem t su t h same phase input transition 3v 1.5v 0v 1.5v v oh t plh output opposite phase input transition 3v 1.5v 0v t plh t phl t phl v ol control input 3v 1.5v 0v 3.5v output o switch t plz t pzl 3.5v enable disable (2) (3) test circuits and waveforms propagation delay test circuits for all outputs enable and disable times set-up, hold, and release times pulse width notes: 1. diagram shown for input control enable-low and input control disable-high. 2. pulse generator for all pulses: rate 1.0mhz; t f 2.5ns; t r 2.5ns. test switch open drain disable low closed enable low all other tests open switch position definitions: c l = load capacitance: includes jig and probe capacitance. r t = termination resistance: should be equal to z out of the pulse generator. charge injection notes: 1. select is used with multiplexers for measuring iq dci i during multiplexer select. during all other tests enable is used. 2. used with multiplexers to measure iq dci i only. 3. charge injection = ? v out c l , with enable toggling for iq ci i or select toggling for iq dci i. ? v out is the change in v out and is measured with a 10m ? probe.
6 industrial temperature range idt74fst163245 16-bit bus switch ordering information corporate headquarters for sales: for tech support: 2975 stender way 800-345-7015 or 408-727-6116 logichelp@idt.com santa clara, ca 95054 fax: 408-492-8674 (408) 654-6459 www.idt.com 5/28/2002 removed tvsop package data sheet document history idt xx temp. range xxx device type x package 74 ?40c to +85c pv pa pag 245 shrink small outline package thin shrink small outline package tssop - green 16-bit flow through bus switch fst family xxx 163 double-density bus switch
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