1 idtqs3245 high-speed cmos quickswitch 8-bit bus switch industrial temperature range february 2011 2011 integrated device technology, inc. dsc-5753/5 c idtqs3245 industrial temperature range quickswitch ? products high-speed cmos quickswitch 8-bit bus switch functional block diagram the idt logo is a registered trademark of integrated device technology, inc. features: ? enhanced n channel fet with no inherent diode to vcc ?5 bidirectional switches connect inputs to outputs ? pin compatible with the 74f245, 74fct245, and 74fct245t ? low power cmos proprietary technology ? zero propagation delay, zero ground bounce ? undershoot clamp diodes on all switch and control inputs ? ttl-compatible control inputs ? available in soic and qsop packages applications: ? hot-swapping, hot-docking ? voltage translation (5v to 3.3v) ? power conservation ? capacitance reduction and isolation ? logic replacement (data processing) ? clock gating ? bus switching and isolation description: the qs3245 provides a set of eight high-speed cmos ttl-compatible bus switches in a pinout compatible with 74fct245, 74f245, 74als/as/ ls245 8-bit transceivers. the low on resistance of the qs3245 allows inputs to be connected to outputs without adding propagation delay and without generating additional ground bounce noise. the output enable ( oe ) signal turns the switches on similar to the oe signal of the 74?245. quickswitch devices provide an order of magnitude faster speed than conventional logic devices. the qs3245 is characterized for operation at -40c to +85c. b 0 oe a 0 b 1 a 1 b 2 a 2 b 3 a 3 b 4 a 4 b 5 a 5 b 6 a 6 b 7 a 7
2 industrial temperature range idtqs3245 high-speed cmos quickswitch 8-bit bus switch pin configuration soic/ qsop top view note: 1. h = high voltage level l = low voltage level function table (1) oe outputs h disconnected l ax = bx pin description pin names description oe output enable a x data i/os b x data i/os symbol description max unit v term (2) supply voltage to ground ?0.5 to +7 v v term (3) dc switch voltage vs ?0.5 to +7 v v term (3) dc input voltage v in ?0.5 to +7 v v ac ac input voltage (pulse width 20ns) ?3 v i out dc output current 120 ma p max maximum power dissipation (t a = 85c) 0.5 w t stg storage temperature ?65 to +150 c absolute maximum ratings (1) note: 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 terminals. 3. all terminals except vcc. 1 2 3 4 5 6 7 8 9 10 20 19 18 17 16 15 14 13 12 11 nc a 0 gnd v cc oe a 1 a 2 a 3 a 4 a 5 a 6 a 7 b 0 b 1 b 2 b 3 b 4 b 5 b 6 b 7 capacitance (t a = +25c, f = 1.0mh z , v in = 0v, v out = 0v) note: 1. this parameter is measured at characterization but not tested. pins typ. max. (1) unit control pins 3 5 pf quickswitch channels (switch off) 5 7 pf
3 idtqs3245 high-speed cmos quickswitch 8-bit bus switch industrial temperature range r on (ohms) v in (volts) typical on resistance vs v in at v cc = 5v symbol par ameter test conditions min. typ. (1) max. unit v ih input high level guaranteed logic high for control pins 2 ? ? v v il input low level guaranteed logic low for control pins ? ? 0.8 v i in input leakagecurrent (control inputs) 0v v in v cc ?? 1 a i oz off-state output current (hi-z) 0v v out v cc , switches off ? 0.001 1 a r on switch on resistance v cc = min., v in = 0v, i on = 30ma ? 5 7 v cc = min., v in = 2.4v, i on =15ma ? 10 15 v p pass voltage (2) v in = v cc = 5v, i out = -5 a 3.7 4 4.2 v dc electrical characteristics over operating range following conditions apply unless otherwise specified: industrial: t a = ?40c to +85c, v cc = 5.0v 5% notes: 1. typical values are at v cc = 5.0v, t a = 25c. 2. pass voltage is guaranteed but not production tested. 16 14 12 10 8 6 4 2 0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5
4 industrial temperature range idtqs3245 high-speed cmos quickswitch 8-bit bus switch power supply characteristics symbol parameter test conditions (1) max. unit i ccq quiescent power supply current v cc = max., v in = gnd or vcc, f = 0 3 a i cc power supply current per control input high (2) v cc = max., v in = 3.4v, f = 0 1.5 ma i ccd dynamic power supply current per mhz (3) v cc = max., a and b pins open 0.25 ma/mhz control inputs toggling at 50% duty cycle notes: 1. for conditions shown as min. or max., use the appropriate values specified under dc electrical characteristics. 2. per tll driven input (v in = 3.4v, control inputs only). a and b pins do not contribute to icc. 3. this current applies to the control inputs only and represents the current required to switch internal capacitance at the spe cified frequency. the a and b inputs generate no significant ac or dc currents as they transition. this parameter is guaranteed but not production tested. switching characteristics over operating range t a = -40c to +85c, v cc = 5.0v 5%; c load = 50pf, r load = 500 unless otherwise noted. symbol parameter min. (1) typ. max. unit t plh data propagation delay (2,3) ? ? 0.25 ns t phl an to/from bn t pzl switch turn-on delay 0.5 ? 5.6 ns t pzh oe to ax/bx t plz switch turn-off delay (2) 0.5 ? 4.5 ns t phz oe to ax/bx notes: 1. minimums are guaranteed but not production tested. 2. this parameter is guaranteed but not production tested. 3. the bus switch contributes no propagation delay other than the rc delay of the on resistance of the switch and the load capacit ance. the time constant for the switch alone is of the order of 0.25ns for c l = 50pf. since this time constant is much smaller than the rise and fall times of typical driving signals, it adds very littl e propagation delay to the system. propagation delay of the bus switch, when used in a system, is determined by the driving circuit on the driving si de of the switch and its interaction with the load on the driven side.
5 idtqs3245 high-speed cmos quickswitch 8-bit bus switch industrial temperature range ordering information qs xxxxx xx package device type blank industrial (-40c to +85c) small outline ic - green quarter size outline package - green sog qg 3245 high speed cmos quickswitch 8-bit bus switch x process x blank 8 tube or tray tape and reel corporate headquarters for sales: for tech support: 6024 silver creek valley road 800-345-7015 or 408-284-8200 logichelp@idt.com san jose, ca 95138 fax: 408-284-2775 www.idt.com datasheet document history 02/14/2011 pg. 5 updated the ordering information by removing the "idt" notation, non rohs part and by adding tape and reel information.
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