tl7700a series july 2000 supply voltage supervisors ? . power-on reset generator . automatic reset generation after voltage drop . wide supply voltage range ... 3v to 18v . precision voltage sensor . temperature-compensated voltage reference . true and complement reset outputs . externally adjustable pulse width n minidip description the tl7700a series are monolithic supply voltage supervisoric's specificallydesignedforuseas reset controllers in microcomputer and microprocessor systems. during power-up the device tests the sup- ply voltage and keeps the reset and reset out- puts active (high and low, respectively) as long as the supply voltage has not reached its nominal volt- age value. taking resin low has the same effect. to ensurethat the microcomputersystemhasreset, the tl7700a then initiates an internal time count that delays the return of the reset outputs to their in- active states. since the time delay for most micro- computers and microprocessors is in the order of several machine cycles, the device internaltime de- lay is determined by an external capacitor con- nected to the c t input (pin 3). t po = 1.3 x 10 4 xc t where : c t is in farads (f) and t po in seconds (s). in addition, when the supply voltage drops below the nominal value, the outputs will be active until the supply voltage returns to the nominal value. an ex- ternalcapacitor(typically0.1 m f) must be connected to the ref output (pin 1) to reduce the influence of fast transients in the supply voltage. the tl7700ai series is characterized for operation from 25 o cto85 o c ; the tl7700ac series is char- acterized from 0 o cto70 o c. d so8 ordering numbers temperature range minidip s08 0to70 o c tl77xxacp tl77xxacd -25 to 85 o c tl77xxaip tl77xxaid pin connection (top view) 1/7
* tl7702a r1 = 0 w , r2 = open ; tL7705A r1 = 7.8 k w , r2 = 10k w ; tl7709a r1 = 19.7 k w , r2 = 10k w ; tl7712a r1 = 32.7k w , r2 = 10k w ; tl7715a r1 = 43.4 k w , r2 = 10k w . block diagram absolute maximum ratings symbol parameter value unit v s supply voltage, v cc - (see note 1) 20 v v i input voltage range at resin -0.3 to 20 v v i input voltage at sense : tl7702a (see note 2) tL7705A -0.3 to 6 -0.3 to 10 v i oh high-level output current at reset -30 ma i ol low-level output current at reset 30 ma t amb operating free-air temperature range : tl77xxai tl77xxac -25 to 85 0to70 o c t stg storage temperature range -65 to 150 o c notes : 1. all voltage values are with respect to the network ground terminal 2. for the tl7700a, the voltage applied to the sense terminal must never exceed v s . thermal data symbol parameter value unit r th j-amb thermal resistance junction-ambient max. 120 o c/w recommended operating conditions symbol parameter min. max. unit v s supply voltage 3.6 18 v v ih high-level input voltage at resin 2 v v il low-level input voltage at resin 0.6 v v i voltage at sense input tl7702a tL7705A 0 0 see note 3 10 v i oh high-level output current at reset -16 ma i ol low-level output current at reset 16 ma t amb operating free-air temperature range tl77-ai tl77-ac -25 0 85 70 o c note : 3. for proper operation of the tl7702a, the voltage applied to the sense terminal should not exceed v s - 1v or 6v, which ever is less. tl7700a series 2/7
electrical characteristics t hese specifications unless otherwise specified, apply for : t amb = 25 to 85 o c (tlxxai), t amb = 0 to 70 o c (tl77xxac) symbol parameter test conditions (1) min. typ. max. unit v oh high-level output voltage at reset i oh = 16ma v s - 1.5 v v ol low-level output voltage at reset i ol = 16ma 0.4 v v ref reference voltage t amb =25 o c 2.48 2.53 2.58 v v t threshold voltage at sense input tl7702a tL7705A v s = 3.6v to 18v t amb =25 o c 2.48 4.5 2.53 4.55 2.58 4.6 v v t threshold voltage at sense inpu tl7702a tL7705A v s = 3.6v to 18v 2.45 4.45 2.53 4.55 2.58 4.6 v v t+ ,v t hysteresis (2) at sense input tl7702a tL7705A v s = 3.6v to 18v t amb =25 o c 10 15 mv i i input current at resin input v i = 2.4v to v s v i = 0.4v 20 -100 m a i i input current at sense input tl7702a v ref tl7705 figure 1 : reset controller for m p tl7700a series 4/7
dim. mm inch min. typ. max. min. typ. max. a 1.75 0.069 a1 0.1 0.25 0.004 0.010 a2 1.65 0.065 a3 0.65 0.85 0.026 0.033 b 0.35 0.48 0.014 0.019 b1 0.19 0.25 0.007 0.010 c 0.25 0.5 0.010 0.020 c1 45 (typ.) d (1) 4.8 5.0 0.189 0.197 e 5.8 6.2 0.228 0.244 e 1.27 0.050 e3 3.81 0.150 f (1) 3.8 4.0 0.15 0.157 l 0.4 1.27 0.016 0.050 m 0.6 0.024 s8 (max.) (1) d and f do not include mold flash or protrusions. mold flash or potrusions shall not exceed 0.15mm (.006inch). so8 outline and mechanical data tl7700a series 5/7
minidip dim. mm inch min. typ. max. min. typ. max. a 3.32 0.131 a1 0.51 0.020 b 1.15 1.65 0.045 0.065 b 0.356 0.55 0.014 0.022 b1 0.204 0.304 0.008 0.012 d 10.92 0.430 e 7.95 9.75 0.313 0.384 e 2.54 0.100 e3 7.62 0.300 e4 7.62 0.300 f 6.6 0.260 i 5.08 0.200 l 3.18 3.81 0.125 0.150 z 1.52 0.060 outline and mechanical data tl7700a series 6/7
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