lm66 dual output internally preset thermostat general description the lm66 is a precision low power thermostat. two stable temperature trip points (v t1 and v t2 ) are generated by divid- ing down the lm66 1.250v bandgap voltage reference using a resistors divider network. the lm66 has two digital out- puts. out1 goes low when the temperature exceeds t1 and goes high when the the temperature goes below (t1t hyst ). similarly, out2 goes low when the tempera- ture exceeds t2 and goes high when the temperature goes below (t2t hyst ). t hyst is an internally set 5c typical hys- teresis. the lm66 is currently available in an 8-lead small outline package. applications n microprocessor thermal management n appliances n portable battery powered 3.0v or 5v systems n fan control n industrial process control n hvac systems n remote temperature sensing n electronic system protection features n digital outputs support ttl logic levels n internal temperature sensor n 2 internal comparators with hysteresis n internal voltage reference n currently available in 8-pin so plastic package key specifications j power supply voltage 2.7v to 10v j power supply current 250 a (max) j v ref 1.250v 1.4% (max) j hysteresis temperature 5c j internal temperature sensor output voltage (+6.20 mv/c x t) +400 mv n temperature trip point accuracy 3c (max) n t1 set point +73c n t2 set point +82c simplified block diagram and connection diagram ordering information table 1. order number lm66cim- rlskb lm66cimx- rlskb ns tackage number m08a m08a transport media bulk rail 2500 units tape & reel typical application ds100854-1 ds100854-2 ds100854-3 april 2000 lm66 dual output internally preset thermostat ? 2000 national semiconductor corporation ds100854 www.national.com
absolute maximum ratings (note 1) input voltage 12v input current at any pin (note 2) 5 ma package input current (note 2) 20 ma package dissipation at t a = 25c (note 3) 900 mw esd susceptibility (note 4) human body model 1000v machine model 200v soldering information so package (note 5) : vapor phase (60 seconds) 215c infrared (15 seconds) 220c storage temperature ?65c to + 150c operating ratings (note 1) operating temperature range t min t a t max lm66cim ?40c t a +125c positive supply voltage (v + ) +2.7v to +10v maximum v out1 and v out2 +10v lm66 electrical characteristics the following specifications apply for v + = 2.7 v dc , and v ref load current = 0 a unless otherwise specified. boldface lim- its apply for t a =t j =t min to t max ; all other limits t a =t j = 25c unless otherwise specified. typical lm66cim units symbol parameter conditions (note 6) limits (limits) (note 7) temperature sensor trip point accuracy (includes v ref , comparator offset, and +25c t a +85c 3 c (max) temperature sensitivity errors) trip point hysteresis t a = +73c 6 4.5 c (min) 7.5 c (max) t a = +82c 6 4.5 c (min) 7.5 c (max) internal temperature sensitivity +6.20 mv/c temperature sensitivity error +25c t a +85c 3 c (max) ?25c t a +125c 4 c (max) ?40c t a ?25c 5 c (max) output impedance ?1 a i l +40 a 1500 w (max) line regulation +3.0v v + +10v, +25c t a +85c 0.36 mv/v (max) +3.0v v + +10v, ?40c t a < 25c 0.61 mv/v (max) +2.7v v + +3.3v 2.3 mv (max) v ref output v ref v ref nominal 1.250v v v ref error 1.4 % (max) 17.5 mv (max) d v ref / d v + line regulation +3.0v v + +10v 0.13 0.21 mv/v (max) +2.7v v + +3.3v 0.15 1.5 mv (max) lm66 www.national.com 2
lm66 electrical characteristics the following specifications apply for v + = 2.7 v dc , and v ref load current = 50 a unless otherwise specified. boldface lim- its apply for t a =t j =t min to t max ; all other limits t a =t j = 25c unless otherwise specified. symbol parameter conditions typical limits units (note 6) (note 7) (limits) v + power supply i s supply current v + = +10v 250 a (max) v + = +2.7v 250 a (max) digital output(s) i out(a1o) logical a1o output leakage current v + = +5.0v 1 a (max) v out(a0o) logical a0o output voltage i out = +50 a 0.4 v (max) note 1: absolute maximum ratings indicate limits beyond which damage to the device may occur. operating ratings indicate conditions for which the device is f unc- tional, but do not guarantee specific performance limits. for guaranteed specifications and test conditions, see the electrical characteristics. the guaranteed speci- fications apply only for the test conditions listed. some performance characteristics may degrade when the device is not operated under the listed te st conditions. note 2: when the input voltage (v i ) at any pin exceeds the power supply (v i < gnd or v i > v + ), the current at that pin should be limited to 5 ma. the 20 ma maxi- mum package input current rating limits the number of pins that can safely exceed the power supplies with an input current of 5 ma to four. note 3: the maximum power dissipation must be derated at elevated temperatures and is dictated by t jmax (maximum junction temperature), q ja (junction to am- bient thermal resistance) and t a (ambient temperature). the maximum allowable power dissipation at any temperature is p d =(t jmax t a )/ q ja or the number given in the absolute maximum ratings, whichever is lower. for this device, t jmax = 125c. for this device the typical thermal resistance ( q ja ) of the different package types when board mounted follow: package type q ja m08a 110c/w note 4: the human body model is a 100 pf capacitor discharge through a 1.5 k w resistor into each pin. the machine model is a 200 pf capacitor discharged directly into each pin. note 5: see an450 asurface mounting methods and their effects on product reliabilityo or the section titled asurface mounto found in any post 1986 national se mi- conductor linear data book for other methods of soldering surface mount devices. note 6: typicals are at t j =t a = 25c and represent most likely parametric norm. note 7: limits are guaranteed to national's aoql (average outgoing quality level). lm66 www.national.com 3
part number template the series of digits labled vw xy z in the part number lm66cim-vw xy z, describe the set points and the function of out1 and out2 as follows: the place holder s v w describe the set point of t1 as shown in the following table. the place holders xy describe the set point of t2 as shown in the following table. z=0 (other assignments are reserved.) for example the part number lm66cim-rlskb has: t1 = 73c, t2 = 82c, out1 and out2 set as active-low open-collector outputs with out1 mapped to pin 7 and out2 mapped to pin 6. v, w, x and y temperature (c) b?5 c?4 d?3 f?2 g?1 h?0 j1 k2 l3 n4 v, w, x and y temperature (c) p5 q6 r7 s8 t9 v10 x11 y12 z13 the value of z describes the assignment/function of out1 and out2 as shown in the following table: active low//high open collector/ totem pole mapping value of z function of out1 and out2 0 0 0 b active-low, open-collector, out1 mapped to pin 7, out2 mapped to pin 6 0 0 1 c active-low, open-collector, out1 mapped to pin 6, out2 mapped to pin 7 0 1 0 d active-low, totem pole, out1 mapped to pin 7, out2 mapped to pin 6 0 1 1 f active-low, totem pole, out1 mapped to pin 6, out2 mapped to pin 7 1 0 0 g active-high, open-collector, out1 mapped to pin 7, out2 mapped to pin 6 1 0 1 h active-high, open-collector, out1 mapped to pin 6, out2 mapped to pin 7 1 1 0 j active-high, totem pole, out1 mapped to pin 7, out2 mapped to pin 6 1 1 1 k active-high, totem pole, out1 mapped to pin 6, out2 mapped to pin 7 lm66 www.national.com 4
physical dimensions inches (millimeters) unless otherwise noted life support policy national's products are not authorized for use as critical components in life support devices or systems without the express written approval of the president and general counsel of national semiconductor corporation. as used herein: 1. life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. 2. a critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. national semiconductor corporation americas tel: 1-800-272-9959 fax: 1-800-737-7018 email: support@nsc.com national semiconductor europe fax: +49 (0) 180-530 85 86 email: europe.support@nsc.com deutsch tel: +49 (0) 69 9508 6208 english tel: +44 (0) 870 24 0 2171 fran?ais tel: +33 (0) 1 41 91 8790 national semiconductor asia pacific customer response group tel: 65-2544466 fax: 65-2504466 email: ap.support@nsc.com national semiconductor japan ltd. tel: 81-3-5639-7560 fax: 81-3-5639-7507 www.national.com 8-lead (0.150" wide) molded small outline package, jedec order number lm66cim or lm66cimx ns package number m08a lm66 dual output internally preset thermostat national does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and national reserves the righ t at any time without notice to change said circuitry and specifications.
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