ts 12001 page 1 ? 2012 touchstone semiconductor, inc. all rights reserved. features ? nanopower voltage detector in single 4 mm 2 package ? ultra low total supply current: 1a (max) ? supply voltage operation: 0.65v to 2.5v ? preset 0.78 v uvlo trip threshold ? internal 10mv hysteresis ? resettable latched comparator ? complimentary and open - drain comparator outputs ? separate comparator output su pply pin applications power - fail indicator low - battery detection battery - backup detection cpu, microprocessor , and logic reset controller battery - powered systems description the ts120 01 voltage detector combine s a 0.58 v reference and a comparator with resettable comparator latch in a single package. the TS12001 operate s from a single 0.65 v to 2.5v power supply and consume s less than 1 a total supply current. optimized for ultra - long life operation , the TS12001 expand s touchstones growing nanowatt ana log? high - performance analog integrated circuits portfolio. the voltage detector exhibits a pres et uvlo threshold voltage of 0.78 v (typ) or can be set to other threshold voltages with two external resistors. the comparator exhibits 10 mv of internal hyst eresis for clean, chatter - free output switching. the TS12001 also offers both push - pull and open - drain outputs. when compared against similar products, the ts120 0 1 offer s a factor - of - 2 lower pow er consumption and at least a 33 % reduction in pcb area. the ts 12 0 01 is fully specified over the - 40c to +85c temperature range and is available in a low - profile, 10 - pin 2x2mm tdfn package with an exposed back - side paddle. a 0.65v/1a nanopower vol tage detector with dual outputs typical application circuit t he touchstone semicondu c tor logo and nanowatt analog are registered trademark s of touchstone semiconductor, incorporated. a nanopower 1.8v core system voltage detector
ts120 01 page 2 TS12001ds r1p0 rtfds absolute maximum rat ings supply voltage (v in to v ss ) ............ ..................... ........... ....... +2.75 v supply voltage ( o v dd to v ss ) ............ ............................. ....... +2.75v input voltage set... .. ..v ss C 0.3v to v in + 0.3v et ..... .. . v ss - 0.3v to +5.5v output voltage ref out . .. . ... v ss C 0.3v to v in + 0.3v c out pp.. ...... . . . v ss - 0.3v to o v dd + 0.3v c o ut od .. .. . . v ss - 0.3v to +5.5v output current coutpp, c out od ... .. ............ ... ...............20 ma short - circuit duration (refout, c out pp, coutod ) ... ... . c ontinuous continuous power dissipation (t a = +70c) 10 - pin tdfn (derate at 13.48 mw/c above +70c) ......... 1078 mw operating temperature range ................................ - 40c to +85c unction temperature..+150 c storage temperature range ................................ . - 65c to +150c lead temperature (s oldering, 10s) ................................ ..... +300c electrical and thermal s tresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. these are stress ratings only and functional operation of the device at these or any other condition beyond those indicated in the operational sections of the specifications is not implied. exposure to any absolute maximum rating conditions for extended periods may affect device reliability and lifetime . package/ordering information order nu mber part marking carrier quantity ts 12001 itd 10 22t p aa n tape & reel ----- ts 12 0 01 itd 10 22t tape & reel 3000 lead - free program: touchstone semico nductor supplies only lead - free packaging. consult touchstone semiconductor for products specified with wid er operating temperature ranges.
TS12001 TS12001ds r1p0 page 3 rtfds electrical character istics v in = ov dd = 0. 8 v; v ss = 0v ; v set = v ss ; v c out pp = hiz ; v co utod = hiz ; t a = - 40c to +85c, unless otherwise noted. typical values are at t a = +25c. see n ote 1. parameter symbol conditions min typ max units supply voltage v in 0. 65 2.5 v supply current i in refout = open t a = +25c 0.8 a - 40c a dd 0.65 2.5 v output driver supply current i odd 0.1 a preset uvlo trip point v in falling until coutpp switches low 725 761 797 mv v in rising until coutpp switches high 743 78 1 818 set trip point v set falling until coutpp switches low t a = +25c 54 0 567 595 - 40 t a 85 set rising until coutpp switches high t a = +25c 56 0 587 615 - 40 t a 85 set rising 13 s v set f alling 10 preset uvlo trip hysteresis 10 mv set enable threshold see note 2 90 mv set input leakage v set = v ss ; v set = v in 2 0 na et il comparator latched output enabled 0.78 v in in et ih comparator latched output disabled 0. 7 8v in in - 0.1 v 1.1v < v in et v et ss ; v et ref t a = +25c 555 5 77 600 mv - 40 t a 85 out = 100na 0.5 % output high voltage v oh coutpp; i out = - 100a in C ol coutpp; i out = 100a ss + 0.1 v output low voltag e v ol coutod; i out = 100a ss + 0.11 v output short - circuit current, i sc sourcing; v coutpp = v ss 0.1 ma sinking; v coutpp = v in 0.5 ma sinking; v coutod = v in 1.4 ma open drain leakage coutod ; v coutod = 5v 20 na note 1: all devices are 100% production tested at t a = +25c and are guaranteed by characterization for t a = t min to t max , as specified. note 2: a set voltage above this threshold voltage enables the set pin voltage to control the comparator output.
TS12001 page 4 TS12001ds r1p0 rtfds pin functions pin name function 1 vin positive supply voltage. connect a 0.1f bypass capacitor from this pin to analog vss/ gnd. 2 set external uvlo trip threshold set pin. when this pin is set to vss , the internal preset 0.78 v uvlo trip threshold controls the compar ator output. when the applied volta ge to this pin is higher than 90 mv , the set pin sets the trip threshold and controls the comparator output. if the set pin is not used, connect the pin to to vss. 3 nc no connection 4 vss negative supply voltage. 5 et latch enable pin. when et is set high , the output s of the comparator will toggle normally based on the inputs to the comparator. when et is set low and coutpp is high, coutpp will remain high despite any changes to the inpu t of the compara tor. coutpp will once again respond to changes to the input when et is toggled high. if coutpp is initially low and the et is then low, coutpp will stay low. if a low - to - high transition occurs on coutpp , coutpp will switch to high and stay high a nd not respond to any changes at the input. the et pin must always be set to a known state. for unlatched comparator operation, set et to high. the open - drain output (coutod) is the inverted version of the coutpp output. 6 refout 0.58 v reference output 7 nc n o c onnection 8 coutod comparator open - d rain o utput 9 coutpp comparator push - pull o utput 10 ovdd output driver positive supply voltage. connect a 0.1f bypass capacitor from this pin to analog vss/ gnd. ep ---- exposed paddle is electrica lly connected to vss/ gnd.
ts 12001 TS12001ds r1p0 page 5 rtfds block diagram theory of operation the TS12001 combine s a 0. 58 v 4.5% reference and an analog comparator with a resettable comparator latch in a single package. the ts 1 2001 operate s from a single 0.65 v to 2.5v power supply and consume s less than 1 a total supply current. the TS12001 comparator has a push - pull a nd open - drain output driver. the push - pull output driver is powered from a separate supply voltage, ov dd . the open - drain output stage allows for easy output voltage l evel translation as may be required when driving systems powered with a different power supply rail. t he analog comparator exhibits 10 mv of internal hysteresis for clean, chatter - free output switching. the internal reference was designed to sink or source up to 0.1a load currents. the TS12001 has a pres et uvlo threshold voltage of 0.78 v (typ) or can be set to other threshold voltages with two external resistors where the divided voltage is applied to the set pin. when the set pin voltage is grounded or i t is less than approximately 90 mv, the internal preset uvlo threshold circuit will control the comparator output s . if the set pin is above approximately 90 mv, the external voltage divider circuit will control the comparator outputs . t he 0.58 v reference vol tage is tied to the inverting input of the comparator and the output of a switch is connected to the non - inverting input of the comparator. the output of the switch is either the set voltage or the internal uvlo threshold voltage, depending on whether the set pin voltage is above or below approximately 90 mv. if the switch output is above 0.58 v, the pu sh - pull output ( coutpp ) will be high and the op en - drain output ( coutod) will be low and vice versa. for proper operation, the supply voltage v in must be applie d before th e output driver supply voltage ( ov dd ) is applied . the TS12001 has a latch enable pin ( et ) that
TS12001 page 6 TS12001ds r1p0 rtfds allows the output of the comparator to latch to a high state under certain conditions. if et is set high , the c out pp out put will switch ba sed on the input to the comparator. when et is set low and c out pp is high, c out pp will remain high until et goes low. when c out pp is initially low instead, c out pp will latch high until a low - to - hi gh transition occurs on the c out pp output. in esse nce, the et pin offers a low - to - high detection. however, et must not be left open. the open - drain output, coutod, is the inverter version of the coutpp output. connect et to v in for normal operation or to v ss for et enable. if the set pin is not used, it cannot be left unconnected and should be tied to v ss . comparator the TS12001 has an intern al comparator that can eliminate supply gl itches that commonly occur when output transitions occur. in addition, the input exhibits 10mv of i nternal hysteresis in order to insure clean output switching behavior. the outputs can swin g to within 100mv of the supply rail s . the cou t pp output can source and sink 0.1 ma and 0 .5ma of current. t he coutd outputs can sink 1.4 ma of current with v coutod = 0 . 7 8v internal reference the TS12001 s on - board 0.58 v 4.5% reference voltage can source and sink 0.1 a and 0.1a of current and can drive a capacitive load le ss than 50pf and greater than 50 nf with a maximum capacitive load of 250n f. the higher the capa citive load, the lower the noise on the reference voltage and the longer the time needed for the reference voltage to respond and become availa ble on the refout pin. with a 250n f capacitive load, the r esponse time is approximately 20ms. while also available as a separate pin as refout , the refere nce is tied internally to the inverting input of the comparator . applications information externa l voltage detector design depending on the battery voltage used an d the voltage one wishes to detect, the TS12001 can be designed a ccordingly. as shown in figure 1 , r1 and r2 can be selected based on the desired voltage to detect. table 1. provides r1 and r2 resistor combinations for detecting various v in voltages. v i n threshold voltage(v) r1 (m ) r2 (m ) 0.9 2.2 4.02 1. 07 3.32 4.02 1. 28 4.75 4.02 1. 52 6.49 4.02 1.85 8.66 4.02 table 1. resistor combinations for several v in threshold voltages the design equation for this circuit is shown below. the set pin voltage (v set ) that will cause a high - to - low transition on the output is approximately 580 mv. to design the circuit, r1 or r2 can be selected along with the desired battery voltage to detect. then, the second resistor value can be evaluated using the voltage divi der equation below. r 1 = v n x r v set x r v set a nanopower 1.8v core system voltage detector when power supply rails sag in any system, it is important to alert the cpu. a cpu can be used to detect when i/o or core system voltages sag below a prescribed threshold as shown figure 2 . in this circuit, a 1.8v core system voltage detector is designed around the TS12001 providing a low battery detect signal . r1 and r2 were sele cted to set a set voltage at 582 mv so that when vcor e drops below 1.77v, the TS12001 output transitions to low. it is recommended to use 1% resistors for optimal accuracy. the cir cuit consumes approximately 0.75 a of current when vcore = 1.8v. pc board layout and power - supply bypassing while power - supply bypass capacitors a re not typically required, it is good engineering practice to use 0.1uf bypass capacitors close to the devices power supply pins. when the power supply impedance is high, the power supply leads are long, or there is excessive noise on the power supply tra ces. to reduce stray capacitance, it is also good
ts 12001 TS12001ds r1p0 page 7 rtfds engineering practice to make signal trace lengths as short as possible. also recommended are a ground plane and surface mount resistors and capacitors. input noise radiated noise is common in low power ci rcuits that require high impedance circuits. to minimize this effect, all traces between any of the inputs and passive component networks should be made as short as possible. figure 2 . a nanopower 1.8v core system voltage detector circuit figure 1 . external voltage detector design circuit
TS12001 touchstone semiconductor, inc. page 8 630 alder drive, milpitas , ca 95035 TS12001ds r1p0 +1 (408) 215 - 1220 ? www.touchstonesemi.com rtfds p ack age outline drawing information furnished by touchstone s emiconductor is believed to be accurate and reliable. however, touchstone semiconductor does not assume any responsibility for its use nor for any infringements of patents or other rights of third parties that may result f rom its use , and all information p rovided by touchstone semiconductor and its suppliers is provided on an as is basis, without warranty of any kind . touchstone semiconductor reserves the right to change product specifications and product descriptions at any time without any advance notice. no license is granted by implication or otherwise under any patent or patent rights of touchstone semiconductor. touchstone semiconductor assumes no liability for applications assistance or customer product design. customers are responsible for thei r prod ucts and applications using touchstone semiconductor components. to minimize the risk associated with customer products and applicatio ns, custo mers should provide adequate design and operating safeguards. trademarks and registered trademarks are the property of their respective owners. 10 - pin tdfn22 package outline drawing (n .b., drawings are not to scale) 0 . 2 0 0 0 . 0 5 0 b o t t o m v i e w 2 . 0 0 0 0 . 0 5 0 2 . 0 0 0 0 . 0 5 0 t o p v i e w 1 0 l s t s l p ( 2 x 2 m m ) p i n 1 d o t b y m a r k i n g p i n # 1 i d e n t i f i c a t i o n 0 . 1 5 2 r e f a 0 . 0 0 0 - 0 . 0 5 0 n o t e ! a l l d i m e n s i o n s i n m m . t h i s p a r t i s c o m p l i a n t w i t h j e d e c m o - 2 2 9 s p e c a m a x . n o m . m i n . 0 . 6 0 0 0 . 5 5 0 0 . 5 0 0 s i d e v i e w 0 . 9 0 0 0 . 0 5 0 e x p . d a p 1 . 4 0 0 0 . 0 5 0 e x p . d a p 0 . 3 0 0 0 . 0 5 0 0 . 4 0 0 b s c
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