s s p p 8 8 0 0 9 9 / / s s p p 8 8 1 1 0 0 3 3 p p i i n n m m i i c c r r o o p p r r o o c c e e s s s s o o r r s s u u p p e e r r v v i i s s o o r r c c i i r r c c u u i i t t february 2011 rev. 2.0.0 exar corporation www.exar.com 48720 kato road, fremont ca 94538, usa tel. +1 510 668-7000 ? fax. +1 510 668-7001 general description the sp809/sp810 are low power microprocessor ( p) supervisory circuits used to monitor power supplies in p and digital systems. they provide applications with benefits of circuit reliability and low cost by eliminating external components. if the vcc supply voltage falls below preset threshold then a reset signal is asserted for at least 140ms after v cc has risen above the reset threshold. both the sp809 and sp810 were designed with a reset comparator to help identify invalid signals, which last le ss than 140ms. the only difference between them is that they have an active-low reset output and active-high reset output, respectively. low supply current (1 a) makes sp809/sp810 ideal for portable equipment. the devices are available in 3 pin sot-23 package. part number output type sp809n open drain active low sp809 push-pull low sp810 push-pull active high applications ? portable electronic devices ? electrical power meters ? digital still cameras ? p power monitoring features ? ultra low supply current 1a (typ) ? guaranteed reset valid to v cc = 0.9v ? 140ms power-on reset pulse width ? internally fixed threshold 2.3v, 2.6v, 2.9v, 3.1v, 4.4v, 4.6v ? 1.5% voltage threshold tolerance ? 3 pin sot-23 package typical application diagram fig. 1: sp809 / sp810 application diagram
s s p p 8 8 0 0 9 9 / / s s p p 8 8 1 1 0 0 3 3 p p i i n n m m i i c c r r o o p p r r o o c c e e s s s s o o r r s s u u p p e e r r v v i i s s o o r r c c i i r r c c u u i i t t ? 2011 exar corporation 2/8 rev. 2.0.0 absolute maximum ratings these are stress ratings only and functional operation of the device at these ratings or any other above those indicated in the operation sections of the specifications below is not implied. exposure to absolute maximum rating conditions for extended periods of time may affect reliability. v cc .......................................................... -0.3v to 6.5v reset, reset .................................... -0.3v to v cc +0.3v output current (reset, reset ) ............................. 20ma power dissipation (t a =70c) .............................. 320mw junction temp erature .......................................... 125c storage temperatur e .............................. - 65c to 150c operating ratings input voltage range v cc ................................ 0.9v to 6v junction temperature range ..................... -40c to 85c electrical specifications specifications with standard type are for an operating temperature of t a = 25c only; limits applying over the full operating temperature range are denoted by a ???. minimum an d maximum limits are guarant eed through test, design, or statistical correlation. typical values repres ent the most likely parametric norm at t a = 25c, and are provided for reference purposes only. unless otherwise indicated, t a = 25c. parameter min. typ. max. units conditions operating voltage range v cc 0.9 6.0 v supply current i cc 1.0 3.0 a v cc =v th +0.1v reset threshold v th 2.265 2.3 2.335 v t a =+25c 2.254 2.346 ? t a =-40c to 85c 2.561 2.6 2.639 t a =+25c 2.548 2.652 ? t a =-40c to 85c 2.857 2.9 2.944 t a =+25c 2.842 2.958 ? t a =-40c to 85c 3.054 3.1 3.147 t a =+25c 3.038 3.162 ? t a =-40c to 85c 4.334 4.4 4.466 t a =+25c 4.312 4.488 ? t a =-40c to 85c 4.531 4.6 4.669 t a =+25c 4.508 4.692 ? t a =-40c to 85c v cc reset delay v trip 20 s v cc =v th to (v th + 0.1v), v th =3.1v reset active timeout period t rp 140 230 560 ms t a =+25c 100 1030 ? t a =-40c to 85c reset output voltage v oh 0.8v cc v v cc =v th - 0.1v, i source = 1.2ma reset output voltage v ol 0.3 v cc =v th + 0.1v, i sink = 1.2ma reset output voltage v oh 0.8v cc v v cc =v th + 0.1v, i source = 1.2ma reset output voltage v ol 0.3 v cc =v th - 0.1v, i sink = 1.2ma note 1: reset output is for sp809; reset output is for sp810.
s s p p 8 8 0 0 9 9 / / s s p p 8 8 1 1 0 0 3 3 p p i i n n m m i i c c r r o o p p r r o o c c e e s s s s o o r r s s u u p p e e r r v v i i s s o o r r c c i i r r c c u u i i t t ? 2011 exar corporation 3/8 rev. 2.0.0 block diagram fig. 2: sp809 / sp810 block diagram pin assignment fig. 3: sp809 / sp810 pin assignment pin description name pin number description gnd 1 ground signal reset 2 active low output pin. reset output remains high while vcc is below the reset threshold reset active high output pin. reset output remains high while vcc is below the reset threshold v cc 3 supply voltage
s s p p 8 8 0 0 9 9 / / s s p p 8 8 1 1 0 0 3 3 p p i i n n m m i i c c r r o o p p r r o o c c e e s s s s o o r r s s u u p p e e r r v v i i s s o o r r c c i i r r c c u u i i t t ? 2011 exar corporation 4/8 rev. 2.0.0 ordering information part number temperature range marking package packing quantity note 1 note 2 sp809ek-l-2-3/tr -40c t a +85c n4ww sot23-3 2.5k/tape & reel lead free sp809ek-l-2-6/tr -40c t a +85c p4ww sp809ek-l-2-9/tr -40c t a +85c q4ww sp809ek-l-3-1/tr -40c t a +85c r4ww sp809ek-l-4-6/tr -40c t a +85c u4ww sp809nek-l-2-3/tr -40c t a +85c v4ww sp809nek-l-2-9/tr -40c t a +85c x4ww sp809nek-l-3-1/tr -40c t a +85c y4ww sp809nek-l-4-6/tr -40c t a +85c c5ww sp810ek-l-2-6/tr -40c t a +85c e5ww sp810ek-l-4-4/tr -40c t a +85c j5ww ?yy? = year ? ?ww? = work week ? ?x? = lot number; when applicable.
s s p p 8 8 0 0 9 9 / / s s p p 8 8 1 1 0 0 3 3 p p i i n n m m i i c c r r o o p p r r o o c c e e s s s s o o r r s s u u p p e e r r v v i i s s o o r r c c i i r r c c u u i i t t ? 2011 exar corporation 5/8 rev. 2.0.0 typical performance characteristics all data taken at t a = 25c, unless otherwise specified - schematic and bom from application information section of this datasheet. fig. 4: supply current versus temperature fig. 5: power-down reset delay versus temperature fig. 6: power-down reset delay versus temperature fig. 7: power-down reset delay versus temperature fig. 8: normalized reset threshold versus temperature fig. 9: power-up reset time-out versus temperature
s s p p 8 8 0 0 9 9 / / s s p p 8 8 1 1 0 0 3 3 p p i i n n m m i i c c r r o o p p r r o o c c e e s s s s o o r r s s u u p p e e r r v v i i s s o o r r c c i i r r c c u u i i t t ? 2011 exar corporation 6/8 rev. 2.0.0 theory of operation p will be activated at a valid reset state. these p supervisory circuits assert reset to prevent code execution errors during power- up, power-down, or brownout conditions. reset is guaranteed to be a logic low for v th >v cc >0.9v. once v cc exceeded the reset threshold, an inte rnal timer keeps reset low for the reset timeout period; after this interval, reset goes high. if a brownout condition occurs (v cc drops below the reset threshold), reset goes low. any time v cc goes below the reset threshold, the internal timer resets to zero, and reset goes low. the internal timer is activated after v cc returns above the re set threshold, and reset remains low for the reset timeout period. b enefit of h ighly a ccurate r eset t hreshold sp809/810 with specified voltage as 5v10% or 3v10% are ideal for systems using a 5v5% or 3v5% power supply. the reset is guaranteed to assert after the power supply falls below the minimum specified operating voltage range of the system ics. the pre- trimmed thresholds are reducing the range over which an undesirable reset may occur. application information n egative g oing v cc t ransients in addition to issuing a reset to the p during power-up, power-down, and brownout conditions, sp809 series are relatively resistant to short-duration negative-going v cc transient. e nsuring a v alid r eset o utput d own to v cc =0 when v cc falls below 0.9v, sp809 reset output no longer sinks current; it becomes an open circuit. in this case, high-impedance cmos logic inputs connecting to reset can drift to undetermined voltages. therefore, sp809/810 with cmos is perfect for most applications of v cc down to 0.9v. however in applications where reset must be valid down to 0v, adding a pull-down resistor to reset causes any leakage currents to flow to ground, holding reset low. i nterfacing to p with b idirectional r eset p ins the reset output on the sp809n is open drain, this device interfaces easily with ps that have bidirectional reset pins. connecting the p supervisor's reset output directly to the microcontroller's reset pin with a single pull-up resistor allows either device to assert reset. t est c ircuit fig. 10: test circuit
s s p p 8 8 0 0 9 9 / / s s p p 8 8 1 1 0 0 3 3 p p i i n n m m i i c c r r o o p p r r o o c c e e s s s s o o r r s s u u p p e e r r v v i i s s o o r r c c i i r r c c u u i i t t ? 2011 exar corporation 7/8 rev. 2.0.0 package specification 3-p in sot23
s s p p 8 8 0 0 9 9 / / s s p p 8 8 1 1 0 0 3 3 p p i i n n m m i i c c r r o o p p r r o o c c e e s s s s o o r r s s u u p p e e r r v v i i s s o o r r c c i i r r c c u u i i t t ? 2011 exar corporation 8/8 rev. 2.0.0 revision history revision date description 2.0.0 reformat of datasheet correction of package drawing for further assistance email: customersupport@exar.com exar technical documentation: http://www.exar.com/techdoc/default.aspx? e xar c orporation h eadquarters and s ales o ffices 48720 kato road fremont, ca 94538 ? usa tel.: +1 (510) 668-7000 fax: +1 (510) 668-7030 www.exar.com notice exar corporation reserves the right to make changes to the products contained in this publication in order to improve design, performance or reliability. exar corporation assumes no responsibility for the use of any circuits described herein, conveys no license under any patent or other right, and make s no representation that the circuits are free of patent infringement. charts and schedules contained here in are only for illustr ation purposes and may vary depending upon a user?s specific application. while the information in this publication has been carefully checked; no responsibility, however, is assumed for inaccuracies. exar corporation does not recommend the us e of any of its products in life support applications where the failure or malfunction of the product can reasonably be expected to cause fa ilure of the life support system or to significantly affect it s safety or effectiveness. products are not authorized for use in such applications unless exar corporation receives, in writing, assurances to its satisfaction that: (a) the risk of injury or damage has been minimized; (b) the user assumes all such risks; (c) potential liability of exar corporation is adequately protected under the circumstances. reproduction, in part or whole, without the prior written consent of exar corporation is prohibited.
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