mic809/810 microprocessor reset circuits general description the mic809 and mic810 are inexpensive microprocessor supervisory circuits that monitor power supplies in microprocessor - based systems. the function of these devices is to assert a reset if the power supply drops below a designated reset threshold level. several different reset threshold levels are available to accommodate 3v, 3.3v or 5v powered systems. the mic809 has an active - low /reset output, while the mic810 offers an active - high reset output. the reset output is guaranteed to remain asserted for a minimum of 140ms after v cc has risen above the designated reset threshold level. having a push - pull output stage, the mic809/810 does not require a pull - up resistor at the output. the mic809/810 comes in a 3 - pin sot - 23 and sc - 70 package. t he mic809 is also available with a shorter reset timeout (30ms, minimum). datasheets and support documentation are available on micrels web site at : www.micrel.com . features ? precision voltage monitor for 3v, 3.3v , o r 5v power supplies ? /reset remains valid with v cc as low as 1.4v for sot - 23 packaged part ? /reset remains valid with v cc as low as 1v for sc70 - packaged part ? typically less than 15a supply current for sot - 23 packaged part ? 5a ( typical ) supply current for sc70 - packaged part ? 140ms ( minimum ) reset pulse widths available ? available in 3 - pin sot - 23 and sc - 70 package applications ? portable equipment ? intelligent instruments ? critical microprocessor power monitoring ? printers/computers ? controllers typical applicati on micrel inc. ? 2180 fortune drive ? san jose, ca 95131 ? usa ? tel +1 (408) 944 - 0800 ? fax + 1 (408) 474 - 1000 ? http://www.micrel.com july 6, 2015 revision 3.0 downloaded from: http:///
micrel, inc. mic809/810 ordering information ( 1 ) part number marking ( 2 ) threshold voltage (v) operating temperature range lead finish 3- pin sot - 23 3- pin sc - 70 mic809luy mic809ly c3 il 4.63 C 40 c to +85 c pb-free mic809muy mic809myc3 im 4.38 C 40 c to +85 c pb-free mic809juy mic809jyc3 ij 4 .00 C 40 c to +85 c pb-free mic809tuy mic809tyc3 it 3.08 C 40 c to +85 c pb-free mic809suy mic809syc3 is 2.93 C 40 c to +85 c pb-free mic809ruy mic809ryc3 ir 2.63 C 40 c to +85 c pb-free mic810luy mic810 lyc3 jl 4.63 C 40 c to +85 c pb-free mic810 muy mic810 myc3 jm 4.38 C 40 c to +85 c pb-free mic810 juy mic810 jyc3 jj 4.00 C 40 c to +85 c pb-free mic810 tuy mic810 tyc3 jt 3.08 C 40 c to +85 c pb-free mic810 suy mic810 syc3 js 2.93 C 40 c to +85 c pb-free mic810 ruy mic810 ryc3 jr 2.63 C 40 c to +85 c pb-free note: 1. all devices available in tape and reel only (order entry pn, add tr, i.e., mic809luy tr) . standard/full reel quantity is 3,000 pieces. reel diam eter is 7in, hub diameter is 2in, and width is 8mm. 2. underbar symbol (__) may not be to scale. pin configuration 3- pin mic809 sot - 23 3- pin mic809 sc - 70 (top view) 3- pin mic810 sot - 23 3- pin mic810 sc - 70 (top view) july 6, 2015 2 rev ision 3.0 downloaded from: http:///
micrel, inc. mic809/810 pin description pin number mic809 pin number mic810 pin name pin name 1 1 gnd ic ground pin. 2 n/a /reset /reset goes low if v cc falls below the reset threshold and remains asserted for one reset timeout period (140ms min.) after v cc exceeds the reset threshold. n/a 2 reset reset goes h igh if v cc falls below the reset threshold and remains asserted for one reset timeout period (14 0ms, minimum ) after v cc exceeds the reset threshold. 3 3 vcc power supply input. part numbering conventions mic809 sot - 23 mic809 sc - 70 july 6, 2015 3 rev ision 3.0 downloaded from: http:///
micrel, inc. mic809/810 july 6, 2015 4 revision 3.0 absolute maximum ratings ( 3 ) terminal voltage (v cc ) ................................. C0.3v to +6.0v input current (v cc ) ...................................................... 20ma output current (/ reset, reset) .............................. 20ma lead temperature (sol dering, 10s) ............................ 300c storage temperature (t s ) ........................... C65c to 150c rate-of-rise (v cc ) ................................................... 100v/ s esd rating ( 5 ) .................................................... 3kv (sc-70) operating ratings ( 4 ) operating temperature range mic809 ................................................. C40c to +85c mic810 ................................................. C40c to +85c power dissipation (t a = +70c) ............................... 320mw electrical characteristics ( 6 ) for typical values, v cc = 5v for mic8_l/m/j, v cc = 3.3v for mic8_s/t, v cc = 3v for mic8_r; t a = 25c. bold values indicate C40c to t a +85c; unless otherwise noted. symbol parameter condition min. typ. max. units v cc operating voltage range t a = 0c to 70c (sot-23) 1.4 5.5 v t a = C40c to 85c (sot-23) 1.6 5.5 v t a = C40c to 85c (sc70) 1 5.5 v i cc supply current mic809l/m/j, mic 810l/m/j (sot-23) 9 15 a mic809l/m/j, mic 810l/m/j (sc-70) 5 15 v cc <3.6v, mic809r/s/t, mic810r/s/t (sot-23) 6 10 v cc <3.6v, mic809r/s/t, mic810r/s/t (sc-70) 5 10 v th reset voltage threshold mic809l, mic810l 4.50 4.63 4.75 v mic809m, mic810m 4.25 4.38 4.50 mic809j, mic810j 3.89 4.00 4.10 mic809t, mic810t 3.00 3.08 3.15 mic809s, mic810s 2.85 2.93 3.00 mic809r, mic810r 2.55 2.63 2.70 t rst reset timeout period 140 240 560 ms v oh /reset output voltage (mic809) i source = 800a, mic809l/m/j v cc C 1.5v v i source = 500a, mic809r/s/t 0.8 v cc notes: 3. exceeding the absolute maximum ratings may damage the device. 4. the device is not guaranteed to fu nction outside its operating ratings. 5. devices are esd sensitive. handling prec autions are recommended. human body model, 1.5k ? in series with 100pf. 6. specification for packaged product only. downloaded from: http:///
micrel, inc. mic809/810 electrical characteristics ( 6 ) (continued) for typical values, v cc = 5v for mic8_l/m/j, v cc = 3.3v for mic8_s/t, v cc = 3v fo r mic8_r; t a = 25c. bold values indicate C 40c to t a +85 c ; unless otherwise noted. symbol parameter condition min . typ . max . units v ol /reset output voltage ( mic809 ) v cc = v th (minimum), i sink = 3.2ma, mic809l/m/j 0.4 v v cc = v th (minimum)., i sink = 1.2ma, mic809r/s/t 0.3 v cc >1.4v, i sink = 50 a, t a = 0c to +70c 0.3 v cc = 1v, i sink = 50 a, t a = C 40c to +85c (sc- 70) 0.3 v cc >1.6v, i sink = 50 a, t a = C 40c to +85c 0.3 v oh reset output voltage ( mic810 ) 1.8v < v cc < v th (minimum) , i source = 150 a 0.8 v cc v v ol reset output voltage ( mic810 ) i sink = 3.2ma, mic810l/m/j 0.4 v i sink = 1.2ma, mic810r/s/t 0.3 timing diagram reset timing diagram july 6, 2015 5 rev ision 3.0 downloaded from: http:///
micrel, inc. mic809/810 functional diagram july 6, 2015 6 rev ision 3.0 downloaded from: http:///
micrel, inc. mic809/810 application information micro processor reset the /reset (or reset) pin is asserted whenever v cc falls below the reset threshold voltage. the /reset pin remains asserted for a period of 140ms after v cc has risen above the reset threshold voltage. the reset function ensures the microprocessor is properly reset and powers up in a known condition after a power failure. /reset will remain valid with v cc as low as 1.4v (1v for sc - 70 package). v cc transients the mic809/810 are relatively immune to negative - going v cc glitches below the reset threshold. typically, a negative - going transient 125mv below the reset threshold with duration of 2 s or less (sc70 package) will not cause a reset. interfacing to bidirectional reset pins the mic809/810 can interface with ps with bidirectional reset pins by connecting a 4.7k ? resistor in series with the mic809/810 output and the p reset pin. /reset valid at low voltage a resistor can be added from the /reset pin to ground to ensure the /reset output remains low with v cc down to 0v. a 100k ? resistor connected from the /reset to ground is recommended. the resistor should be small enough to pull - down any stray leakage currents and large enough not to load the reset output ( figure 1 ). figure 1 . reset valid to v cc = 0v july 6, 2015 7 rev ision 3.0 downloaded from: http:///
micrel, inc. mic809/810 package information and recommended landing patterns ( 7 ) 3-pin sot - 23 (u) note: 7. package information is correct as of the publication date. for updates and most current information, go to www.micrel.com . july 6, 2015 8 rev ision 3.0 downloaded from: http:///
micrel, inc. mic809/810 package information and recommended landing patterns ( 7 ) (continued) 3- pin sc - 70 ( c3 ) july 6, 2015 9 rev ision 3.0 downloaded from: http:///
micrel, inc. mic809/810 micrel, inc. 2180 fortune drive san jose, ca 95131 usa tel +1 (408) 944 - 0800 fax +1 (408) 474 - 1000 web http://www.micrel.com micrel, inc. is a leading global manufacturer of i c solutions for the worldwide high performance linear and power, lan, and timing & communications markets. the companys products include advanced mixed - signal, analog & power semiconductors; high - performance communication, clock management, mems - based clo ck oscillators & crystal - less clock generators, ethernet switches, and physical layer transceiver ics. company customers include leading manufacturers of enterprise, consumer, industrial, mobile, telecommunications, automotive, and comp uter products. co rporation headquarters and state - of - the - art wafer fabrication facilities are located in san jose, ca, with regional sales and support offices and advanced technology design centers situated throughout the a mericas, europe, and asia. additionally, the company maintains an extensive network of distributors and reps worldwide. micrel makes no representations or warranties with respect to the accuracy or completenes s of the inf ormation furnished in this data sh eet. this information is not intended as a warranty and micrel does not assume responsibility for its use. micrel reserves the right to change circuitry, specifications and descriptions at any time without notice. no license, whether express, implied, ar ising by estoppel or otherwise, to any intellectual property rights is granted by this document. e xcept as provided in micrels terms and conditions of sale for such products, micrel assumes no li ability whatsoever, and micrel disclaims any express or implied warranty relating to the sale and/or use of mi crel products including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright , or other intellectual property right. micrel product s are not designed or authorized for use as components in life support appliances, devices or systems wher e malfunction of a product can reasonably be expected to result in personal injury. life support devices or systems are devices or sy stems that (a) are intended for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. a purchasers use or sale of micrel products for use in life support appliances, devices or systems is a purchasers own risk and purchaser agrees to fully indemnify micrel for any damages resulting from such use or sale. ? 20 04 micrel, incorporated. july 6, 2015 10 rev ision 3.0 downloaded from: http:///
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