ts809/810/809r/810r 1-6 2003/12 rev. b ts809/ 810/ 809r/ 810r microprocessor reset circuit pin assignment: ts809/810 1. gnd 2. reset (reset) 3. vcc pin assignment: ts809r/810r 1. reset (reset) 2. gnd 3. vcc threshold voltage option from 2.63v ~ 4.63v general description the ts809/810/809r/810r are microprocessor (p) supervisory circuit used to monitor the power supplies in p and digital systems. they provide excellent circuit reliability and low cost by eliminating external components and adjustments when used with +5v, +3.3v, +3.0v powered circuits. these circuits perform a single function: they assert a reset signal whenever the vcc supply voltage declines below a preset threshold, keeping it asserted for at least 140ms after vcc has risen above the reset threshold. reset thresholds suitable for operation with a variety of supply voltages are available. the ts809/810/809r/810r have push pull outputs. the ts809/809r have an active low reset output, while the ts810/810r has an active high reset output. the reset comp arator is designed to ignore fast transients on vcc, and the output guaranteed to be in the correct logic state for vcc down to 1v. low supply correct makes the ts809/810/809r/810r ideal for use in portable equipment. the ts809/810/809r/810r is available in a 3-pin sot-23 package. features ? precision monitoring of +3v, +3.3v and +5v power supply voltage ? fully specified over temperature ? available in three output configurations ? push-pull reset low output (ts809 & ts809r) ? push-pull reset high output (ts810 & ts810r) ? 140ms min. power-on reset pulse width ? 12ua supply current ? guaranteed reset valid to vcc = +1v ? power supply transient immunity ? no external components ordering information note: x is the threshold voltage type, option as a : 4.63v b : 4.38v c : 4.00v d : 3.08v e : 2.93v f : 2.63v part no. enable function package ts809cx x active-low ts810cx x active-high ts809rcx x active-low ts810rcx x active-high sot-23 applications ? computers ? controllers ? intelligent instruments ? critical up and uc power monitoring ? portable / battery powered equipment ? automotive pin descriptions name description gnd ground reset (reset) reset output pin l: for ts809 & ts811 h: for ts809r & ts811r vcc operating voltage input
ts809/810/809r/810r 2-6 2003/12 rev. b absolute maximum rating terminal voltage (with respect to gnd) v cc - 0.3 ~ +6.0 v reset & (reset) push-pull v reset - 0.3 ~ (v cc +0.3) v input current, vcc i cc 20 ma output current, reset , (reset) i o 20 ma rate of rise, vcc v r 100 v/us continuous power dissipation (ta=+70 o c) de-rate 4mw/ o c above +70 o c p d 320 mw operating junction temperature range t op -40 ~ +105 o c storage temperature range t stg -65 ~ +150 o c lead soldering temperature (260 o c) t lead 10 s electrical characteristics ta = 25 o c, unless otherwise specified. parameter conditions sym bol min typ max unit input supply voltage ta = 0 o c ~ +70 o c v cc 1.0 5.5 v v cc 5.5v 19 60 supply current v cc 3.6v i cc 17 50 ua ts809/910/809r/810rcxa 4.56 4.63 4.7 ts809/910/809r/810rcxb 4.31 4.38 4.45 ts809/910/809r/810rcxc 3.94 4.00 4.06 ts809/910/809r/810rcxd 3.03 3.08 3.13 ts809/910/809r/810rcxe 2.89 2.93 2.97 reset threshold ts809/910/809r/810rcxf v th 2.59 2.63 2.67 v reset threshold temperature coefficient v th 30 ppm/ o c v cc to reset delay v cc = v th to (v th - 100mv) 20 us reset active timeout period ta = 0 o c ~ +70 o c t delay 100 240 380 ms v cc = v th(min), i sink =1.2ma, ts809 & ts809r 0.3 v cc = v th(min), i sink =3.2ma, 0.4 reset output voltage low v cc > 1.0v, i sink =50ua v ol 0.3 v v cc > v th(max), i source =500ua, ts809 & ts809r 0.8 v cc reset output voltage high v cc > v th(max), i source =800ua, v oh v cc ? 1.5 v v cc = v th(max), i sink =1.2ma, ts810 & ts810r 0.3 reset output voltage low v cc = v th(max), i sink =3.2ma, v ol 0.4 v reset output voltage high 1.8v < v cc < v th(min), i source =150ua, ts810 & ts810r v oh 0.8 v cc v
ts809/810/809r/810r 3-6 2003/12 rev. b function description a microprocessor?s (p?s) reset input starts the p in a know state. the ts809/810/809r/810r assert reset to prevent code-execution errors during power-up, power-down, or brownout conditions. they assert a reset signal whenever the vcc supply voltage declines below a preset threshold, keeping it asserted for at least 140ms after vcc has risen above the reset threshold. the ts809/810/809r/810r have a push-pull output stage. applications information negative-going vcc transients in addition to issuing a reset to the p during power-up, power-down, and brownout conditions, the ts809/810/809r/810r are relatively immune to short-duration negative-going vcc transients (glitches). the ts809/810/809r/810r do not generate a reset pulse. the graph was generated using a negative going pulse applied to vcc, starting 0.5v above the actual reset threshold and ending below it by the magnitude indicated (reset comparator overdrive). the graph indicates the maximum pulse width a negative going vcc transient can have without causing a reset pulse. as the magnitude of the transient increases (goes farther below the reset threshold), the maximum allowable pulse width decreases. typically, a vcc transient that goes 100mv below the reset threshold and lasts 20s or less will not cause a reset pulse. a 0.1f bypass capacitor mounted as close as possible to the vcc pin provides additional transient immunity. applications circuit ensuring a valid reset output down to vcc=0 when vcc falls below 1v, the ts809/810/809r/810r reset output no longer sink s current - it becomes an open circuit. therefore, high impedance cmos logic input connected to reset can drift to undetermined voltages. this present no problem in most applications since most p and other circuitry is inoperative with vcc below 1v.however, in applications where reset must be valid down to 0v, adding a pull down resistor to reset causes and stray leakage currents to flow to ground, holding reset low (figure 2.) r1?s value is not critical; 100k is larg e enough not to load reset and small enough to pull reset to ground. for the ts809/810/809r/810r if reset is required to remain valid for vcc<1v. benefits of highly accurate reset threshold most p supervisor ics have reset threshold voltages between 5% and 10% below the value of nominal supply voltages. this ensures a reset will not occur within 5% of the nominal supply, but will occur when the supply is 10% below nominal. when using ics rated at only the nominal supply 5%, this leaves a zone of uncertainty where the supply is between 5% and 10% low, and where the reset many or may not be asserted. timing diagram
ts809/810/809r/810r 4-6 2003/12 rev. b electrical characteristics curve figure 1. iq v.s. temperature figure 2. threshold v.s. temperature figure 3. immunity
ts809/810/809r/810r 5-6 2003/12 rev. b function block marking information part no. identification code part no. identification code part no. identification code part no. identification code ts809cxa ea ts810cxa e0 ts809rcxa eg ts810rcxa e7 ts809cxb eb ts810cxb e2 ts809rcxb eh ts810rcxb e8 ts809cxc ec ts810cxc e3 ts809rcxc ei ts810rcxc e9 TS809CXD ed ts810cxd e4 ts809rcxd ej ts810rcxd em ts809cxe ee ts810cxe e5 ts809rcxe ek ts810rcxe en ts809cxf ef ts810cxf e6 ts809rcxf el ts810rcxf ep
ts809/810/809r/810r 6-6 2003/12 rev. b sot-23 mechanical drawing d c a e b g f sot-23 dimension millimeters inches dim min max min max a 2.88 2.91 0.113 0.115 b 0.39 0.42 0.015 0.017 c 1.78 2.03 0.070 0.080 d 0.51 0.61 0.020 0.024 e 1.59 1.66 0.063 0.065 f 1.04 1.08 0.041 0.043 g 0.07 0.09 0.003 0.004
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