aat3526/7/8 micropower? supervisory circuit with manual reset typical application *aat3528 only aat3526 aat3527 aat3528 p v mr cc vcc vcc reset (reset) gnd gnd reset input 100k (nominal) * 3526.2006.03.1.6 1 general description the aat3526/7/8 powermanager products are members of analogictech's total power manage- ment ic? (tpmic?) product family. these micro- processor reset circuits are ideal for monitoring volt- age supplies in portable systems, where extended battery life is critical. they provide a reliable, low- cost solution by eliminating external components. the aat3526/7/8 products operate by monitoring the system power supply voltage. when the input voltage drops below a fixed threshold, the device asserts a reset signal for a minimum of 150ms after v cc has risen back above the fixed threshold. they are guaranteed to operate down to 1.2v and designed to ignore fast line transients appearing on v cc . the aat3526/7/8 series is available with three output stage versions: aat3526 push-pull active low output; aat3527 push-pull active high output; and aat3528 open drain active low output. the quiescent supply current is extremely low, typically 1a, making this device ideal for portable battery- operated equipment. aat3526/7/8 devices are available in a pb-free, 4-pin sot143 package and are specified over the -40c to +85c operating temperature range. features ? input voltage range: 1.2v to 5.5v ? operation down to 1.2v ? extremely low quiescent current: less than 2a ? high accuracy detection threshold: 1.5% ? monitor power supply voltages ? fixed thresholds from 2.2v to 4.6v ? minimum 150ms reset pulse width with fast delay time <20s ? debounced manual reset input ? available output configurations: ? open-drain output ? cmos active high output ? cmos active low output ? temperature range: -40c to +85c ? 4-pin sot143 package ? 4kv esd rating applications ? cell phones ? embedded systems ? intelligent instruments ? notebook computers ? portable electronics powermanager ?
pin descriptions aat3526, 3527, 3528 (sot143) part number descriptions pin configuration sot143 (top view) mr 3 vcc (reset) reset gnd 1 2 4 part number output type aat3526 reset output push pull active low with delay aat3527 reset output push pull active high with delay aat3528 reset output open drain active low with delay pin # symbol function 1 gnd ground connection. reset reset output remains high while v cc is below the reset threshold 2 (aat3527) and remains so for a minimum of 150ms after v cc raises above the reset threshold. reset reset output remains low while v cc is below the reset threshold (aat3526, and remains so for a minimum of 150ms after v cc raises above the aat3528) reset threshold. 3 mr manual reset active low input. a logic low signal on mr asserts a reset condition. asserted reset continues as long as mr is low and for a minimum of 150ms after mr returns high. 4 vcc supply voltage (+1.2v to +5.5v). due to extremely low operating current, it is recommended to place a 10nf capacitor between v cc and gnd. aat3526/7/8 micropower? supervisory circuit with manual reset 2 3526.2006.03.1.6
aat3526/7/8 micropower? supervisory circuit with manual reset 3526.2006.03.1.6 3 absolute maximum ratings 1 t a = 25c, unless otherwise noted. thermal information 2 symbol description value units ja maximum thermal resistance 200 c/w p d maximum power dissipation 320 mw symbol description value units v cc v cc to gnd -0.3 to 5.5 v v mr mr to gnd -0.3 to v cc + 0.3 v v reset reset to gnd (push-pull output) -0.3 to v cc + 0.3 v reset to gnd (open drain output) -0.3 to 5.5 i vcc , i mr maximum continuous input current 20 ma i reset reset/reset current 20 ma dvcc/dt rate of rise of v cc 100 v/s t j operating junction temperature range -40 to 150 c t lead maximum soldering temperature (at leads) for 10s 300 c 1. stresses above those listed in absolute maximum ratings may cause permanent damage to the device. functional operation at c ondi- tions other than the operating conditions specified is not implied. only one absolute maximum rating should be applied at any one time. 2. mounted on an fr4 board.
aat3526/7/8 micropower? supervisory circuit with manual reset 4 3526.2006.03.1.6 electrical characteristics v in = 5v, t a = -40c to +85c, unless otherwise noted. typical values are t a = 25c, v cc = 5v for 4.63/4.38v ver- sions, v cc = 3.3v for 3.08/2.93v versions, v cc = 3.0v for 2.63v versions, and v cc = 2.5v for 2.32/2.2v versions. symbol description conditions min typ max units v cc operation voltage t a = 0c to +70c 1.0 5.5 v t a = -40c to +85c 1.2 5.5 i q quiescent current v cc = 5.5v 1.05 3 a v cc = 3v 0.85 2 v th reset threshold 1 t a = 25c v th - 1.5% v th v th + 1.5% v t a = -40c to +85c v th - 2.5% v th v th + 2.5% ? v th /c reset threshold tempco 40 ppm/c t p reset propagation delay v cc = v th to (v th - 100mv) 15 s t rdy reset active timeout period 150 250 400 ms t mr mr minimum pulse width 10 s mrgi mr glitch immunity 100 ns t md mr to reset propagation delay 0.5 s v ih mr input threshold (high) v cc = v th(max) , v th 4.38v 2.3 v v cc = v th(max) , v th < 4.38v 0.7 v cc v il mr input threshold (low) v cc = v th(max) , v th 4.38v 0.8 v v cc = v th(max) , v th < 4.38v 0.25 v cc r mr mr pull-up resistance 30 65 90 k ? i sink = 1.2ma, v cc = v th(min) , 0.3 v ol reset low output voltage v th 3.08v, reset asserted v aat3526, aat3528 i sink = 3.2ma, v cc = v th(min) , 0.4 v th > 3.08v, reset asserted i source = 800a, v th > 3.08v, v cc - 1.5 reset high output voltage v cc > v th (max) v oh aat3526 i source = 500a, v th 3.08v, 0.8 v cc v v cc > v th (max) i sink = 1.2ma, v cc > v th (max) 0.3 v ol reset low output voltage v th 3.08v, reset not asserted v aat3527 i sink = 3.2ma, v cc > v th (max) 0.4 v th > 3.08v, reset not asserted i source = 500a, v cc > 2.1v, 0.8v cc v oh reset high output voltage reset asserted v aat3527 i source = 50a, v cc > 1.2v, 0.8v cc reset asserted i doff reset leakage current, v cc > v th 1a aat3528 1. see ordering information for factory-trimmed reset thresholds.
aat3526/7/8 micropower? supervisory circuit with manual reset 3526.2006.03.1.6 5 typical characteristics maximum transient duration vs. reset threshold overdrive 0 50 100 150 200 250 300 350 400 1 10 100 1000 reset threshold overdrive, v th - v cc (mv) maximum transient duration (s) power-down reset propagation delay vs. temperature 0 5 10 15 20 25 30 -40 -20 0 20 40 60 80 temperature ( c) reset propagation delay (s) v od = 10mv v od = 100mv power-up reset timeout vs. temperature 160 180 200 220 240 260 280 300 320 -40 -20 0 20 40 60 80 100 temperature ( c) power-up reset timeout (ms) normalized reset threshold vs. temperature 0.997 0.998 0.999 1.000 1.001 1.002 1.003 -40 -20 0 20 40 60 80 temperature ( c) normalized threshold supply current vs. temperature 0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 -40 -20 0 20 40 60 80 temperature ( c) supply current (a) v cc = 5v v cc = 3v
aat3526/7/8 micropower? supervisory circuit with manual reset 6 3526.2006.03.1.6 functional description general during start-up, the reset pin on a microprocessor ensures that it is fully reset and starts up in a known condition. the aat3526/7/8 series of microproces- sor reset devices monitor the supply voltage to a microprocessor and assert a reset signal whenever the v cc voltage falls below a factory-programmed threshold. this threshold is accurate within 1.5% at 25oc and within 2.5% over the entire operating temperature range. the reset signal remains asserted for a minimum of 150ms after v cc has risen above the threshold, as shown in figure 1. functional block diagram reset generator + timer oscillator vcc gnd reset (reset) mr v ref figure 1: reset timing diagram. v cc v th v th v th t rdy t rdy
applications information reset output options the aat3528 has an active low open drain output and the aat3526/7 have a push-pull output. the aat3528 may be used in multiple voltage systems with an external pull-up resistor. this allows the aat3528 to interface to microprocessors with high- er supply voltages up to 5.5v (figure 2). in the event of a power-down or brown-out condition, the reset signal remains valid until the v cc drops below 1.2v. to ensure validity down to ground, an external 100k ? resistor should be connected between the reset output and gnd. manual reset input a logic low signal on mr asserts a reset condition. reset continues to be asserted as long as mr is low and for a minimum of 150ms after mr returns high. this input is internally pulled up to v cc via a 65k ? resistor, so leaving the pin unconnected is accept- able if the manual reset function is not needed. the mr input is internally debounced which allows the use of a mechanical switch. it should be a normally- open momentary switch connected from mr to gnd. additionally, the mr pin can be driven from ttl, cmos, or open drain logic outputs. supply voltage transient behavior in some cases, fast negative transients of short duration can appear on the v cc power supply. the aat3526/7/8 series devices provide some immunity to line transients which can generate invalid reset pulses. figure 1 shows typical behavior to short duration pulses versus reset comparator over- drive. as shown in the maximum transient duration vs. reset threshold overdrive graph, when the tran- sient voltage becomes larger, the time allowed before asserting a reset becomes shorter (e.g., typ- ically a transient of 100mv below the reset threshold would have to present for more than 50 s to cause a reset). immunity can be increased by the addition of a small bypass capacitor of 0.1f connected as close to the v cc pin as possible. aat3526/7/8 micropower? supervisory circuit with manual reset 3526.2006.03.1.6 7 figure 2: using recommended bypass capacitor. figure 3: using aat3528 open drain output with multiple supplies. aat3528 5v system +3.3v vcc vcc reset 100k gnd gnd reset input mr +5.0v *aat3528 only aat3526 aat3527 aat3528 p v 0.1 f mr cc vcc vcc reset (reset) gnd gnd reset input 100k (nominal) *
aat3526/7/8 micropower? supervisory circuit with manual reset 8 3526.2006.03.1.6 ordering information and factory-trimmed reset thresholds 1 all analogictech products are offered in pb-free packaging. the term ?pb-free? means semiconductor products that are in compliance with current rohs standards, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. for more information, please visit our website at http://www.analogictech.com/pbfree. reset threshold voltage, v th (v) ordering t a = 25c t a = -40 c to +85 c part number 2 marking 3 min typ max min max aat3526icx-2.32-200-t1 noxyy aat3527icx-2.32-200-t1 2.285 2.320 2.355 2.262 2.378 aat3528icx-2.32-200-t1 aat3526icx-2.63-200-t1 dnxyy aat3527icx-2.63-200-t1 2.591 2.630 2.669 2.564 2.696 aat3528icx-2.63-200-t1 drxyy aat3526icx-2.93-200-t1 doxyy aat3527icx-2.93-200-t1 dqxyy 2.886 2.930 2.974 2.857 3.003 aat3528icx-2.93-200-t1 fqxyy aat3528icx-3.00-200-t1 fixyy 2.955 3.000 3.045 2.925 3.075 aat3526icx-3.08-200-t1 eqxyy aat3527icx-3.08-200-t1 fhxyy 3.034 3.080 3.126 3.003 3.157 aat3528icx-3.08-200-t1 fjxyy aat3526icx-4.38-200-t1 gcxyy aat3527icx-4.38-200-t1 hlxyy 4.314 4.380 4.446 4.271 4.490 aat3528icx-4.38-200-t1 aat3526icx-4.63-200-t1 dpxyy aat3527icx-4.63-200-t1 hmxyy 4.561 4.630 4.699 4.514 4.746 aat3528icx-4.63-200-t1 1. contact local sales office for custom trimmed options. 2. sample stock is generally held on all part numbers listed in bold . 3. xyy = assembly and date code.
package information sot143 all dimensions in millimeters. 2.37 0.27 0.925 0.175 1.30 0.10 1.01 0.21 1.92 bsc 2.92 0.12 0.20 bsc 0.075 0.075 0.40 0.1 3 0.69 ref 0.825 0.065 0.15 0.07 4 4 0.50 0.10 aat3526/7/8 micropower? supervisory circuit with manual reset 3526.2006.03.1.6 9 advanced analogic technologies, inc. 830 e. arques avenue, sunnyvale, ca 94085 phone (408) 737-4600 fax (408) 737-4611 ? advanced analogic technologies, inc. analogictech cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in an analogictech pr oduct. no circuit patent licenses, copyrights, mask work rights, or other intellectual property rights are implied. analogictech reserves the right to make changes to their products or specifi cations or to discontinue any product or service without notice. customers are advised to obtain the latest version of relevant information to verify, before placing orders, that information b eing relied on is current and complete. all products are sold subject to the terms and conditions of sale supplied at the time of order acknowledgement, including those pertaining to warran ty, patent infringement, and limitation of liability. analogictech warrants performance of its semiconductor products to the specifications applicable at the time of sale in accordance with anal ogictech?s standard warranty. testing and other quality con- trol techniques are utilized to the extent analogictech deems necessary to support this warranty. specific testing of all param eters of each device is not necessarily performed.
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