cat885 ? catalyst semiconductor, inc. 1 doc. no. md-3028 rev. a characteristics subject to change without notice five-channel power supply supervisors features ? five-channel supply voltage detection ? 2 v dd inputs allow monitoring of +5.0v, +3.3v, +3.0v, +2.5v or +1.8v supplies ? 3 adjustable voltage inputs allow monitoring supplies > 0.6v ? 70ms minimum reset delay ? manual reset capability ? reset signals valid down to v dd = 1v ? accurate < 2% voltage threshold ? power-supply transients suppressed ? low 2a maximum supply current at 5v ? rohs-compliant msop package applications ? telecom & datacom systems ? routers & servers ? data storage equipment ? set-top boxes ? multi-voltage systems description the cat885 is a five-channel power supply supervisory circuit with high reset thereshold accuracy and very low power consumption. the device features an open-drain output, active-low function with manual reset to perform basic system reset and monitoring functions for a wide range of electronic products. the cat885 monitors five system voltages by maintaining a reset output active until al l the power supply voltages exceed the specified trip values. the device then maintains the reset output in an active condition until the internal timer times out, which allows the system power supplies to stabilize. two of the five voltage detectors are factory set for standard supplies, while the threshold voltages of the third, fourth, and fifth volt age monitors can be adjusted for specific system design requirements using external resistors. the cat885 lowers system costs and saves board space by integrating five channels into a single, small msop 8-lead package. for ordering information details see page 7. pin configuration typical application msop 8-lead (z) (top view) mr 1 8 rst v dd 2 7 v5mon v dd2 3 6 v4mon v ss 4 5 v3mon cat885 see page 2 for pin functions rst mr pb reset signal v3mon v4mon v5mon cat885 v dd v dd2 v ss
cat885 doc. no. md-3028 rev. a 2 ? catalyst semiconductor, inc. characteristics subject to change without notice functional block diagram pin functions pin # pin function 1 mr active-low manual reset input with internal pull-up resistor 2 v dd chip supply, first preset under-voltage detector input 3 v dd2 second preset under-voltage detector input 4 v ss ground 5 v3mon adjustable third under-voltage detector input 6 v4mon adjustable fourth under-voltage detector input 7 v5mon adjustable fifth under-voltage detector input 8 rst active-low open drain reset output, use external resistor rst mr reset signal v3mon v4mon v dd v ss v dd2 v dd v ref pb v dd v ref v ref v ref v5mon v ref por
cat885 ? catalyst semiconductor, inc. 3 doc. no. md-3028 rev. a characteristics subject to change without notice absolute maximum ratings (1) parameters ratings units temperature under bias -40 to +125 oc voltage on any pin with respect to v ss -1.0 to +7.0 v dc output current 5 ma thermal resistance ? ja for msop package (2) 145 c/w recommended operating conditions parameters ratings units operating temperature range (i ndustrial) -40 to +85 oc storage temperature -65 to +150 oc lead soldering temperature (10 seconds) +300 oc electrical characteristics over the recommended operating condit ions unless otherwise specified. symbol parameter conditions min typ. max units v dd supply voltage range 1.5 5.5 v i dd1 v dd supply current v dd = 5.0v 2 9 a i dd2 v dd2 input current v dd2 = 3.3v 0.5 3 a i ddx v3, v4, v5mon input current v3, v4, v5mon = 1.0v 15 50 na voltage thresholds cat885lx 4.55 4.63 4.72 v v th1 fixed voltage trip point for v dd cat885sx 2.81 2.87 2.92 v v th1 = 4.63v 50 mv v th1hyst hysteresis of v th1 v th1 = 2.87v 30 mv cat885xt 3.02 3.08 3.13 v cat885xs 2.90 2.95 3.01 v cat885xz 2.29 2.33 2.37 v v th2 fixed voltage trip point for v dd2 cat885xa 1.65 1.68 1.71 v v th2 = 3.08v 40 mv v th2 = 2.95v 30 mv v th2 = 2.33v 25 mv v th2hyst hysteresis of v th2 v th2 = 1.68v 20 mv v ref v3mon, v4mon, v5mon adj. reset threshold voltage v th for v3, v4, v5mon 0.585 0.598 0.611 v v refhyst hysteresis voltage 3 mv notes: (1) stresses above those listed under ?absol ute maximum ratings? may cause permanent damage to the device. these are stress ra tings only and functional operation of the devices at these or any other conditions outside of those listed in the operational sectio ns of this specification is not implied. exposure to any absolute maximum rating for extended pe riods may affect device performance and re liability. (2) ja is measured with the component mounted on a high e ffective thermal conductivity test board in free air.
cat885 doc. no. md-3028 rev. a 4 ? catalyst semiconductor, inc. characteristics subject to change without notice electrical characte ristics (continued) symbol parameter conditions min typ. max units reset v dd 3.3v, sinking 2.5ma 0.05 0.40 v v ol reset output voltage low v dd < 3.3v, sinking 1.5ma 0.05 0.40 v t rpd v th to reset asserted delay 1 6 s t pd por timeout delay 70 120 240 ms c load load capacitance on reset pin 5 pf manual reset v thl mr input voltage low 0.8 v v thh mr input voltage high v dd - 0.6 v t pw mr minimum pulse width 1 s r in internal pull-up resistor 8 16 k ? operation the cat885 is designed to monitor critical supply voltages in line driven and battery powered microprocessor systems, providing supply voltage supervision, power on reset control and manual reset assertion. these features along with excellent threshold accuracy and low power consumption make the cat885 device suitable for a wide variety of applications needing multi-voltage monitoring. during normal operation, the cat885 monitors the voltage levels of v dd , v2mon, v3mon, v4mon, and v5mon. if the voltage on any of these five inputs falls below their respective voltage trip points, a reset is asserted (rst = low) to prevent the microprocessor from operating during a power failure or brownout condition. this reset si gnal remains low until the voltages exceeds the voltage threshold settings for the reset time delay period t pd . cat885 allows users to adjust the minimum voltage sense level for three of the five monitored voltages. for example, the user can adjust the voltage input trip point for v 3mon , v 4mon and v 5mon inputs. this is done by connecting an external resistor divider network to the v xmon pin in order to set the trip point to a voltage above 600mv. resistors r 1 and r 2 in figure 1 are selected by the formula: v trip = 0.6v x (r 1 + r 2 ) / r 2 . figure 1. cat885 programming trip voltage v2mon vxmon vdd cat885 r 1 r 2 gnd
cat885 ? catalyst semiconductor, inc. 5 doc. no. md-3028 rev. a characteristics subject to change without notice power on reset (por) applying power to the cat885 activates a por circuit which activates the reset output (active low). at power-up por prevents the system microprocessor from starting to operate with insufficient voltage and prior to stabilization of the clock oscillator. it ensures that operation is precluded until internal registers are properly loaded, fpga?s have downloaded their configuration data prior and all system power supplies are above minimum operating levels and stable. the reset signal remains active until v dd rises above the minimum preset voltage level for time period t pd . manual reset the manual-reset input (mr ) allows the user to trigger a reset by using a push-button switch or by electronically driving the input low. the mr input is an active low debounced input. reset is asserted anytime the mr pin is pulled low to less than 100mv for the minimum mr pulse width or longer. the reset output remains asserted low for t pd , typically 120ms and then is released. figures 2 and 3 illustrate the cat885?s operation and rst output response times. figure 2. power supply monitoring diagram figure 3. auxillary voltage monitoring diagram v dd/ v dd2 0 mr 0 rst 0 t pd v th1/2 1v t pd t pd >t pw t rpd t rpd v mon 0 0 rst v th t pd t rpd
cat885 doc. no. md-3028 rev. a 6 ? catalyst semiconductor, inc. characteristics subject to change without notice package outline drawing msop 8-lead 3 x 3mm (z) (1)(2) notes: (1) all dimensions are in millimeters. angles in degrees. (2) complies with jedec standard mo-187. for current tape and reel information, download the pdf file from: http: / / www.catsemi.com/documents/tapeandreel.pdf. e1 e a2 a1 e b d c a top view side view end view l1 l2 l detail a detail a symbol min nom max a1.10 a1 0.05 0.10 0.15 a2 0.75 0.85 0.95 b0.22 0.38 c0.13 0.23 d 2.90 3.00 3.10 e 4.80 4.90 5.00 e1 2.90 3.00 3.10 e 0.65 bsc l 0.40 0.60 0.80 l1 0.95 ref l2 0.25 bsc 0o 6o
cat885 ? catalyst semiconductor, inc. 7 doc. no. md-3028 rev. a characteristics subject to change without notice example of ordering information (1) ordering information part number v dd v dd2 package cat885zi-st-gt3 2.87v 3.08v msop cat885zi-ss-gt3 2.87v 2.95v msop CAT885ZI-SZ-GT3 2.87v 2.33v msop cat885zi-sa-gt3 2.87v 1.68v msop cat885zi-lt-gt3 4.63v 3.08v msop cat885zi-ls-gt3 4.63v 2.95v msop cat885zi-lz-gt3 4.63v 2.33v msop cat885zi-la-gt3 4.63v 1.68v msop notes: (1) all packages are rohs-compliant (lead-free, halogen-free). (2) the standard finish is nipdau. (3) the device used in the above example is a cat885 zi-ls-gt3 (msop, industrial temperature, 4.63v (v dd ) and 2.95v (v dd2 ) detection levels, nipdau, tape & reel, 3,000/reel). (4) for additional detection voltage, package and temperature options , please contact your nearest catalyst semiconductor sales office. prefix device # suffix cat 885 z i -l s -g t3 company id package z: msop temperature range i = industrial (-40oc to 85oc) product numbe r 885 tape & reel t: tape & reel 3: 3 , 000/reel lead finish g:nipdau v oltage detection v dd2 level t = 3.08v s = 2.95v z = 2.33v a = 1.68v v oltage detection v dd level s = 2.87v l = 4.63v for product top mark codes, click here: http://www.catsemi.com/techsupport/producttopmark.asp
revision history date rev. reason 05-may-08 a initial release catalyst semiconductor, inc. corporate headquarters 2975 stender way santa clara, ca 95054 phone: 408.542.1000 document no: md-3028 fax: 408.542.1200 revision: a www.catsemi.com issue date: 05/05/08 copyrights, trademarks and patents ? catalyst semiconductor, inc. trademarks and register ed trademarks of catalyst semiconductor include each of the following: adaptive analog?, beyond memory?, dpp?, ezdim?, ldd?, minipot?, quad-mode? and quant um charge programmable? catalyst semiconductor has been issued u. s. and foreign patents and has patent applicat ions pending that protect its products. catalyst semiconductor makes no warranty, representation or guar antee, express or implied, regarding the suitability of its products for any particular purpose, nor that the use of its pro ducts will not infringe its intellectual property rights or the rights of third parties with respect to any particular use or application and specifically disclaims any and all liability aris ing out of any such use or application, including but not limited to, consequential or incidental damages. catalyst semiconductor products are not designed, intended, or authorized for use as components in systems intended for surgica l implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the catalyst semiconduct or product could create a situation where personal injury or death may occur. catalyst semiconductor reserves the right to make changes to or discontinue any produ ct or service descr ibed herein without not ice. products with data sheets labeled "advance information" or "preliminary" and other products described herein may not be in pr oduction or offered for sale. catalyst semiconductor advises customers to obtain the current version of the rele vant product informati on before placing order s. circuit diagrams illustrate typical semiconductor applications and may not be complete.
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