power management aac242/ 243 ? copyright 2010- asic advant age, inc. C aads00 012 / r127b - preliminary - oct ober 2010 1 / 8 aac242/ 243 preliminary dat a current mode pwm contoller description the aac242 and aac243 are part of aais new family of specialty products for power management applications. the aac242 and aac243 are high performance integrated circuits designed for off-line or dc to dc converters using peak current mode control. the aac24x has a current sense of 250mv in comparison to 1v for aac14x parts. in offline ac designs the startup is improved by the low start-up current of the family. the integrated soft-start function adds to the easy of using the aac24x parts in offline applications. the aac242 and aac243 are identical except for the under voltage lockout. the aac242 has uvlo on threshold of 16v and off of 10v making it easy to use in offline supplies where startup requirements for energy storage is necessary. for applications using lower supply voltages the aac243 has uvlo on of 8.4v and uvlo off of 7.6v. the aac24x family is offered in dip and smd packages. the packages are industry standards and are rohs compliant. extended temperature is standard with the aac24x family. the greater than 1a output driver is ideal for driving mosfets and low power igbts. rise and fall times are typically less that 30ns with a 1000pf load. the improvements in switching speed can provide improvements in efficiency, higher operating frequency and over current protection. the aac24x family has a minimum pulse width of 0.4% allowing operation at very low power without pulse skipping or erratic operation. the narrower pulse width capibilities enhances operation at higher frequencies and voltages. features ? low start-up current ? pulse by pulse current limiting ? on board voltage reference ? under voltage lockout with hysteresis ? simple oscillator circuit ? over voltage protection zener ? high current output driver ? less than 30ns rise and fall times ? operation to over 1mhz ? peak current mode control ? integrated soft-start function (~330 clock cycles) ? 100ns leading edge current blanking for reduced filtering ? 250mv current sense pin configuration: 8-lead dip and soic8 view of t he aac24x shown f rom t he t op. v fb 8 gnd 4 1 isense comp 5 v ref rt/ct a ac242 a ac243 v cc out downloaded from: http:///
power management aac242/ 243 ? copyright 2010- asic advant age, inc. C aads00 012 / r127b - preliminary - oct ober 2010 2 / 8 block diagram open loop test circuit maximum ratings parameter parameters units conditions min. max. supply voltage (v cc C ground) 0 30 v low impedance source v fb and i sense amp inputs -0.3 5.5 v output current 1 a power dissipation 1200 mw dip 1000 mw soic8 operating juncti on temperature 150 c operating ambient temperature -40 105 c extended industrial temp. rated devices operating ambient temperature -40 125 c automotive temp. rated devices storage temperature range -65 150 c lead temperature (10 second) 300 c soldering 0.1uf a 0.1uf 4.7k ct rt 100k 8 1 2 3 4 5 6 7 vref comp fb isense r/c gnd out vcc 1k output 1k/1w v+ 2n3904 4.7k 5k - output 6 + + 1 comp 3 isense 5.00vref 8 vcc 4 rt/ct - uvlo 34v 5vref 2r s vref 7 2 vf b 2.5v r current sensecomparator refok dvr q osc 1v 5 gnd r erroramp 11r downloaded from: http:///
power management aac242/ 243 ? copyright 2010- asic advant age, inc. C aads00 012 / r127b - preliminary - oct ober 2010 3 / 8 electrical characteristics unless otherwise stated, t=25c, vcc=15v, r t = 10k ? , c t = 3300pf. parameter parameters units conditions min. typ. max. reference section output voltage 4.95 5.00 5.05 v line regulation 6 15 mv 12v power management aac242/ 243 ? copyright 2010- asic advant age, inc. C aads00 012 / r127b - preliminary - oct ober 2010 4 / 8 parameter parameters units conditions min. typ. max. output section voltage out low 0.4 v isink = 20ma voltage out low 2.2 v isink = 200ma voltage out high 13.5 14 v isink = 20ma voltage out high 12.5 13.5 v isink = 200ma voltage out uvlo 1.1 v vcc=6v, isink = 1ma voltage output rise time 30 50 ns c l =1000pf voltage output fall time 30 50 ns c l =1000pf current output source peak 1.2 a current output sink peak 0.7 a under-voltage lockout section voltage start threshold (142) 15 16 17 v voltage start threshold (143) 7.8 8.4 9 v voltage turnoff threshold (142) 9 10 11 v voltage turnoff threshold (143) 7 7.6 8.2 v zener clamp voltage 30 34 v i cc 25ma total device section start-up supply current 0.4 0.6 ma operating supply current 11 ma the improved switching performance increases the high peak current associated with internal and external capacitances and will require careful grounding and pcb trace routing. bypass and timing capacitors should be of high quality and located carefully with short traces. the re ference capacitor must be locat ed very close to the ic with minimum trace lengths. a single point ground should be located at pin 5 ground. the use of a good ground plane is recommended. under certain conditions of high peak currents it may be advisable to isolate the vref pin from the bypass capacitor with a resistor to prevent interaction of the high current with the internal oscillator operation. charge and discharge times are given by the following formulas: t c =0.55r t c t t d =r t c t ln[(0.0063r t -2.7)/(0.0063r t -4)] frequency =( t c + t d ) -1 oscillator simplified circuit. rt 8 1 2 3 4 5 6 7 vref comp fb isense r/c gnd out vcc ct downloaded from: http:///
power management aac242/ 243 ? copyright 2010- asic advant age, inc. C aads00 012 / r127b - preliminary - oct ober 2010 5 / 8 peak current is set by the internal comparator with a fixed limit of 0.250v. raising the current sense pin (3) to 0.250v or higher will cause a termination of the output pul se regardless of the error amplifier output. the peak current is normally determined when the current sense pin exceeds the error amplifier conditioned output. peak current is determined by the formula: i sense(pk) = 0.250v/r s in some cases where leading edge switching transients exceed the 100ns blanking, a small rc filter will be required. dead/delay time verses ct ct capacitance in nf oscillator frequency as a function of rt and ct oscillator frequency in khz rt resistance in k ? delay in s rc filter 8 1 2 3 4 5 6 7 vref comp fb isense r/c gnd out vcc r c rsense downloaded from: http:///
power management aac242/ 243 ? copyright 2010- asic advant age, inc. C aads00 012 / r127b - preliminary - oct ober 2010 6 / 8 in cases where duty cycle exceeds 50% slope compensation is re quired. this can be implemented by adding a buffer transistor to the oscillator circuit and using a resistive summing circuit to provide the ramp necessary for slope compensation. shut down circuits depend on the desired function. a transistor can be used to allow control on and off of the pwm or an scr can be used to latch off the pwm. slope compensation ct 8 1 2 3 4 5 6 7 vref comp fb isense r/c gnd out vcc c 2n3904 rslope rt rsense r shutdown circuits shutdown 8 1 2 3 4 5 6 7 vref comp fb isense r/c gnd out vcc 2n3904 100k 2n3904 shutdown 100k 8 1 2 3 4 5 6 7 vref comp fb isense r/c gnd out vcc downloaded from: http:///
power management aac242/ 243 ? copyright 2010- asic advant age, inc. C aads00 012 / r127b - preliminary - oct ober 2010 7 / 8 ordering ? pn(1) ?? subgroup ?? description ?? temp. ? range ?? package ?? packing ? type ? packing ? qty ?? aac242e \ d8a \ g \ lf ?? controller ?? current ? mode, ????????? offline ? thresholds ?? ext. ? industrial ?? 8 \ pin ? dip ?? tube ? 50 ? aac242a \ d8a \ g \ lf ?? controller ?? current ? mode, ????????? offline ? thresholds ?? automotive ?? 8 \ pin ? dip ?? tube ? 50 ? aac242e \ s8a \ g \ lf ?? controller ?? current ? mode, ????????? offline ? thresholds ?? ext. ? industrial ?? 8 \ pin ? soic ?? tube ? 98 ? aac242e \ s8a \ g \ lf \ tr ?? controller ?? current ? mode, ????????? offline ? thresholds ?? ext. ? industrial ?? 8 \ pin ? soic ?? 13 ? t&r ? (2) ?? 2500 ? aac242a \ s8a \ g \ lf ?? controller ?? current ? mode, ????????? offline ? thresholds ?? automotive ?? 8 \ pin ? soic ?? tube ? 98 ? aac242a \ s8a \ g \ lf \ tr ?? controller ?? current ? mode, ????????? offline ? thresholds ?? automotive ?? 8 \ pin ? soic ?? 13 ? t&r ? (2) ?? 2500 ? aac242e \ f8a \ g \ lf \ w ? controller ? current ? mode, ????????? offline ? thresholds ? ext. ? industrial ? 3mmx3mm ? 8 \ pin ? dfn ? waffle ? pack ? tbd ? ac242e \ f8a \ g \ lf \ tr ? controller ? current ? mode, ????????? offline ? thresholds ? ext. ? industrial ? 3mmx3mm ? 8 \ pin ? dfn ? t&r ? (2) ? tbd ? aac242a \ f8a \ g \ lf \ w ? controller ? current ? mode, ????????? offline ? thresholds ? automotive ? 3mmx3mm ? 8 \ pin ? dfn ? waffle ? pack ? tbd ? ac242a \ f8a \ g \ lf \ tr ? controller ? current ? mode, ????????? offline ? thresholds ? automotive ? 3mmx3mm ? 8 \ pin ? dfn ? t&r ? (2) ? tbd ? aac243e \ d8a \ g \ lf ?? controller ?? current ? mode, ???????? battery ? level ? thresholds ? ext. ? industrial ?? 8 \ pin ? dip ?? tube ? 50 ? aac243a \ d8a \ g \ lf ?? controller ?? current ? mode, ???????? battery ? level ? thresholds ? automotive ?? 8 \ pin ? dip ?? tube ? 50 ? aac243e \ s8a \ g \ lf ?? controller ?? current ? mode, ???????? battery ? level ? thresholds ? ext. ? industrial ?? 8 \ pin ? soic ?? tube ? 98 ? aac243e \ s8a \ g \ lf \ tr ?? controller ?? current ? mode, ???????? battery ? level ? thresholds ? ext. ? industrial ?? 8 \ pin ? soic ?? 13 ? t&r ? (2) ?? 2500 ? aac243a \ s8a \ g \ lf ?? controller ?? current ? mode, ???????? battery ? level ? thresholds ? automotive ?? 8 \ pin ? soic ?? tube ? 98 ? aac243a \ s8a \ g \ lf \ tr ?? controller ?? current ? mode, ???????? battery ? level ? thresholds ? automotive ?? 8 \ pin ? soic ?? 13 ? t&r ? (2) ?? 2500 ? ac243e \ f8a \ g \ lf \ w ? controller ? current ? mode, ???????? battery ? level ? thresholds ? ext. ? industrial ? 3mmx3mm ? 8 \ pin ? dfn ? waffle ? pack ? tbd ? aac243e \ f8a \ g \ lf \ tr ? controller ? current ? mode, ???????? battery ? level ? thresholds ? ext. ? industrial ? 3mmx3mm ? 8 \ pin ? dfn ? t&r ? (2) ? tbd ? ac243a \ f8a \ g \ lf \ w ? controller ? current ? mode, ???????? battery ? level ? thresholds ? automotive ? 3mmx3mm ? 8 \ pin ? dfn ? waffle ? pack ? tbd ? aac243a \ f8a \ g \ lf \ tr ? controller ? current ? mode, ???????? battery ? level ? thresholds ? automotive ? 3mmx3mm ? 8 \ pin ? dfn ? t&r ? (2) ? tbd ? (1) ? only ? rohs/lead \ free ? packaging ? is ? normally ? offered. ?? (2) ? t&r ?\? tape ? and ? reel ?? ordering information package dimensions and marking the aac242 and aac243 are available in a plastic 8-pin dip or soic package. refer to the latest version of specification aaps001 (asic advantages package numberi ng, marking, and outline standard, available at www.asicadvantage.com) for specific information concer ning the package dimensions and package marking. downloaded from: http:///
power management aac242/ 243 ? copyright 2010- asic advant age, inc. C aads00 012 / r127b - preliminary - oct ober 2010 8 / 8 the following is a brief overview of certai n terms and conditions of sale of produc t. for a full and complete copy of all the general terms and conditions of sale, visit our webpage http://www.asicadvantage.com/terms.htm. limited warranty the product is warranted that it will conform to the applic able specifications and be free of defects for one year. buyer is responsible for selection of, use of and resu lts obtained from use of the product. buyer indemnifies and holds asic advantage, inc. harmless for claims arising out of the application of asic advantage, inc.s products to buyers designs. applications described herein or in any catalogs, advertisements or other documents are for illustrative purposes only. critical applications products are not authorized for use in critical applications including aerospac e and life support applications. use of products in these applications is fully at the risk of the buyer. critical app lications include any system or device whose failure to perform can result in significant injury to the user. lethal voltages lethal voltages could be present in the applications. please comply with all applicable safety regulations. intellectual property rights and proprietary data asic advantage, inc. retains all intellectual property right s in the products. sale of products does not confer on buyer any license to the intellectual property. asic advant age, inc. reserves the right to make changes without notice to the products at any time. buyer agrees not to us e or disclose asic advantage inc.s proprietary information without written consent. trademarks and patents - in-plug ? is a registered trademark of asic advantage, inc. - aais modified snubber network is patented under the us patent # 6,233,165 protection for custom solutions when aai accepts to design and manufacture products to bu yers designs or specifications, buyer has certain obligations to provide defense in a suit or proceeding clai ming infringement of a patent, copyright or trademark or for misappropriation of use of any trade secrets or for unfair competition. compliance with laws buyer agrees that at all times it will comply with all applicable federal, state, municipal, and local laws, orders and regulations. buyer agrees to comply with all applicable re strictions on exports and re-e xports including obtaining any required u.s. government license, author ization, or approval. buyer shall pay any duties, levies, taxes, brokerage fees, or customs fees imposed on the products. title and delivery all shipments of goods shall be delivered exworks, sunnyvale, ca, u.s.a. title in the goods shall not pass to buyer until asic advantage, inc. has received in full all amounts owed by buyer. latest datasheet updates for the latest datasheet updates, visit our web page: http://www.asicadvantage.com. worldwide representatives to access aais list of worldwide representativ es, visit our web page http://www.asicadvantage.com. copyrights copyrights and all other proprietary right s in the content rests with asic adv antage inc. (aai) or its licensors. all rights in the content not expressly gr anted herein are reserved. except as ot herwise provided, the content published on this document may be reproduced or distributed in unm odified form for personal non-commercial use only. any other use of the content, including without limitation distribution, reproduction, modification, display or transmission without the prior written consent of aai is strictly prohibited. all copyright and other proprietary notices shall be retained on all reproductions. asic advantage inc . 1290-b reamwood ave, sunnyvale california 94089, usa tel: (1) 408-541-8686 fax: (1) 408-541-8675 websites: http://www.asicadvantage.com downloaded from: http:///
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