1 description LT8364 low i q boost/sepic/inverting regulator demo circuit 2716a features the LT8364 in boost con - figuration. it is designed to convert a 4.5v to 20v source to 24v, with up to 1.6a, depending on input voltage, with a switching frequency of 2mhz . the LT8364 can operate with inputs as high as 60v , however, in this demo circuit, the input is limited by the level of the output voltage. refer to figure 4 for load current versus input voltage. the demo board contains a selectable jumper, jp1, to aid in the selection of the desired sync pin mode of operation. the default setting is burst mode ? operation. this layout is optimized for good emi performance and solution size. input and output filters and an optimized l , lt, ltc, ltm, linear technology, the linear logo and burst mode are registered trademarks of analog devices, inc. all other trademarks are the property of their respective owners. performance summary hot?loop, comprised of c11 and c12 are necessary to pass cispr 25 class 5 emissions, and are added by default. these components can be excluded in applications not requiring noise immunity. radiated emissions plots are included in this manual. the data sheet gives a complete description of the device, operation and application information. the data sheet must be read in conjunction with this demo manual. design files for this circuit board are available at http: //www.linear.com/demo/dc2716a specifications are at t a = 25c symbol parameter conditions min typ max units v in input supply range 4.5 20 v v out output voltage range v in = 12v, i load = 1.2a 23.25 24 24.75 v ripple v in = 12v, i load = 1.2a 50 mv efficiency v in = 12v, i load = 1a 93 % f sw 2 mhz dc2716af demo manual dc2716a
2 quick start procedure figure 2. measure output ripple figure?1. dc2716a proper equipment setup demo circuit 2716a is easy to set up to evaluate the performance of the LT8364 . refer to figure 1 for proper measurement equipment setup and follow the proce - dure?below: note: when measuring the input or output voltage ripple, care must be taken to avoid a long ground lead on the oscilloscope probe. measure the input or output voltage ripple by touching the probe tip directly across the v in or v out and gnd terminals. see figure 2 for proper scope probe technique. 1. with power off, connect the input power supply to v in and gnd. 2. turn on the power at the input. note. make sure that the input voltage does not exceed?20v. 3. check for the proper output voltage. if there is no output, temporarily disconnect the load to make sure that the load is not set too high. note: 4. once the proper output voltage is established, adjust the load within the operating range and observe the output voltage regulation, ripple voltage, efficiency and other parameters. vin gnd dc2716af demo manual dc2716a
3 figure?4. guaranteed load current versus input voltage figure?3. efficiency versus load current quick start procedure typical performance characteristics figure?5. cispr 25 radiated emission test peak detection, vertical polarization) v in = 12v figure?6. cispr 25 radiated emission test (average detection, vertical polarization) v in = 12v dc2716af demo manual dc2716a v in (v) 0.5 100 efficiency (%) dc2716a v in = 20v v in = 12v v in = 5v 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 4 1.5 1.6 1.7 1.8 guaranteed load current (a) dc2716a f04 v out = 24v, i out = 1a, 2mhz switching frequency frequency (mhz) 30 130 6 230 330 430 530 630 730 830 930 1030 ?15 8 ?10 ?5 0 5 10 15 20 25 30 35 10 40 45 50 amplitude (dbv/m) dc2716a f05 class 5 peak limit spread spectrum mode v out = 24v, i out = 1a, 2mhz switching frequency frequency (mhz) 30 12 130 230 330 430 530 630 730 830 930 1030 14 ?15 ?10 ?5 0 5 10 15 20 25 30 16 35 40 45 50 amplitude (dbv/m) dc2716a f06 class 5 peak limit spread spectrum mode load current (ma) 0.1 0.4 1 10 100 1k 10k 50 60 70 80 90
4 parts list item qty reference part description manufacturer/part number required circuit components 1 1 c1 cap., 4.7f, x7r, 25v, 10%, 1206 murata, gr m31cr71e475ka88l 2 1 c2 cap., 33f , alum. elect., 50v, 20% sun electronic industries corp., 50 ce33pcs 3 1 c3 cap., 10f, x7r, 25v, 10%, 1206 murata, gr m31cr71e106ka12l 4 1 c4 cap., 10f, x7s, 50v, 10%, 1210 murata, gc m32ec71h106ka03l 5 1 c6 cap., 0.22f, x7r, 25v, 10%, 0603 murata, gr m188r71e224ka88d 6 1 c7 cap., 1f, x5r, 25v, 10%, 0603 murata, gr m188r61e105ka12d 7 1 c9 cap., 2200pf, x7r, 25v, 10%, 0603 murata, gr m188r71e222ka01d 8 1 c10 cap., 1f, x5r, 50v, 10%, 0603 murata, gr m188r61h105kaald 9 4 c11, c12, c13, c14 cap., 0.1f, x7r, 50v, 10%, 0402, aec-q200 murata, gc m155r71h104ke02d 10 1 d1 diode, schottky, 60v, 2.0a, powerdi 123 diodes inc., dfls260-7 11 1 fb1 ind., 600?, ferrite bead, 25%, 2a, 0805 wurth elektronik, 742792040 12 1 l1 ind., 2.2h, 3.25a, 61m?, smd wurth electronics inc., 74437324022 13 1 l2 ind., 470nh, 3.6a, 31m?, smd wurth elektronik, 74479299147 14 2 r1, r4 res., 1m?, 1%, 1/10w, 0603 vishay, crcw06031 m00fkea 15 1 r3 res., 732k, 1%, 1/10w, 0603 vishay, crcw0603732kfkea 16 1 r5 res., 100k, 1%, 1/10w, 0603 vishay, crcw0603100kfkea 17 1 r6 res., 71.5k, 1%, 1/10w, 0603 vishay, crcw060371 k5fkea 18 1 r7 res., 22k, 1%, 1/10w, 0603 vishay, crcw060322 k0fkea 19 1 r8 res., 20k, 1%, 1/10w, 0603 vishay, crcw060320 k0fkea 20 1 u1 ic, boost/sepic/inverting converter linear tech., LT8364ede additional demo board circuit components 1 1 r2 res., 0?, 1/10w, 0603 vishay, crcw06030000z0ea 2 1 c5 (opt) cap., opt, 0603 3 0 c8 cap., option, 0603 hardware: for demo board only 1 7 e1, e2, e3, e4, e5, e6, e7 test point, turret, 0.094", mtg. hole mill-max, 2501-2-00-80-00-00-07-0 2 1 jp1 conn., header, male, 2 5.2mm , st, tht wurth elektronik, 62001021121 3 1 xjp1 conn., shunt, female, 2 pos, 2mm wurth elektronik, 60800213421 4 4 mp1, mp2, mp3, mp4 standoff, nylon, 0.50" keystone, 8833 dc2716af demo manual dc2716a
5 information furnished by linear technology corporation is believed to be accurate and reliable. however, no responsibility is assumed for its use. linear technology corporation makes no representa - tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. schematic diagram all capacitors are 0603. notes: unless otherwise specified 1. all resistors are 0603. see demo manual for load current * * burst / ssfm burst pulse skipping pulse skipping / ssfm sync 2mhz vout intvcc vout l1 2.2uh 74437324022 e7 vout 24v c11 0.1uf 0402 50v + c2 33uf 50ce33pcs 50v u1 LT8364ede en/uvlo 2 sync 10 ss 9 bias 5 vin 3 fbx 7 intvcc 4 sw1 11 gnd 13 rt 8 vc 6 sw2 12 nc 1 e4 sync tp1 1 c14 0.1uf 0402 50v c12 0.1uf 0402 50v r2 0 r7 22k 1% r8 20k 1% c10 1uf 50v e1 vin 4.5v 20v e5 gnd c7 1uf c1 4.7uf 1206 25v c3 10uf 1206 25v l2 470nh 74479299147 r5 100k c6 0.22uf d1 dfls260 7 2 1 c8 opt r4 1m r1 1m jp1 1 3 5 6 4 2 7 8 9 10 e3 en/uvlo c13 0.1uf 0402 50v c5 opt r3 732k fb1 742792040 e6 gnd c9 2200pf e2 gnd c4 10uf 1210 50v r6 71.5k intvcc dc2716af demo manual dc2716a
6 ? linear technology corporation 2017 lt 1017 ? printed in usa demonstration board important notice linear technology corporation (ltc) provides the enclosed product(s) under the following as is conditions: this demonstration board (demo board) kit being sold or provided by linear technology is intended for use for engineering development or evaluation purposes only and is not provided by ltc for commercial use. as such, the demo board herein may not be complete in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety measures typically found in finished commercial goods. as a prototype, this product does not fall within the scope of the european union directive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations. if this evaluation kit does not meet the specifications recited in the demo board manual the kit may be returned within 30 days from the date of delivery for a full refund. the foregoing warranty is the exclusive warranty made by the seller to buyer and is in lieu of all other warranties, expressed, implied, or statutory, including any warranty of merchantability or fitness for any particular purpose. except to the extent of this indemnity, neither party shall be liable to the other for any indirect, special, incidental, or consequential damages. the user assumes all responsibility and liability for proper and safe handling of the goods. further, the user releases ltc from all claims arising from the handling or use of the goods. due to the open construction of the product, it is the users responsibility to take any and all appropriate precautions with regard to electrostatic discharge. also be aware that the products herein may not be regulatory compliant or agency certified (fcc, ul, ce, etc.). no license is granted under any patent right or other intellectual property whatsoeve r . ltc assumes no liability for applications assistance, customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind. ltc currently services a variety of customers for products around the world, and therefore this transaction is not exclusive. please read the demo board manual prior to handling the product. persons handling this product must have electronics training and observe good laboratory practice standards. common sense is encouraged. this notice contains important safety information about temperatures and voltages. for further safety concerns, please contact a ltc application engineer. mailing address: linear technology 1630 mccarthy blvd. milpitas, ca 95035 copyright ? 2004, linear technology corporation dc2716af demo manual dc2716a
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