1 description ltc 4233/ ltc 4234 10a/20a guaranteed soa hot swap controller demonstration circuit 2116 a features the LTC4233/ lt c ? 4234 10a /20 a guaranteed soa hot swap ? controllers. the LTC4233 and ltc4234 are ideally suited for compact power distribution control in 2.9 v to 15 v applications for hot board insertion protection, high side power switching, and electronic circuit breaker functions. they provide a rich set of features to support hot swap applications including: ? 2.5% accurate under voltage and overvoltage protection ? overtemperature protection ? adjustable inrush current control ? adjustable, 11% accurate current limit ? adjustable output v oltage ramp rate l , lt, ltc, ltm, linear technology and the linear logo are registered trademarks and hot swap is a trademark of linear technology corporation. all other trademarks are the property of their respective owners. p erformance s ummary ? configurable for auto retry or latch off for overcurrent faults ? power good and fault outputs available in 38-pin 5mm 9 mm qfn packages, the ltc4234 is showcased on dc2116 a-a while the LTC4233 is showcased on dc2116 a-b , both configured for a 12v application. by changing a few passive components , 2.9v to 15v applications can easily be evaluated. design files for this circuit board are available at http://www .linear.com/demo/dc2116a specifications are at t a = 25c parameter conditions value input supply voltage range 2.9v to 15v nominal operating voltage 12.0v overvoltage lockout nominal 15.2v undervoltage lockout (voltage falling) nominal 9.2v undervoltage lockout (voltage rising) nominal 9.9v output current limit nominal (LTC4233) 11.2a nominal (ltc4234) 22.5a maximum load capacitance nominal 8200f timer expiration period nominal 1.2ms or 2.0ms dc2116afa demo manual dc2116a
2 quick s tart p roce d ure table 1. power input and output connections nomenclature connector description vdd e13 12v in gnd e14 12v in return vout e6 12v out gnd e7 12v out return table 3. led indicators nomenclature part designator description fault d1 (red) indicates overcurrent fault power bad d2 (red) v out not up to full voltage input power d3 (green) input voltage present output power d4 (green) output voltage present table 4. jumpers nomenclature part designator description autoretry jp1 on position for autoretry timer duration jp2 1.2ms or 2.0ms timer duration table 2. test points nomenclature turret description intvcc e1 intv cc monitor timer e2 timer pin monitor pg e3 pg pin monitor iset e4 i set pin monitor imon e5 i mon pin monitor gnd e8 v out return monitor vout e9 v out monitor uv e10 uv pin monitor ov e11 ov pin monitor vdd e12 v dd monitor gnd e15 v dd return monitor sense e16 sense pin monitor f lt e17 f lt pin monitor gate e18 gate pin monitor gnd e19, e20, e21 ground dc2116afa demo manual dc2116a
3 d c 2116 a - a quick s tart p roce d ure dc2116a-a is easy to set up to evaluate the performance of the ltc4234. refer to figure 1 for proper measurement equipment setup and follow the procedure below. dc2116a has two user configurable jumper options: ? jp1 autoretry C set to on for auto retry or off for latch off on over-current faults . ( default position: off) ? jp2 timer duration C set to 2 ms for the internal 2ms timer or 1.2 ms determined by c2, c2 may be replaced for other timer durations. (default position: 1.2ms) leds indicate the state of input power ( d2), output power (d4), fault ( d3) and pg ( d1). load current can be moni - tored on the imon turret, which has a value of 0.1v/a determined by rmon (20k.) set an adjustable power supply, capable of supplying 30 amps, at 16 v. turn off power and connect the supply to the vdd and gnd banana jacks. connect a suitable load to the vout and gnd banana jacks. this load can be an electronic load or power resis - tors capable of dissipating 300w. note: because the ltc4234 incorporates foldback current limiting, the nominal startup current supplied to the load is approximately 5.7 a, and may be as low as 4 a. this cur- rent limit increases linearly until the fb pin exceeds 0.6v (v out > 5.1 v). an electronic constant current load set to 20 amps will not permit the circuit to turn on unless it is gated on by the pg signal ( as would be the case with a dc/dc converter controlled by the pg signal). resistive loading will not have this problem. figure 1. proper measurement equipment setup + ? adjustable power supply test loads dc2116 f01 + ? + ? dc2116afa demo manual dc2116a
4 d c2116 a-a quick s tart p roce d ure d c 2116 a -b quick s tart p roce d ure turn on the power supply; verify the input voltage is 12v. verify the output voltage and the load current; d3 and d4 should both be illuminated ( input voltage and output volt - age, respectively) and both d 1 ( f lt ) and d 2 ( pg) should be off. on power-up, observe the slope of v out . this should be in the range of 0.15 to 0.55 v/ms, corresponding to a ramp-up time of 22 ms to 80 ms to 12 v. with the circuit functioning, additional evaluations can now be performed. ov/uv/pg thresholds C set the input supply to zero and ramp the voltage slowly, observing the following events. above 10.0 v, the circuit will be out of uv lockout and the output should ramp up, lighting d4. above 10.9 v the fb pin will be past its threshold, asserting the pg pin high and extinguishing d2. increasing the supply past 15.2 v will engage ov lockout; d4 will extinguish and d2 will light. note that the voltages indicated in this step are maximums, taking into consideration the tolerances of the resistors and the ltc4234 thresholds. current limit thresholds C with the input supply set to 12v , load the output with a 0.59 power resistor capable of dissipating 300 w. power should remain on, as the current will be below the 20 a minimum current limit threshold. next, load the output with a 0.48 power resistor. power should be interrupted, as the current will be above the 25 a maximum current limit threshold. inrush into capacitive load C one of the main functions of a hot swap circuit is to provide controlled ramp-up into a capacitive load to avoid disturbing the input power sup - ply. for the following tests, ensure that the autoretry jumper is set to off and the timer duration jumper is set to 2.0ms. to guarantee that current limit is never reached during ramp-up into a capacitor, the current must be less than the minimum current limit threshold of 4 a when the gate ramp rate is at its maximum value of 0.6v/ ms . ( note that the minimum current limit threshold occurs when the fb pin is at 0v.) c = i/(dv/dt) = 4a/(0.6v/ms) = 6667f thus the circuit will always power up successfully with a 6000f capacitor at v out , and observation of the timer turret post will show that it never begins to ramp. the LTC4233, on the dc 2116a-b, should be tested as above with actual values scaled to values shown in the data sheet. dc2116afa demo manual dc2116a
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. s chematic diagram 5 5 4 4 3 3 2 2 1 1 d d c c b b a a 05/21/2013 10/20 amp integrated hot swap controller demo circuit 2116a 05/21/2013 LTC4233/ltc4234 vdd gnd gnd vout vout gnd vdd gnd sense uv ov flt timer intvcc pg iset imon note: 1. all resistors are 0603 package, 1% u.o.n. autoretry off on timer duration 2 ms gate gnd gnd gnd banana banana banana banana 1.2 ms * assembly options -b LTC4233 ass'y u1 ltc4234 -a current 20a 10a input p0wer fault output p0wer power bad * vdd vout revision history description date approved eco rev robert smith production 1 - revision history description date approved eco rev robert smith production 1 - revision history description date approved eco rev robert smith production 1 - size date: .ver .on ci sheet of title: approvals pcb des. app eng. technology fax: (408)434-0507 milpitas, ca 95035 phone: (408)432-1900 1630 mccarthy blvd. ltc confidential-for customer use only customer notice linear technology has made a best effort to design a circuit that meets customer-supplied specifications; however, it remains the customer's responsibility to verify proper and reliable operation in the actual application. component substitution and printed circuit board layout may significantly affect circuit performance or reliability. contact linear technology applications engineering for assistance. this circuit is proprietary to linear technology and schematic supplied for use with linear technology parts. scale = none www.linear.com 1 1 1 n/a m.hawkins r. smith size date: .ver .on ci sheet of title: approvals pcb des. app eng. technology fax: (408)434-0507 milpitas, ca 95035 phone: (408)432-1900 1630 mccarthy blvd. ltc confidential-for customer use only customer notice linear technology has made a best effort to design a circuit that meets customer-supplied specifications; however, it remains the customer's responsibility to verify proper and reliable operation in the actual application. component substitution and printed circuit board layout may significantly affect circuit performance or reliability. contact linear technology applications engineering for assistance. this circuit is proprietary to linear technology and schematic supplied for use with linear technology parts. scale = none www.linear.com 1 1 1 n/a m.hawkins r. smith size date: .ver .on ci sheet of title: approvals pcb des. app eng. technology fax: (408)434-0507 milpitas, ca 95035 phone: (408)432-1900 1630 mccarthy blvd. ltc confidential-for customer use only customer notice linear technology has made a best effort to design a circuit that meets customer-supplied specifications; however, it remains the customer's responsibility to verify proper and reliable operation in the actual application. component substitution and printed circuit board layout may significantly affect circuit performance or reliability. contact linear technology applications engineering for assistance. this circuit is proprietary to linear technology and schematic supplied for use with linear technology parts. scale = none www.linear.com 1 1 1 n/a m.hawkins r. smith r3 20k cgate opt + cout1 22uf 25v c1 1.0uf 16v + cin opt e2 rset opt 0805 e10 r4 10k 5% 0805 e11 u1 out 9 out 10 out 11 out 12 out 13 out 14 out 15 out 16 out 17 out 18 out 19 out 20 out 21 out 22 out 23 out 24 out 25 out 26 out 27 out 28 out 29 out 30 fb 37 gate 32 pg 35 i set 38 i mon 3 gnd 7 sense 40 sense 8 vdd 6 vdd 33 vdd 39 intvcc 5 timer 4 flt 36 uv 1 ov 2 sense- 34 sense 31 e15 rgate opt e14 e3 e13 d2 red 2 1 e5 jp1 1 3 2 r1 10k 5% 0805 e6 e1 d1 red 2 1 e7 e16 r8 226k r5 10k 5% 0805 c2 0.1uf 16v r2 150k + cout2 opt r10 20k e21 d4 green 2 1 r6 10k 5% 0805 d5 smaj22a 2 1 rmon 20k 0805 e9 e20 jp2 1 3 2 r9 20k e4 e8 e17 e12 e18 d3 green 2 1 e19 r7 140k dc2116afa demo manual dc2116a
6 linear technology corporation 1630 mccarthy blvd., milpitas, ca 95035-7417 (408) 432-1900 fax : (408) 434-0507 www.linear.com linear technology corporation 2015 lt 0815 rev a ? printed in usa demonstration board important notice linear technology corporation ( lt c ) 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 lt c 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 p arty 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 lt c 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 whatsoever. lt c assumes no liability for applications assistance, customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind. lt c 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 lt c applica- tion engineer. mailing address: linear technology 1630 mccarthy blvd. milpitas, ca 95035 copyright ? 2004, linear technology corporation dc2116afa demo manual dc2116a
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