general description the MAX1999 evaluation kit (ev kit) demonstrates the MAX1999? standard application circuit. this dc-dc con- verter steps down high-voltage batteries and/or ac adapters, generating system supplies for notebook com- puters. the MAX1999 ev kit provides dual 5v and 3.3v output voltages from a 7v to 24v battery input range. it delivers up to 5a output current for the 5v output and 5a for the 3.3v output with greater than 90% efficiency. the ev kit operates at 200khz/300khz switching frequency (5v/3.3v, respectively) and has superior line-and-load- transient response. this ev kit is a fully assembled and tested circuit board. it allows the evaluation of other output voltages in the 2v to 5.5v range by changing feedback resistors r1?4. this ev kit can also be used to evaluate the max1777 (200khz/5.0v smps and 300khz/3.3v smps) and the max1977 (400khz/5.0v smps and 500khz/3.3v smps). features 7v to 24v input voltage range 3.3v and 5v output voltages 2v to 5.5v adjustable outputs (external resistors) 5a output current (3.3v output) 5a output current (5v output) no current-sense resistor needed (MAX1999) accurate current sense with current-sense resistor (max1777/max1977) 200khz/300khz switching frequency (5v/3.3v, respectively) power-good (pgood) output fault protection enable/disable 28-pin qsop package low-profile components fully assembled and tested evaluates: max1777/max1977/MAX1999 MAX1999 evaluation kit ________________________________________________________________ maxim integrated products 1 ordering information 19-2499; rev 0; 7/02 for pricing, delivery, and ordering information, please contact maxim/dallas direct! at 1-888-629-4642, or visit maxim? website at www.maxim-ic.com. part temp range ic package MAX1999evkit 0 o c to +70 o c 28 qsop note: to evaluate the max1777/max1977, request a max1777eei/max1977eei free sample with the MAX1999evkit. designation qty description c1, c2, c3 3 10f, 25v ceramic capacitors (1812) taiyo yuden tmk432bj106km or tdk c4532x5r1e106m c4 0 not installed (1812) c5, c7 0 not installed, d case c6 1 470f, 4v, 40m ? , low-esr capacitor, d case sanyo 4tpb470m c8 1 330f, 6.3v, 40m ? , low-esr capacitor, d case sanyo 6tpb330m c9, c10, c12, c15 4 0.1f ceramic capacitors (0805) c11, c24 2 1f, 10v x5r ceramic capacitors (0805) taiyo yuden lmk212bj105kg or tdk c2012x5r105m designation qty description c13, c14 0 not installed c16 1 0.22f, 16v x5r ceramic capacitor (0805) taiyo yuden emk212bj224kg c17 1 4.7f, 35v tantalum capacitor, c case sprague 595d475x0035c2b c18, c19 2 4.7f, 16v tantalum capacitors, a case sprague 595d475x0016a2b d1 1 100ma, 30v dual schottky diode central semiconductor cmpsh-3a d2, d3 2 1a, 30v schottky diodes nihon ep10qy03 toshiba crs02 ju1, ju2 2 3-pin headers ju3, ju5 2 4-pin headers component list
evaluates: max1777/max1977/MAX1999 recommended equipment 7v to 24v power supply, battery, or notebook ac adapter dummy loads capable of sinking 5a digital multimeters (dmms) 100mhz dual-trace oscilloscope quick start 1) ensure that the circuit is connected correctly to the supplies and dummy load before applying any power. 2) verify that the shunts are across ju1 pins 1 and 2, ju2 pins 1 and 2, ju3 pins 1 and 4, and ju5 pins 1 and 4. 3) turn on the power supply. 4) verify that the output voltages are 3.3v and 5v. evaluating other output voltages the ev kit outputs are preset to 3.3v and 5v. however, the output voltages can also be adjusted between 2v and 5.5v by selecting r1/r2 and r3/r4 values. select feedback resistors r2 and r4. r1 and r3 are then given by: r1 (or r3) = r2 (or r4) x [(v out /v fb ) - 1] where v fb = 2v. MAX1999 evaluation kit 2 _______________________________________________________________________________________ component list (continued) designation qty description l1 1 7.6h, 5.9a power inductor sumida cdrh127-7r6 l2 1 4.7h, 5.7a power inductor sumida cdrh124-4r7 n1, n3 2 n-channel mosfet, 8-pin so international rectifier irf7807v or fairchild fds6612a n2, n4 2 n-channel mosfet, 8-pin so international rectifier irf7811av or fairchild fds6670a r1, r3, r10 r14 0 not installed (0805) r2, r4 0 not installed, short pc trace (0805) r5 1 3.9 ? 5% resistor (1206) designation qty description r6 1 100k ? 5% resistor (0805) r7, r9 2 1m ? 5% resistors (0805) r8, r18 2 10 ? 5% resistors (0805) r15, r16 0 not installed, short pc trace (2010) r17 1 47 ? 5% resistor (0805) u1 1 MAX1999eei, 28-pin qsop none 4 shunts (ju1, ju2, ju3, ju5) none 4 rubber feet none 1 MAX1999 pc board none 1 MAX1999 data sheet none 1 MAX1999 ev kit data sheet component suppliers supplier phone fax website central semiconductor 516-435-1110 516-435-1824 www.centralsemi.com fairchild 408-721-2181 408-721-1635 www.fairchildsemi.com international rectifier 310-322-3331 310-322-3332 www.irf.com nihon 847-843-7500 847-843-2798 www.niec.co.jp sanyo 619-661-6835 619-661-1055 www.sumida.com sprague/vishay 270-324-4140 270-490-7222 www.vishay.com sumida 708-956-0666 708-956-0702 www.sumida.com taiyo yuden 408-573-4150 408-573-4159 www.t-yuden.com tdk 847-390-4373 847-390-4428 www.component.tdk.com note: please indicate that you are using the MAX1999 when contacting these component suppliers.
evaluating the max1777/max1977 this ev kit also can be used to evaluate the max1777/ max1977. the max1777 operates at 200khz/300khz switching frequency and the max1977 operates at 400khz/500khz switching frequency (5v/3.3v). the max1777 and the max1977 use accurate current- sense resistors, r15 and r16: 1) remove the MAX1999 and install a max1777 or max1977. 2) cut open the traces shorting sense resistors r15 and r16. 3) install sense resistors r15 and r16. 4) short resistor r10 (leave ju6 open). evaluates: max1777/max1977/MAX1999 MAX1999 evaluation kit ________________________________________________________________________________________ 3 ref 2v ld03 3.3v ld03 n.c. (cs3) out3 lx3 bst3 dh3 v cc vcc bst5 v+ ilim3 lim5 ldo5 lx5 dh5 bst5 ton (cs5) dl5 on5 on3 out5 fb5 ref u1 MAX1999 (max1777) (max1977) r5 3.9? r8 10? 8 bst5 20 5 11 18 13 19 14 16 17 21 3d1 28 r l 24 27 15 22 fb3 7 1 25 8 26 dl3 10 23 2 12 6 3 9 21 4 1 2 3 v+ ju1 4 1 2 3 vcc ju3 4 1 2 3 vcc ju5 l2 4.7h c11 1f 10v c18 4.7f 16v ju7 ju8 r14 open r12 open r11 open r17 47? r18 10? r6 100k? r9 1m? r13 open ref vcc vcc ju6 ju4 5v on/off shdn shdn pro skip n4 7 8 d2 6 5 2 1 4 3 n3 7 8 6 5 2 1 4 3 c3 10f 25v c4 open l1 7.6h 7 8 6 5 n1 7 8 6 5 2 1 4 3 n2 2 1 4 3 c2 10f 25v c1 10f 25v ld05 +5v c14* open c10 0.1f c24 1f 10v 3.3v on/off 1 2 3 vcc ju2 pgood pgood gnd vcc gnd vin 7v to 24v v+ c17 4.7f 35v c15 0.1f r10 open c13* open r7 1m? c9 0.1f d3 vout2 +5v, 5a c12 0.1f c16 0.22f c19 4.7f 16v c8 330f 6.3v c7 open r3 open ref ref r4 short (pc trace) r16 short (pc trace) vout1 3.3v, 5a c6 470f 4v c5 open r2 short (pc trace) r1 open r15 short (pc trace) vcc vcc *optional c13 and c14 required for ultrasonic mode operation (MAX1999 only). see table 2. figure 1. MAX1999 ev kit schematic
evaluates: max1777/max1977/MAX1999 MAX1999 evaluation kit 4 _______________________________________________________________________________________ table 1. jumper ju1 functions ( shdn mode selection) ju1 shdn pin MAX1999 output 1 and 2 connected to v+ MAX1999 enabled; ref, ldo3, and ldo5 active; v out1 (3.3v) depends on ju3; v out2 (5.0v) depends on ju5 2 and 3 connected to gnd shutdown mode; ref, ldo3, and ldo5 off; v out1 = 0v and v out2 = 0v not installed connected to shdn pad MAX1999 can be driven by an external signal table 2. jumper ju2 functions (skip mode selection) ju2 skip pin operating mode 1 and 2 connected to vcc low-noise mode, forced fixed-frequency pwm operation. 2 and 3 connected to gnd n or m al op er ati on, al l ow s autom ati c p wm /p fm sw i tchover for p ul se- ski p p i ng at l i g ht l oad , r esul ti ng i n hi g hest effi ci ency. not installed floating ultrasonic pulse-skipping mode (20khz min). install c13, c14 (470pf) for MAX1999 ultrasonic mode operation to ensure proper negative ultrasonic current sensing (v neg(s) ). table 3. jumper ju3 functions (output voltage v out1 control) ju3 on3 pin output voltage (v out1 ) 1 and 2 connected to gnd v out1 = 0v, disabled 1 and 3 connected to ref (on5 = vcc) v out1 (3.3v) starts after v out2 (5v) reaches regulation 1 and 4 connected to vcc v out1 = 3.3v, enabled table 4. jumper ju4 functions (protection selection) ju4 pro pin protection installed connected to vcc undervoltage and overvoltage fault protection are disabled. not installed connected to gnd through resistor r9 undervoltage and overvoltage fault protection are enabled. refer to the fault protection section in the MAX1999 data sheet for more information. jumper settings
evaluates: max1777/max1977/MAX1999 MAX1999 evaluation kit _______________________________________________________________________________________ 5 table 5. jumper ju5 functions (output voltage v out2 control) ju5 on5 pin output voltage (v out2 ) 1 and 2 connected to gnd v out2 = 0v, disabled 1 and 3 connected to ref (on3 = vcc) v out2 (5v) starts after v out1 (3.3v) reaches regulation 1 and 4 connected to vcc v out2 = 5v, enabled table 6. jumper ju6 functions (switching-frequency selection) ju6 ton pin frequency (khz) not installed connected to vcc through resistor r7 200/300 (as shipped) installed connected to gnd 400/500 table 7. jumper ju7 functions (fixed/adjustable current-limit selection for v out2 ) ju7 ilim5 pin current-limit threshold (mv) short connected to vcc through a pc board trace. 100 (default) open connected to ref through resistor-divider r13/r14. refer to the current-limit circuit section in the MAX1999 data sheet for information on selecting r13/r14. adjustable from 50 to 200 table 8. jumper ju8 functions (fixed/adjustable current-limit selection for v out1 ) ju8 ilim3 pin current-limit threshold (mv) short connected to vcc through a pc board trace. 100 (default) open connected to ref through resistor-divider r11/r12. refer to the current-limit circuit section in the MAX1999 data sheet for information on selecting r11/r12. adjustable from 50 to 200 jumper settings (continued) important: do not change the operating frequency without first recalculating component values. the switching frequency has a sig- nificant effect on the peak current-limit level, mosfet heating, preferred inductor value, pfm/pwm switchover point, output noi se, efficiency, and other critical parameters.
evaluates: max1777/max1977/MAX1999 MAX1999 evaluation kit 6 _______________________________________________________________________________________ figure 2. MAX1999 ev kit component placement guide top silkscreen figure 3. MAX1999 ev kit pc board layout?omponent side
evaluates: max1777/max1977/MAX1999 MAX1999 evaluation kit _______________________________________________________________________________________ 7 figure 4. MAX1999 ev kit pc board layout?round layer 2 figure 5. MAX1999 ev kit pc board layout?round layer 3
evaluates: max1777/max1977/MAX1999 MAX1999 evaluation kit maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim product. no circu it patent licenses are implied. maxim reserves the right to change the circuitry and specifications without notice at any time. 8 _____________________maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 ? 2002 maxim integrated products printed usa is a registered trademark of maxim integrated products. figure 6. MAX1999 ev kit pc board layout?older side figure 7. MAX1999 ev kit component placement guide bottom silkscreen
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