general description the max1960 evaluation kit (ev kit) is a fully assembled and tested surface-mount circuit board that evaluates the max1960 family of pwm synchronous step-down controllers. there are two circuits on the board. the first has the max1960 installed but can also be used to evaluate the max1961. this circuit provides a 1.8v out- put at up to 15a, or the output can be adjusted from 0.8v to (0.9 ? v in ). the second circuit evaluates the max1962. components for the second circuit are not installed on the standard evaluation kit. both circuits can operate with a 2.35v to 5.5v input voltage. features 2.35v to 5.5v input supply range 1.8v output at up to 15a output voltage adjustable down to 0.8v fixed-frequency pwm operation selectable 500khz/1mhz or external synchronization 4% voltage margining evaluates: max1960/max1961/max1962 max1960 evaluation kit ________________________________________________________________ maxim integrated products 1 designation qty description c1 1 0.47? ?0%, 10v x5r ceramic capacitor (0603) tdk c1608x5r1a474k or equivalent c2, c3, c13 0 not installed; 0.47? ?0%, 10v x5r ceramic capacitors (0603) tdk c1608x5r1a474k or equivalent (tripler) c4 1 1? ?0%, 6.3v x5r ceramic capacitor (0402) panasonic ecj0eb0j105m or equivalent c5 1 0.1? ?0%, 10v x5r ceramic capacitor (0402) tdk c1005x5r1a104k or equivalent c6 1 2.2? ?0%, 6.3v x5r ceramic capacitor (0603) tdk c1608x5r0j225k or equivalent c7, c8, c9 3 10? ?0%, 6.3v x5r ceramic capacitors (0805) panasonic ecj2fb0j106m or equivalent c10, c38 2 0.22? ?0%, 6.3v x5r ceramic capacitors (0402) tdk c1005x5r0j224k or equivalent c11 1 not installed, 10pf ceramic capacitor (0402) c12 1 0.01? ?0%, 25v x7r ceramic capacitor (0402) murata grp155r71e103k or equivalent component list ordering information 19-2976; rev 0; 9/03 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 MAX1960EVKIT 0 c to +70 c 20 qsop designation qty description c14, c15 2 680f, 2.5v, 8m ? poscaps sanyo 2r5tpd680m8 c16, c17 2 4700pf 10%, 50v x7r ceramic capacitors (0603) tdk c1608x7r1h472k or equivalent c37 1 470f, 6.3v poscap sanyo 6tpb470m d1 1 single schottky diode (sot-323) central cmssh-3 d2 d5 0 not installed, schottky diodes (sod-123) central cmhsh5-2l (tripler) ju1, ju2, ju3 3 3-pin headers ju4 1 4-pin 3-way header l1 1 0.22h inductor sumida cdep105(s)-0r2nc-50 n1 1 n-channel mosfet (d-pak) irf irlr7821 n2 1 n-channel mosfet (d-pak) irf irlr7833 r1 1 301k ? 1% resistor (0603) r2 1 6.8k ? 5% resistor (0603) r3 1 12.4k ? 1% resistor (0603) r4 1 10k ? 1% resistor (0603) r5 1 10 ? 5% resistor (0603) r12, r13 2 1 ? 5% resistors (0603) u1 1 maxim max1960eep (20-pin qsop) none 4 shunts, two position none 1 MAX1960EVKIT pc board
evaluates: max1960/max1961/max1962 max1960 evaluation kit 2 _______________________________________________________________________________________ designation qty description c18, c19 2 680f, 2.5v, 8m ? poscaps sanyo 2r5tpd680m8 or equivalent c20, c21 2 4700pf 10%, 50v x7r ceramic capacitors (0603) tdk c1608x7r1h472k or equivalent c22, c32, c33 0 not installed; 1f 10%, 16v x5r ceramic capacitors (0603) panasonic ecj1vb1c105k or equivalent (tripler) c23 1 6800pf 10%, 25v x7r ceramic capacitor (0402) murata grp155r71e682k or equivalent c24 1 not installed, 10pf ceramic capacitor (0402) c25, c39 2 0.22f 10%, 6.3v x5r ceramic capacitors (0402) tdk c1005x5r0j224k or equivalent c26, c27, c28 3 10f 20%, 6.3v x5r ceramic capacitors (0805) panasonic ecj2fb0j106m or equivalent c29 1 4.7f 10%, 6.3v x5r ceramic capacitor (0603) panasonic ecj1vb0j475k or equivalent c30 1 0.1f 10%, 10v x5r ceramic capacitor (0402) tdk c1005x5r1a104k or equivalent c31 1 1f 20%, 6.3v x5r ceramic capacitor (0402) panasonic ecj0eb0j105m or equivalent c34 1 1f 10%, 16v x5r ceramic capacitor (0603) panasonic ecj1vb1c105k or equivalent c35 1 470f, 6.3v poscap sanyo 6tpb470m designation qty description c36 1 not installed (0805) d6 1 single schottky diode (sot-323) central cmssh-3 d7 d10 4 not installed, schottky diodes (sod-123) central cmhsh5-2l (tripler) ju5 1 4-pin 3-way header ju6, ju7 2 3-pin headers ju8 1 2-pin header l2 1 0.45h inductor sumida cdep105(s)-0r4mc-50 n3 1 n-channel mosfet (d-pak) irf irlr7821 n4 1 n-channel mosfet (d-pak) irf irlr7833 r6 1 10k ? 1% resistor (0603) r7 1 12.4k ? 1% resistor (0603) r8 1 20k ? 5% resistor (0603) r9 1 1.5m ? 5%, 1w resistor (2512) panasonic erjm1wtj1m5u r10 1 10 ? 5% resistor (0603) r11 1 not installed (0603) r14, r15 2 1 ? 5% resistors (0603) u2 1 max1962eep (20-pin qsop) none 3 shunts the following components are for the optional max1962 circuit and are not installed: supplier phone website central semiconductor 631-435-1110 www.centralsemi.com international rectifier 310-322-3331 www.irf.com kamaya 260-489-1533 www.kamaya.com murata 814-237-1431 www.murata.com panasonic 714-373-7939 www.panasonic.com sanyo 619-661-6835 www.sanyo.com sumida 847-545-6700 www.sumida.com tdk 847-803-6100 www.component.tdk.com component suppliers note: please specify that you are using the max1960/ max1961/max1962 when contacting these suppliers.
quick start the max1960 ev kit is fully assembled and tested. follow these steps to verify board operation. do not turn on the power supply until all connections are completed: 1) verify jumpers ju1, ju2, and ju3 are shorted between pins 2 and 3. 2) preset input power supply to between 2.7v and 5.5v. turn power supply off. 3) connect the positive power-supply lead to the in1 pad on the ev kit. connect the supply ground to the pgnd1 pad on the ev kit. 4) connect a voltmeter and load from out1 to pgnd1 on the ev kit. 5) turn on the power supply. 6) verify that the voltage at out1 is +1.8v 1.5%. jumper selection detailed description evaluating the max1961 or max1962 the max1960 ev kit comes with the max1960 installed, but can also be used to evaluate the max1961 and the max1962. free samples of these parts can be obtained from maxim. to evaluate the max1961, first carefully remove u1 from the pc board and replace it with the max1961. next, remove feedback resistors r3 and r4. finally, short the pads of r3. the evaluation kit is now config- ured for the max1961. to evaluate the max1962, a second circuit is provided on the pc board. components for this circuit do not come installed on the standard evaluation kit board. to configure the board for the max1962, install the com- ponents recommended in the component list section. evaluates: max1960/max1961/max1962 max1960 evaluation kit _______________________________________________________________________________________ 3 ju1 position ju2 position out1 function 1-2 1-2 shutdown 1-2 2-3 -4% margining 2-3 1-2 +4% margining 2-3 2-3 enable (normal operation) table 1. ju1 and ju2 functions (max1960/max1961) jumper position operating frequency 1-2 500khz 2-3 1mhz not connected clock applied to sync_ input table 2. ju3 and ju6 functions jumper position output voltage 1-2 +1.5v 1-3 +1.8v 1-4 +3.3v not connected +2.5v table 3. ju4 and ju5 functions (max1961/max1962) jumper position out2 function 1-2 shutdown 2-3 enable table 4. ju7 functions (max1962) jumper position out2 voltage 1-2 selected with ju5 not connected adjustable set with resistors r6 and r7 table 5. ju8 functions jumper pads charge pump open 2x (normal) short 3x (tripler) table 6. ju9 and ju11 functions jumper pads function open ju1 and ju2 function as shown in table 1 short ctl1 and ctl2 connected use only one jumper on ju1 or ju2 for shutdown/enable table 7. ju10 functions (max1960/max1961) jumper pads function open uses inductor resistance for current sensing short uses current-sense resistor table 8. ju12 functions (max1962)
evaluates: max1960/max1961/max1962 setting the output voltage (max1960/max1962) the max1960 uses a pair of feedback resistors to set the output voltage, which is fixed at +1.8v from the fac- tory. the output voltage of the max1962 can also be set with feedback resistors, or can use its preset output voltages like the max1961 (see the selecting a preset output voltage section). to change the output voltage on the max1960 circuit, first verify that a 10k ? resistor is installed in r4. then calculate a resistor value for r3: to set the output voltage on the max1962 circuit, first remove jumper ju8. then, install a 10k ? resistor in r6. finally, calculate a resistor value for r7: when changing the output-voltage setting, refer to the max1960/max1961/max1962 data sheet for selecting compensation components, output inductor, and output capacitor for best performance. selecting a preset output voltage (max1961/max1962) first, follow the procedure given under the evaluating the max1961 or max1962 section to set up the ev kit for using the max1961 or max1962. to select a preset output voltage with the max1962, short the pins of jumper ju8, remove resistors r6 and r7, and use ju5 to select the output voltage (table 3). for the max1961, use ju4 to select the output voltage (table 3). when selecting different output voltages, refer to the max1960/max1961/max1962 data sheet for selecting compensation components, output inductor, and output capacitor for best performance. evaluating at low input voltages (tripler configuration) in the default configuration, the ev kit works at input voltages from +2.7v to +5.5v. to work with input volt- ages below +2.7v, configure the charge pump as a tripler. when using the tripler, the input voltage range is +2.35v to +3.6v. to configure the charge pump as a tripler, use the following procedure: for the max1960/max1961 circuit: 1) remove c1. 2) add c2, c3, and c13 (see the component list ). 3) add d2 d5 (see the component list ). 4) short the pads of ju9. for the max1962 circuit: 1) remove c34. 2) add c22, c32, and c33 (see the component list ). 3) add d7 d10 (see the component list ). 4) short the pads of ju11. changing the switching frequency ju3 and ju6 select between 500khz and 1mhz opera- tion. to optimize performance, it is also necessary to change the value of some of the components. the components for 1mhz operation come installed on the pc board (max1960/max1961 circuit), and are listed in the component list table. for 500khz operation, change the components listed in table 9, and refer to the max1960/max1961/max1962 data sheet for select- ing compensation components. the max1962 circuit component list is configured for 500khz operation. rr v out 76 08 1 = ? ? ? ? ? ? ? . rr v out 34 08 1 = ? ? ? ? ? ? ? . max1960 evaluation kit 4 _______________________________________________________________________________________ designation (max1960/max1961) qty description notes c1 1 1f 10%, 16v x5r ceramic capacitor (0603), panasonic ecj1vb1c105k without tripler c2, c3, c13 3 1f 10%, 16v x5r ceramic capacitors (0603), panasonic ecj1vb1c105k with tripler c6 1 4.7f 10%, 6.3v x5r ceramic capacitor (0603), panasonic ecj1vb0j475k l1 1 0.45h inductor, sumida cdep105(s)-0r4mc-50 table 9. component changes for 500khz operation
using sync and clkout to synchronize the converter to an external clock, connect the clock signal (450khz to 1.1mhz) to sync_. a clock output (clkout_) is provided on the ev kit. clkout_ functions both when the converter is switch- ing at its preset frequency and when a sync signal is applied. the clkout_ waveform is 180 out-of-phase with the converter s clock, allowing a second converter to operate out-of-phase with the first by connecting clkout_ of the first converter to sync_ of the second converter. evaluating voltage margining (max1960/max1961) a voltage-margining feature is provided on the max1960 and max1961. this allows the output to be shifted up or down by 4%. voltage margining is controlled by ju1 and ju2 ( table 1). evaluating shutdown shutdown mode turns off the ic, reducing the input current to below 10a. for the max1960/max1961, ju1 and ju2 control the shutdown feature ( table 1). on the max1962, ju7 controls shutdown ( table 4). if voltage margining is not used on the max1960/ max1961, then the pads of ju10 can be connected together to allow shutdown/enable using a single jumper. if this is done, either ju1 or ju2 must be completely removed and the other used to control shutdown/enable. connecting both jumpers can cause an input supply to ground short, which could damage the ev kit. evaluates: max1960/max1961/max1962 max1960 evaluation kit _______________________________________________________________________________________ 5
evaluates: max1960/max1961/max1962 max1960 evaluation kit 6 _______________________________________________________________________________________ max1960 in1 pgnd1 sync1 c7 10 f c8 10 f c9 10 f c37 470 f c38 0.22 f 3 2 1 ju2 3 2 1 ju1 ju10 ju9 3 2 1 ju3 c12 0.01 f c11 10pf c10 0.22 f r1 301k ? r2 6.8k ? r5 10 ? ref clkout1 3 4 2 1 ju4 vdd ref c3 0.47 f c2 0.47 f c1 0.47 f c16 4700pf c17 4700pf c4 1 f c6 2.2 f c13 0.47 f c5 0.1 f vcc vcc vdd d2 d3 d4 d5 n1 n2 r12 1 ? r3 12.4k ? r4 10k ? r13 1 ? vdd d1 2 3 l1 0.22 h c14 680 f c15 680 f out1 pgnd1 v cc ctl1 ctl2 comp ref ilim gnd fset/sync clkout n.c. c- dh v dd bst lx dl pgnd fb av dd c+ 17 5 6 9 10 11 2 1 4 3 16 15 7 19 12 18 20 13 14 8 u1 max1962 in2 pgnd2 sync2 c28 c27 c26 c35 c39 3 2 1 ju7 ju11 3 2 1 ju6 c23 r8 c24 c25 r10 ref2 clkout2 3 4 2 1 ju5 vdd ref2 c32 c33 c34 c20 c21 c31 c22 c30 c29 vcc2 vcc2 vdd2 d7 d8 d9 d10 n3 n4 r14 r6 r7 r15 r11 ju12 ju8 c36 d6 2 3 l2 0.22 h r9 c18 c19 out2 pgnd2 v cc en comp ref gnd fset/sync clkout vsel c- dh v dd bst lx dl pgnd cs av dd c+ 17 3 9 10 11 2 1 4 16 15 7 19 12 18 20 13 14 6 out 5 fb 8 u2 vdd2 vdd2 figure 1. max1960 ev kit schematic
evaluates: max1960/max1961/max1962 max1960 evaluation kit _______________________________________________________________________________________ 7 figure 2. max1960 ev kit component placement guide component side figure 3. max1960 ev kit pc board layout?omponent side figure 4. max1960 ev kit pc board layout?ayer 2 (ground)
evaluates: max1960/max1961/max1962 max1960 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 ? 2003 maxim integrated products printed usa is a registered trademark of maxim integrated products. figure 5. max1960 ev kit pc board layout?ayer 3 figure 6. max1960 ev kit pc board layout?older side
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