general description the max8804z evaluation kit (ev kit) is a fully assem-bled and tested pcb that demonstrates the highly inte- grated max8804z linear battery charger for single-cell lithium-ion (li+) batteries. the ev kit safely charges a single li+ battery to 4.2v. the ev kit accepts a 4.15v to 30v dc source voltage or a 4.15v to 16v usb input voltage, but disables charging when either input volt- age exceeds 7.5v to protect against unqualified or faulty input sources. a simple single-wire set input to the ev kit allows the user to enable/disable the charger or program the charge current and top-off threshold. three leds on the ev kit indicate the power-ok, usb power status, and charger status. the max8804z ev kit can also evaluate the max8804v/max8804w/ max8804y. to evaluate the max8804v/max8804w/ max8804y, order a free sample along with this ev kit. features ? complete charger for single-cell li+ battery ? dual-input, 30v ac adapter/16v usb ? no external fet, blocking diode, or senseresistor required ? automatic usb/ac adapter input selection ? easy programmable fast-charge current andtop-off threshold ? proprietary die temperature regulation control ? ?% fast-charge current-limit accuracy ? battery-pack detection input (max8804v/max8804w) ? power-present and charger-status outputs ? no prequalification charge (max8804y) ? tiny 2mm x 3mm thermally enhanced tdfnpackage ? fully assembled and tested evaluates: max8804v/max8804w/max8804y/max8804z max8804z evaluation kit ________________________________________________________________ maxim integrated products 1 19-4090; rev 0; 4/08 for pricing, delivery, and ordering information, please contact maxim direct at 1-888-629-4642, or visit maxim? website at www.maxim-ic.com. component list ordering information part type MAX8804ZEVKIT+ ev kit + denotes lead-free and rohs-compliant. designation qty description c1, c2 2 1? ?0%, 35v x5r ceramiccapacitors (0603) taiyo yuden gmk107bj105ka c3 1 2.2? ?0%, 10v x5r ceramiccapacitor (0603) taiyo yuden lmk107bj225ka c4 1 0.1? ?0%, 10v x5r ceramiccapacitor (0402) taiyo yuden lmk105bj104kv c5 1 33pf ?0%, 50v c0g ceramiccapacitor (0402) taiyo yuden umk105cg330kv d1, d2, d3 3 green ledsagilent hsmg-c150 d4 1 bias resistor transistoron semiconductor dtc144e j1 1 m al e, u s b typ e- b r i g ht- ang l e connector digi-key ae9925-ndassmann au-y1007-r ju1 1 3-pin header sullins ptc36saan digi-key s1012-36-nd designation qty description ju2 1 2-pin header sullins ptc36saan digi-key s1012-36-nd r1, r2, r3 3 330 ?% resistors (0603) r4, r5, r7 3 100k ?% resistors (0402) r6 1 1k ?% resistor (0402) r8 1 4.7k ?% resistor (0603) s1 1 momentary pushbutton switchpanasonic evq-php03t digi-key p8048str-nd u1 1 high-voltage, dual-input, usb/acadapter charger (8 tdfn-ep*) maxim max8804zeta+ (top mark: aac) u2 1 icm7555isa+ ordigi-key lm555cm-nd 1 pcb: max8804z evaluation kit+ * ep = exposed pad. downloaded from: http:///
evaluates: max8804v/max8804w/max8804y/max8804z max8804z evaluation kit 2 _______________________________________________________________________________________ component suppliers note: indicate that you are using the max8804z when contacting these component suppliers. quick start recommended equipment before beginning, the following equipment is needed: two variable 6v power supplies capable of 750ma one voltmeter one-cell li+ battery procedure the max8804z ev kit is a fully assembled and testedsurface-mount pcb. follow the steps below to verify board operation. caution: do not turn on the power supplies until all connections are completed. 1) place the ju1 shunt across pins 1-2 to set the ev kit for dc charge mode. 2) verify that jumper ju2 is open. 3) preset a power supply to 5v and the second power supply to 3.3v. turn off the power supplies. 4) connect the positive lead of the 5v power supply to the dcin pad. connect the negative lead of the 5vpower supply to the gnd pad. 5) connect the positive lead of the 3.3v power supply to the vlogic pad. connect the negative lead ofthe 3.3v power supply to the gnd pad. 6) connect the voltmeter from the bat pad to the gnd pad. 7) turn on the power supplies. 8) verify that the pok led (d2) turns on to indicate power ok. 9) verify that the voltage is 4.2v at the bat pad. 10) observe correct li+ battery polarity. connect the positive terminal of the li+ battery to the bat pad.connect the negative terminal of the li+ battery to the gnd pad. 11) verify that the chg led (d1) turns on. the chg led turns on during prequalification and fast-charge conditions. the chg led turns off when the battery-charging current drops below the top-offthreshold current. 12) turn off the power supplies and disconnect the bat- tery. place the ju1 shunt across pins 2-3 to setusb charge mode. then repeat from step 3 using the usbin pad. detailed description input source the max8804v/max8804w/max8804y/max8804z aredesigned to charge a single-cell li+ battery from a 4.15v to 7.0v dc source voltage or usb input voltage. the ic accepts dc input voltages up to 30v and usb input voltages up to 16v, but disables charging when the input voltage exceeds 7.5v. a male, usb type-b jack is available to connect the max8804z ev kit to a standard 100ma/500ma usb port to power the ev kit. charging profile the max8804v/max8804w/max8804y/max8804zdual-input linear battery chargers use voltage, current, and thermal-control loops to charge and protect a single li+ battery. when a li+ battery with a cell voltage below 2.5v is inserted, the max8804v/max8804w/max8804z charger enters the prequalification stage where it precharges that cell with 95ma. the chg indicator output is driven low to indicate entry into the prequalification state. when bat-tery voltage exceeds 2.5v, the charger soft-starts as it enters the fast-charge state. the max8804y el- iminates the prequalification state and enters fast charge when the battery is inserted. in the max8804v/max8804w/max8804y/max8804z, the fast-charge current level is programmed by a simple single-wire set input. as the battery voltage approach- es 4.2v, the charging current is reduced. if the battery current drops below the top-off current threshold, the chg indicator goes high impedance, signaling that the battery is fully charged. the ics then enter a con-stant voltage-regulation mode to maintain the battery at full charge. supplier phone website agilent technologies 877-424-4536 www.agilent.com digi-key corp. 800-344-4539 www.digikey.com on semiconductor 602-244-6600 www.onsemi.com taiyo yuden 847-925-0888 www.yuden.co.jp downloaded from: http:///
set input set is a logic input for selecting the dc/usb chargingmode and charging current. drive set low or leave it unconnected to enable dc charging mode. drive set high to enable usb charging mode (see table 1). set can also be driven by series pulses to program the charging current in both dc and usb mode. pulse- generating circuitry is included on the ev kit to program the charge current and top-off threshold. with the ju1shunt across pins 1-2, pressing the s1 switch generates pulses to program the dc charging current, as shown in tables 2, 3, and 4. with the ju1 shunt across pins 2-3, pressing the s1 switch generates pulses to program the usb charging current, as shown in tables 5 and 6. refer to the max8804v/max8804w/max8804y/max8804z ic data sheet for timing diagrams. evaluates: max8804v/max8804w/max8804y/max8804z max8804z evaluation kit _______________________________________________________________________________________ 3 set v dc v usb charger status 0 invalid invalid off 0 invalid valid off 0 valid invalid dc charging mode enabled/usb charging mode disabled 0 valid valid dc charging mode enabled/usb charging mode disabled 1 invalid invalid off 1 invalid valid dc charging mode disabled/usb charging mode enabled 1 valid invalid off 1 valid valid off table 1. set truth table pulse number default 1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th 11th 12th 13th 14th i chg (ma) 500 500 500 500 550 550 550 550 600 600 600 600 450 450 450 top-off currentthreshold (ma) 80 90 100 70 80 90 100 70 80 90 100 70 80 90 100 pulse number default 15th 16th 17th 18th 19th 20th 21st 2 2 n d 2 3 r d 24th 25th 26th 27th 28th i chg (ma) 450 400 400 400 400 650 650 650 650 700 700 700 700 500 top-off currentthreshold (ma) 70 80 90 100 70 80 90 100 70 80 90 100 70 80 table 2. max8804y/max8804z dc charging current programming by series pulses note: this table is true when detbat = low for the max8804v/max8804w. when detbat = high, the max8804v/max8804w enter shutdown. downloaded from: http:///
evaluates: max8804v/max8804w/max8804y/max8804z dc charging mode the max8804v/max8804w/max8804y/max8804zautomatically select between either a usb or ac adapter input source. drive set low or leave it uncon- nected to enable dc charging mode. subsequent pulses on set program the charging current and the top-off threshold. there are seven fast-charge current options and four top-off threshold options. pulse set high (1? to 1ms pulse width) subsequently to realize charging current and top-off threshold programming and transition. after the 28th pulse, the max8804v/ max8804w/max8804y/max8804z return to the default mode and start a new cycle. see tables 2, 3, and 4 to set the desired charging current and top-off threshold. drive set high longer than 2ms to disable dc charging control circuitry. usb charging mode drive set high to enable usb charging mode when theusb input is valid. subsequent low pulses with 1? to 1ms pulse width on set program the fast-charging cur- rent from 95ma, 380ma, to 475ma for the max8804y/ max8804z, and from 380ma, 475ma, to 95ma for the max8804v/max8804w, and then repeat a new cycle as shown in tables 5 and 6. drive set low or leave it unconnected longer than 2ms to disable usb charging control circuitry. max8804z evaluation kit 4 _______________________________________________________________________________________ pulse number default 1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th 11th 12th 13th 14th i chg (ma) 450 450 450 450 550 550 550 550 500 500 500 500 400 400 400 top - o ff c ur r ent thr eshol d ( m a) 120 140 180 200 120 140 180 200 120 140 180 200 120 140 180 pulse number 15th 16th 17th 18th 19th 20th 21st 2 2 n d 2 3 r d 24th 25th 26th 27th 28th i chg (ma) 400 600 600 600 600 650 650 650 650 700 700 700 700 450 top - o ff c ur r ent thr eshol d ( m a) 200 120 140 180 200 120 140 180 200 120 140 180 200 120 table 4. max8804v dc charging current programming by series pulses pulse number default 1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th 11th 12th 13th 14th i chg (ma) 450 450 450 450 550 550 550 550 500 500 500 500 400 400 400 top - o ff c ur r ent thr eshol d ( m a) 80 90 100 70 80 90 100 70 80 90 100 70 80 90 100 pulse number 15th 16th 17th 18th 19th 20th 21st 2 2 n d 2 3 r d 24th 25th 26th 27th 28th i chg (ma) 400 600 600 600 600 650 650 650 650 700 700 700 700 450 top - o ff c ur r ent thr eshol d ( m a) 70 80 90 100 70 80 90 100 70 80 90 100 70 80 table 3. max8804w dc charging current programming by series pulses downloaded from: http:///
charging-status output ( chg ) the chg led (d1) indicates charging status. the led is on ( chg low) when the charger is in the prequalifica- tion or fast-charge mode. it is off ( chg high imped- ance) when the charger reaches the top-off mode formore than 4ms, indicating that charging is done. power-ok output ( pok ) the pok led (d2) is a visual indicator of power-ok status. when a valid input at either dc or usb isdetected greater than 4.15v and exceeds the battery voltage by 250mv, pok pulls low to indicate that the input power is ok. otherwise, pok is high impedance. pok status is maintained regardless of set status. usb power status output ( usbpwr ) (max8804y/max8804z only) the usbpwr led (d3) indicates usb power status output. the led is on ( usbpwr low) when v usb > v uvlo and v usb - v bat > 250mv. otherwise, it is high impedance. usbpwr indicates the usb input presence regardless of set status and charger status. battery pack detection input (detbat) (max8804v/max8804w only) the detbat input is pulled up to an internal 3v supplythrough a 63k resistor. installing a shunt on jumper ju2 allows set to control the charger. the max8804v/max8804w enter shutdown when the shunt on jumper ju2 is removed. thermal-regulation control the thermal-regulation loop limits the max8804v/max8804w/max8804y/max8804z die temperature to +105? by reducing the charge current as necessary. this feature not only protects the ics from overheating, but also allows a higher charge current at room temper- ature, without risking damage to the system. evaluating the max8804v/max8804w/max8804y for evaluating the max8804v/max8804w/max8804y,carefully remove the max8804z ic (u1) and install the max8804v/max8804w/max8804y ic. all other compo- nents remain the same. evaluates: max8804v/max8804w/max8804y/max8804z max8804z evaluation kit _______________________________________________________________________________________ 5 pulse number default 1st 2nd 3rd i chg (ma) 95 380 475 95 top-off currentthreshold (ma) 80 80 80 80 table 5. max8804y/max8804zusb charging current programming by series pulses pulse number default 1st 2nd 3rd i chg (ma) 380 475 95 380 top-off currentthreshold (ma) 80 80 80 80 table 6. max8804v/max8804wusb charging current programming by series pulses downloaded from: http:///
evaluates: max8804v/max8804w/max8804y/max8804z max8804z evaluation kit 6 _______________________________________________________________________________________ max8804z usb 5 d1 r1 330 c2 1 f 6 chg chg 3 pok pok 2 usbpwr usbpwr /detbat 7 set set d4dtc144e usbin dc 4 c1 1 f dcin bat 1 c3 2.2 f c4 0.1 f s1 bat gnd 8 gnd u1 ep 4 3 3 3 21 output trigger 2 1 threshold 6 discharge r61k 7 8 u2 icm7555 gnd vcc ju1 c5 33pf d2 r2 330 d3 r3 330 vlogic +3.3v +3.3v r7 100k r5 100k r4 100k j1 4 3 2 1 1 2 ju2 r84.7k figure 1. max8804z ev kit schematic downloaded from: http:///
maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim product. no circuit patent licenses are implied. maxim reserves the right to change the circuitry and specifications without notice at any time. maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 _____________________ 7 2008 maxim integrated products is a registered trademark of maxim integrated products, inc. evaluates: max8804v/max8804w/max8804y/max8804z max8804z evaluation kit figure 2. max8804z ev kit component placement guide component side figure 3. max8804z ev kit pcb layout?op layer figure 4. max8804z ev kit pcb layout?ottom layer downloaded from: http:///
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