19-0785; Rev 1; 10/07 KIT ATION EVALU E L B A AVAIL High-Voltage, Dual-Input, USB/AC Adapter Chargers in 2mm x 3mm TDFN The MAX8804W/MAX8804Y/MAX8804Z intelligent, dual-input, stand-alone, constant-current, constant-voltage (CCCV), thermally regulated linear chargers are designed for a single-cell lithium-ion (Li+) battery. They integrate the current-sense circuit, MOS pass element, thermal-regulation circuitry, and overvoltage protection (OVP), and eliminate the reverse-blocking Schottky diode to create a simple and small charging solution for handheld equipment. The MAX8804W/MAX8804Z function as stand-alone chargers to control the charging sequence from the prequalification state through fast-charge, top-off charge, and full-charge indication. The MAX8804Y eliminates the prequalification state to allow startup into a load without a battery. Proprietary thermal-regulation circuitry limits the die temperature when fast-charging or while exposed to high ambient temperatures, allowing maximum charging current without damaging the IC. The MAX8804Y/MAX8804Z achieve high flexibility by providing an adjustable DC/USB fast-charge current through a simple single-wire interface (SET input). The chargers automatically select between either a USB or AC adapter input source. The AC adapter charge current is programmable from 400mA to 700mA in 50mA steps through a serial interface. The USB charge current is programmable to 95mA, 380mA, or 475mA through the same interface. Other features include an active-low battery charging-status indicator (CHG), an active-low power-OK indicator (POK), an active-low USB input detection output (USBPWR) on the MAX8804Y/MAX8804Z, and battery pack detection (DETBAT) on the MAX8804W. The MAX8804W/MAX8804Y/MAX8804Z accept a 4.15V to 30V DC source voltage or a 4.15V to 16V USB input voltage, but disable charging when either input voltage exceeds 7.5V to protect against unqualified or faulty input sources. The MAX8804W/MAX8804Y/MAX8804Z operate over the extended temperature range (-40°C to +85°C) and are available in a tiny 8-pin thermally enhanced 2mm x 3mm TDFN package. Features ♦ Complete Chargers for Single-Cell Li+ Battery ♦ Dual-Input, 30V AC Adapter/16V USB ♦ No External FET, Blocking Diode, or Sense Resistor Required ♦ Automatic USB/AC Adapter Input Selection ♦ Easy Programmable Fast-Charge Current and Top-Off Threshold ♦ Proprietary Die Temperature Regulation Control ♦ ±5% Fast-Charge Current-Limit Accuracy ♦ Battery Pack Detection Input (MAX8804W) ♦ Power-Present and Charger-Status Outputs ♦ No Prequalification Charge (MAX8804Y) ♦ Tiny 2mm x 3mm Thermally Enhanced TDFN Package ♦ USB Charging Protected by US Patent #6,507,172 Ordering Information PART PINPACKAGE PKG CODE TOP MARK MAX8804WETA+ 8 TDFN-EP* T823+1 AAP MAX8804YETA+ 8 TDFN-EP* T823+1 AAD MAX8804ZETA+ 8 TDFN-EP* T823+1 AAC *EP = Exposed paddle. +Denotes a lead-free package. Note: All devices are specified to operate over the -40°C to +85°C operating temperature range. Typical Application Circuit +3.3V AC ADAPTER DC 1μF GND Applications Cell Phones/Smartphones USB PORT USB 1μF MAX8804W MAX8804Y MAX8804Z CHG POK <USBPWR> (DETBAT) Digital Cameras Portable Media Players MP3 Players Other Handheld Devices BAT ENABLE/DISABLE AND PROGRAMMING 2.2μF Li+ SET NOTE: () FOR MAX8804W, < > FOR MAX8804Y/MAX8804Z Pin Configuration appears at end of data sheet. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com. 1 MAX8804W/MAX8804Y/MAX8804Z General Description MAX8804W/MAX8804Y/MAX8804Z High-Voltage, Dual-Input, USB/AC Adapter Chargers in 2mm x 3mm TDFN ABSOLUTE MAXIMUM RATINGS DC to GND .............................................................-0.3V to +30V USB to GND ...........................................................-0.3V to +16V BAT, CHG, SET, POK, USBPWR, DETBAT to GND...............................................................-0.3V to +5.5V Continuous Power Dissipation (TA = +70°C) 8-Pin TDFN 2mm x 3mm (derate 16.7mW/°C above +70°C) (multilayer board) .......................................................1333mW Operating Temperature Range ...........................-40°C to +85°C Junction Temperature ......................................................+150°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS ((VDC = 5V, VSET = 0V) or (VUSB = 5V, VSET = 5V), VBAT = unconnected, VDETBAT = 0V (MAX8804W), TA = -40°C to +85°C, unless otherwise noted.) (Note 1) PARAMETER CONDITIONS MIN TYP MAX UNITS DC AND USB DC Input Voltage Range 0 28 V USB Input Voltage Range 0 14 V (Notes 2, 3) 4.15 7.00 V Input Undervoltage Threshold VIN rising, 500mV hysteresis (typ) (Note 2) 3.85 4.0 4.15 V Input Overvoltage Threshold VIN rising, 200mV hysteresis (typ) (Note 2) 7.2 7.5 7.8 V VUSB = 0V, IBAT = 0mA, charge mode 800 1200 VSET = 5V, standby mode 300 550 VDC = VBAT = 4.3V, shutdown mode 300 550 VDC = 0V, VSET = 5V, IBAT = 0mA, charge mode 800 1200 Input Operating Range DC Input Supply Current USB Input Supply Current DC to BAT On-Resistance µA µA VSET = 0V, standby mode 300 550 VUSB = VBAT = 4.3V, shutdown mode 300 550 VDC = 3.7V, VBAT = 3.6V 0.55 1.0 Ω 0.65 1.2 Ω 260 385 USB to BAT On-Resistance VUSB = 3.7V, VBAT = 3.6V Input to BAT Comparator Threshold (Note 2) VIN rising 145 VIN falling 55 mV BAT BAT Regulation Voltage IBAT = 0mA Battery Removal Detection Threshold VBAT rising 2 Hysteresis TA = +25°C 4.179 4.200 4.221 TA = -40°C to +85°C 4.158 4.200 4.242 4.40 4.67 4.90 0.1 _______________________________________________________________________________________ V V High-Voltage, Dual-Input, USB/AC Adapter Chargers in 2mm x 3mm TDFN ((VDC = 5V, VSET = 0V) or (VUSB = 5V, VSET = 5V), VBAT = unconnected, VDETBAT = 0V (MAX8804W), TA = -40°C to +85°C, unless otherwise noted.) (Note 1) PARAMETER CONDITIONS VUSB = 0V, VBAT = 3.6V, rising edge detection on SET (MAX8804Y/ MAX8804Z) DC Charging Current VUSB = 0V, VBAT = 3.6V, rising edge detection on SET (MAX8804W) USB Charging Current Default and 1st to 3rd interface pulse MIN TYP MAX 475 500 525 4th to 7th interface pulse 523 550 578 8th to 11th interface pulse 570 600 630 12th to 15th interface pulse 428 450 473 16th to 19th interface pulse 380 400 420 20th to 23rd interface pulse 618 650 683 24th to 27th interface pulse 665 700 735 Default and 1st to 3rd interface pulse 428 450 473 4th to 7th interface pulse 523 550 578 8th to 11th interface pulse 475 500 525 12th to 15th interface pulse 380 400 420 16th to 19th interface pulse 570 600 630 20th to 23th interface pulse 618 650 683 24th to 27th interface pulse 665 700 735 VDC = 0V, VBAT = 3.6V, rising edge detection on SET (MAX8804Y/ MAX8804Z) Default 90 95 100 1st interface pulse 360 380 400 2nd interface pulse 450 475 500 VDC = 0V, VBAT = 3.6V, rising edge detection on SET (MAX8804W) Default 360 380 400 1st interface pulse 450 475 500 2nd interface pulse 90 95 100 UNITS mA mA Soft-Start Time Ramping time from 0 to 500mA BAT Prequal Threshold MAX8804W/MAX8804Z only, VBAT rising, 300mV hysteresis (typ) BAT Prequal Charge Current MAX8804W/MAX8804Z only BAT Leakage Current VDC = VUSB = 0V, VBAT = 4.2V 250 2.35 2.50 µs 2.65 95 V mA 2 µA SET Logic Input Thresholds VSET rising VSET falling 1.6 0.4 Logic-High Time Pulse width required to program DC charge current Logic-Low Time Pulse width required to program USB charge current 1000 µs SET DC Mode Shutdown Delay VUSB = 0V, VDC = 5V, measured from VSET low to high 1.5 2 2.5 ms SET USB Mode Shutdown Delay VDC = 0V, VUSB = 5V, measured from VSET high to low 1.5 2 2.5 ms 2 4 MΩ SET Internal Pulldown Resistor 1 1000 V 1 µs _______________________________________________________________________________________ 3 MAX8804W/MAX8804Y/MAX8804Z ELECTRICAL CHARACTERISTICS (continued) MAX8804W/MAX8804Y/MAX8804Z High-Voltage, Dual-Input, USB/AC Adapter Chargers in 2mm x 3mm TDFN ELECTRICAL CHARACTERISTICS (continued) ((VDC = 5V, VSET = 0V) or (VUSB = 5V, VSET = 5V), VBAT = unconnected, VDETBAT = 0V (MAX8804W), TA = -40°C to +85°C, unless otherwise noted.) (Note 1) PARAMETER CONDITIONS MIN TYP MAX UNITS 60 500 mV TA = +25°C 0.001 1 TA = +85°C 0.01 POK, CHG, USBPWR (USBPWR only for MAX8804Y/MAX8804Z) Logic Output-Voltage Low I POK = I CHG = I USBPWR = 5mA Logic Output-Current High V POK = V CHG = V USBPWR = 5.5V, VDC = VUSB = 0V µA DETBAT (MAX8804W only) Logic Input Theshold Rising 1.6 Falling 0.4 Pullup Resistor 63 V kΩ CHG VDC = 0V, VUSB = 5V 60 80 100 60 80 100 67.5 90 112.5 2nd, 6th, 10th, 14th, 18th, 22nd, 26th interface pulse 75 100 125 3rd, 7th, 11th, 15th, 19th, 23rd, 27th interface pulse 52.7 70 87.5 Default, 4th, 8th, 12th, 16th, 20th, 24th, 28th interface pulse CHG Top-Off Threshold IBAT falling, battery is charged, rising edge on SET VDC = 5V, VUSB = 0V 1st, 5th, 9th, 13th, 17th, 21st, 25th interface pulse DC mode 57 USB mode 51 CHG Hysteresis IBAT rising after top-off is detected (Note 4) CHG Detection Delay IBAT falls below top-off threshold 3 4 mA mA 5 ms THERMAL LOOP Thermal-Regulation Set Point Junction temperature when the charge current is reduced, TJ rising Thermal-Regulation Gain Reduction of IBAT for increase of TJ +105 DC charging -40 USB charging -24 °C mA/°C Note 1: Devices are 100% production tested at TA = +25°C. Limits over the operating temperature range are guaranteed by design and characterization. Note 2: VIN refers to the input for the IC. For the MAX8804W/MAX8804Y/MAX8804Z, VIN is VDC with VUSB = 0V or VUSB with VDC = 0V. Note 3: Guaranteed by undervoltage and overvoltage threshold testing. For charge completion, the input voltage must be greater than 4.28V. Note 4: This hysteresis is for all charge current except 95mA. In the case of 95mA charge current, voltage-mode to current-mode detection gives indication of charge mode. 4 _______________________________________________________________________________________ High-Voltage, Dual-Input, USB/AC Adapter Chargers in 2mm x 3mm TDFN SUPPLY CURRENT vs. INPUT VOLTAGE (USB CHARGING MODE) SUPPLY CURRENT vs. INPUT VOLTAGE (DC CHARGING MODE) 0.6 0.4 0.6 0.4 0.2 0.2 0 0 3 6 0 9 12 15 18 21 24 27 30 INPUT VOLTAGE (V) DISABLED-MODE SUPPLY CURRENT vs. INPUT VOLTAGE (DC CHARGING MODE) 0.4 0.2 6 8 10 12 INPUT VOLTAGE (V) 14 0.8 MAX8804Y/Z toc03 0.6 4 16 STANDBY-MODE SUPPLY CURRENT vs. INPUT VOLTAGE (USB CHARGING MODE) SUPPLY CURRENT (mA) 0 0.6 0.4 0.2 0 0 5 10 15 20 INPUT VOLTAGE (V) 25 30 0 200 MAX8804Y/Z toc05 160 CHARGE CURRENT (mA) 500 400 300 200 4 6 8 10 12 INPUT VOLTAGE (V) 14 16 CHARGE CURRENT vs. BATTERY VOLTAGE (USB CHARGING MODE) CHARGE CURRENT vs. BATTERY VOLTAGE (DC CHARGING MODE) 600 2 MAX8804Y/Z toc06 SUPPLY CURRENT (mA) 0.8 2 MAX8804Y/Z toc04 0 CHARGE CURRENT (mA) MAX8804Y/Z toc02 0.8 SUPPLY CURRENT (mA) 0.8 SUPPLY CURRENT (mA) 1.0 MAX8804Y/Z toc01 1.0 120 80 40 100 0 0 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 BATTERY VOLTAGE (V) 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 BATTERY VOLTAGE (V) _______________________________________________________________________________________ 5 MAX8804W/MAX8804Y/MAX8804Z Typical Operating Characteristics (VBAT = 3.6V; DC charge mode: VDC = 5V, VUSB = 0V, VDETBAT = 0V (only for MAX8804W), VSET = 0V or unconnected; USB charge mode: VUSB = 5V, VDC = 0V, VSET = 5V; TA = +25°C, unless otherwise noted.) Typical Operating Characteristics (continued) (VBAT = 3.6V; DC charge mode: VDC = 5V, VUSB = 0V, VDETBAT = 0V (only for MAX8804W), VSET = 0V or unconnected; USB charge mode: VUSB = 5V, VDC = 0V, VSET = 5V; TA = +25°C, unless otherwise noted.) CHARGE CURRENT vs. DC INPUT VOLTAGE CHARGE CURRENT vs. USB INPUT VOLTAGE CHARGE CURRENT (mA) 400 300 200 MAX8804Y/Z toc09 MAX8804Y/Z toc08 500 CHARGE CURRENT vs. SET PULSE (USB CHARGING MODE) (MAX8804Y/MAX8804Z) 120 MAX8804Y/Z toc07 600 90 VSET 1V/div 60 475mA 380mA 95mA 95mA 0 10 15 20 INPUT VOLTAGE (V) 25 30 0 2 CHARGE CURRENT vs. SET PULSE (DC CHARGING MODE) (MAX8804Y/MAX8804Z) 4 6 8 10 12 INPUT VOLTAGE (V) 14 600 INPUT VOLTAGE DECREASING 700mA 550mA 650mA 600mA 700mA 200mA/div 450mA 500mA 500mA CHARGE CURRENT (mA) 500 1V/div 400mA BATTERY REGULATION VOLTAGE vs. AMBIENT TEMPERATURE 400 DC MODE 300 200 USB MODE 100 0 2ms/div 100 200 300 400 INPUT VOLTAGE HEADROOM (mV) 4.198 DC MODE 4.192 4.186 500 -40 -15 10 35 60 AMBIENT TEMPERATURE (°C) 500 400 300 MAX8804Y/Z toc14 4.30 BATTERY REGULATION VOLTAGE (V) 600 USB MODE 4.204 BATTERY REGULATION VOLTAGE vs. LOAD CURRENT MAX8804Y/Z toc13 700 4.210 4.180 0 CHARGE CURRENT vs. AMBIENT TEMPERATURE CHARGE CURRENT (mA) 2ms/div CHARGE CURRENT vs. INPUT VOLTAGE HEADROOM MAX8804Y/Z toc10 VSET 16 BATTERY REGULATION VOLTAGE (V) 5 MAX8804Y/Z toc11 0 4.25 4.20 4.15 DC CHARGE MODE 650mA 550mA CHARGE-CURRENT SETTING 4.10 200 -40 6 475mA 200mA/div 95mA 0 380mA ICHG 30 100 ICHG 475mA -15 10 35 60 AMBIENT TEMPERATURE (°C) MAX8804Y/Z toc12 CHARGE CURRENT (mA) MAX8804W/MAX8804Y/MAX8804Z High-Voltage, Dual-Input, USB/AC Adapter Chargers in 2mm x 3mm TDFN 85 0 100 200 300 400 500 LOAD CURRENT (mA) 600 _______________________________________________________________________________________ 700 85 High-Voltage, Dual-Input, USB/AC Adapter Chargers in 2mm x 3mm TDFN PIN MAX8804W MAX8804Y/ MAX8804Z NAME 1 1 BAT Battery Connection. The IC delivers charging current and monitors battery voltage using BAT. Bypass BAT to GND with a 2.2µF or larger ceramic capacitor. BAT is high impedance when the IC is disabled. 2 — DETBAT Battery Pack Detection Input. Drive DETBAT low or connect it to GND to allow SET to control the charger. Leave DETBAT unconnected to disable any charge mode. — 2 USBPWR USB Input Detection Output. USBPWR is internally pulled low if a valid voltage is present at USB, otherwise it is high impedance. USBPWR circuitry is active regardless of SET and charger on/off status. 3 3 POK 4 4 DC DC Input Supply. Connect DC to a 4.15V to 7V charging source. Bypass DC to GND with a 1µF or larger ceramic capacitor. DC takes priority over USB when both are valid. 5 5 USB USB Input Source. Connect USB to a USB port. Bypass USB to GND with a 1µF or larger ceramic capacitor. 6 6 CHG Charging-Status Output. CHG is internally pulled low when the battery is being charged. CHG is high impedance when the charger is in top-off mode or disabled. 7 7 SET 8 8 GND — — EP FUNCTION Power-OK Monitor. POK is an open-drain output that is internally pulled low when a valid charging source is detected at either DC or USB. POK is high impedance when both input voltages are less than VUVLO or VBAT. Enable/Disable, Charging Current, and Top-Off Threshold Set Input. Drive SET low to enable DC charge mode and drive high to enable USB charge mode. If both DC and USB inputs are present, SET is used for the DC charge mode only and USB charge is disabled. SET is also used for programming the charge current and top-off threshold. See the DC/USB Mode and Charging Current Setting section for details. Ground Exposed Paddle. Connect to the GND plane for optimum thermal dissipation. _______________________________________________________________________________________ 7 MAX8804W/MAX8804Y/MAX8804Z Pin Description MAX8804W/MAX8804Y/MAX8804Z High-Voltage, Dual-Input, USB/AC Adapter Chargers in 2mm x 3mm TDFN 4.15V TO 30V BAT DC Li+ 4.15V TO 16V USB +105°C DC AND USB OUTPUT CONTROL TEMP SENSOR VOLTAGE LOOP MAX8804Y MAX8804Z OVERVOLTAGE PROTECTION (DETBAT) DC POK SET CHG POK LOGIC CONTROL <USBPWR> USB POK REF BIAS CIRCUIT GND NOTE: ( ) FOR MAX8804W ONLY < > FOR MAX8804Y/MAX8804Z ONLY Figure 1. Functional Diagram Detailed Description The MAX8804W/MAX8804Y/MAX8804Z dual-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 MAX8804W/MAX8804Z chargers enter the prequalification stage where they precharge that cell with 95mA (Figure 2). The CHG indicator output is driven low to indicate entry into the prequalification state. When battery voltage exceeds 2.5V, the charger softstarts as it enters the fast-charge stage. The MAX8804Y eliminates the prequalification state and enters fastcharge when the battery is inserted. The fast-charge current level is programmed by a simple single-wire 8 interface. As the battery voltage approaches 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 constant voltage-regulation mode to maintain the battery at full charge. The MAX8804W/MAX8804Y/MAX8804Z automatically select between either a USB or AC adapter input source. The AC adapter charge current is programmable from 400mA to 700mA in 50mA steps through a simple singlewire interface (see Tables 2 and 3). The USB charge current is programmable to 95mA, 380mA, or 475mA through the same interface (see Tables 4 and 5). _______________________________________________________________________________________ High-Voltage, Dual-Input, USB/AC Adapter Chargers in 2mm x 3mm TDFN STANDBY MODE CHARGER = OFF POK = LOW CHG = HIGH IMPEDANCE MAX8804W/ MAX8804Z VBAT < 2.5V tSET = LOW > 2ms FOR DC MODE tSET = HIGH > 2ms FOR USB MODE PREQUALIFICATION DEFAULT CHARGE CURRENT POK = LOW CHG = LOW VBAT < 2.2V MAX8804W/ MAX8804Z VUVLO < VIN < VOVP AND VIN > VBAT SHUTDOWN CHARGER = OFF POK = HIGH IMPEDANCE* CHG = HIGH IMPEDANCE VIN < VUVLO OR VIN > VOVP OR VBAT > VIN OR DETBAT = HIGH MAX8804W/MAX8804Y/MAX8804Z ASYNCHRONOUS FROM ANYWHERE tSET = HIGH > 2ms FOR DC MODE tSET = LOW > 2ms FOR USB MODE ASYNCHRONOUS FROM ANYWHERE VIN < VUVLO OR VIN > VOVP OR VBAT > VIN OR DETBAT = HIGH MAX8804Y tSET = LOW > 2ms FOR DC MODE tSET = HIGH > 2ms FOR USB MODE VBAT > 2.5V FAST-CHARGE 100% CHARGE CURRENT POK = LOW CHG = LOW ICHG > ITOP-OFF + 57mA FOR ALL FAST-CHARGE OPTIONS EXCEPT 95mA ICHG < ITOP-OFF CV MODE TO CC MODE FOR 95mA FAST-CHARGE OPTION FULL BAT VBAT = 4.2V POK = LOW CHG = HIGH IMPEDANCE *POK = LOW WHEN VIN > VOVP Figure 2. Charger State Diagram DC Charging USB Charging The MAX8804W/MAX8804Y/MAX8804Z are designed to charge a single-cell Li+ battery from a DC source voltage between 4.15V and 7V and withstand up to 30V maximum input voltage. The charge current and top-off threshold are programmed with the SET input. The MAX8804W/MAX8804Y/MAX8804Z contain a USB input that allows operation from a USB port with voltages between 4.15V and 7V and can withstand up to 16V maximum input voltage. Pulsing SET allows programming a 95mA, 380mA, or 475mA maximum charging current when using the USB input. _______________________________________________________________________________________ 9 MAX8804W/MAX8804Y/MAX8804Z High-Voltage, Dual-Input, USB/AC Adapter Chargers in 2mm x 3mm TDFN DC/USB Mode and Charging Current Setting Table 1. SET Truth Table SET VDC VUSB 0 Invalid Invalid 0 Invalid Valid CHARGER STATUS Off 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 1 Invalid Valid 1 Valid Invalid Off DC charging mode disabled, USB charging mode enabled Off 1 Valid Valid Off Note: This table is true when DETBAT = LOW for the MAX8804W. When DETBAT = HIGH, the MAX8804W enters shutdown. SET is a logic input that sets DC/USB charging mode 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. DC Charge Mode Drive SET low or leave it unconnected 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. Default fast-charge current and topoff threshold current are 500mA and 80mA. Pulse SET high (1µs to 1ms pulse width) subsequently to realize charging current and top-off threshold programming and transition. After the 28th pulse, the MAX8804W/ MAX8804Y/MAX8804Z go into the default mode and start a new cycle. See Tables 2 and 3 and Figure 3 to set the desired charging current and top-off threshold. Drive SET high longer than 2ms to disable the DC charging-control circuitry. Table 2. MAX8804Y/MAX8804Z DC Charging Current Programming by Series Pulses PULSE NUMBER DEFAULT 1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th 11th 12th 13th 14th ICHG (mA) 500 500 500 500 550 550 550 550 600 600 600 600 450 450 450 Top-Off Current Threshold (mA) 80 90 100 70 80 90 100 70 80 90 100 70 80 90 100 PULSE NUMBER — 15th 16th 17th 18th 19th 20th 21st 22nd 23rd 24th 25th 26th 27th 28th ICHG (mA) — 450 400 400 400 400 650 650 650 650 700 700 700 700 500 Top-Off Current Threshold (mA) — 70 80 90 100 70 80 90 100 70 80 90 100 70 80 Table 3. MAX8804W DC Charging Current Programming by Series Pulses PULSE NUMBER DEFAULT 1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th 11th 12th 13th 14th ICHG (mA) 450 450 450 450 550 550 550 550 500 500 500 500 400 400 400 Top-Off Current Threshold (mA) 80 90 100 70 80 90 100 70 80 90 100 70 80 90 100 PULSE NUMBER — 15th 16th 17th 18th 19th 20th 21st 22nd 23rd 24th 25th 26th 27th 28th ICHG (mA) — 400 600 600 600 600 650 650 650 650 700 700 700 700 450 Top-Off Current Threshold (mA) — 70 80 90 100 70 80 90 100 70 80 90 100 70 80 10 ______________________________________________________________________________________ High-Voltage, Dual-Input, USB/AC Adapter Chargers in 2mm x 3mm TDFN MAX8804W/MAX8804Y/MAX8804Z DC POK 1 2 3 4 24 25 26 27 28 > 2ms SET tHIGH 2ms tSOFTSTART DELAY 500mA (450mA) ICHG 700mA (700mA) 550mA (550mA) 500mA (450mA) 0mA 0mA TOP-OFF CURRENT THRESHOLD 90mA 100mA 90mA 80mA 80mA 80mA 70mA 100mA 70mA 80mA NOTE: ( ) FOR MAX8804W Figure 3. DC Charging Current and Top-Off Threshold Programming USB Charge Mode Drive SET high to enable USB charging mode when the USB input is valid. Subsequent low pulses with 1µs to 1ms pulse width on SET program the fast charging current from 95mA, 380mA, to 475mA and then repeat new cycle as shown in Tables 4 and 5. Drive SET low or leave it unconnected longer than 2ms to disable USB charging-control circuitry. Table 4. MAX8804Y/MAX8804Z USB Charging Current Programming by Series Pulses PULSE NUMBER DEFAULT 1st 2nd 3rd ICHG (mA) 95 380 475 95 Top-Off Current Threshold (mA) 80 80 80 80 Table 5. MAX8804W USB Charging Current Programming by Series Pulses PULSE NUMBER DEFAULT 1st 2nd 3rd ICHG (mA) 380 475 95 380 Top-Off Current Threshold (mA) 80 80 80 80 ______________________________________________________________________________________ 11 MAX8804W/MAX8804Y/MAX8804Z High-Voltage, Dual-Input, USB/AC Adapter Chargers in 2mm x 3mm TDFN USB POK USBPWR 1 2 3 > 2ms SET tLOW 2ms t DELAY SOFTSTART MAX8804Y/ MAX8804Z ICHG 475mA 380mA 95mA 0mA 95mA 0mA 475mA 380mA 380mA MAX8804W ICHG 95mA 0mA 0mA 80mA TOP-OFF CURRENT THRESHOLD Figure 4. USB Charging Current Programming Soft-Start Charging-Status Output (CHG) The soft-start circuitry activates when entering fastcharge mode. In the MAX8804Y, soft-start is entered directly after being enabled, and the charging current ramps up in 250µs from 0 to 500mA (95mA in USB mode). This reduces the inrush current on the input supply. Note that the MAX8804W/MAX8804Z has a prequalification state and the charging current ramps up when the prequalification state is complete (V BAT exceeds 2.5V). CHG is an open-drain output that indicates charger status. CHG goes low during charge cycles where the MAX8804W/MAX8804Y/MAX8804Z are in prequalification or fast-charge mode. CHG goes high impedance when the charge current reaches the top-off threshold for more than 4ms, indicating charging is done. The CHG status is latched after the top-off threshold is reached. The latch is reset by toggling the SET input, recycling input power, or increasing the charging current to the top-off threshold plus 57mA (typ). When the MAX8804W/MAX8804Y/MAX8804Z are used in conjunction with a microprocessor (µP), connect a pullup resistor between CHG and the logic I/O voltage to indicate charge status to the µP. Alternatively, CHG can sink up to 5mA for an LED charge indicator. Thermal Regulation Control The thermal-regulation loop limits the MAX8804W/ MAX8804Y/MAX8804Z die temperature to +105°C 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 temperature without risking damage to the system. 12 ______________________________________________________________________________________ High-Voltage, Dual-Input, USB/AC Adapter Chargers in 2mm x 3mm TDFN USB Power Status Output (USBPWR) (MAX8804Y/MAX8804Z Only) USBPWR is internally pulled low when VUSB > VUVLO and VUSB - VBAT > 250mV. Otherwise, it is high impedance. USBPWR indicates the USB input presence regardless of SET status and charger status. When the MAX8804Y/MAX8804Z are used in conjunction with a µP, connect a pullup resistor between USBPWR and the logic I/O voltage to indicate USB power status to the µP. Alternatively, USBPWR can sink up to 5mA for an LED USB power status indicator. Battery Pack Dectection Input (DETBAT, MAX8804W Only) DETBAT is pulled up to an internal 3V supply through a 63kΩ resistor. Driving DETBAT low or connecting it to GND allows SET to control the charger. When DETBAT is left unconnected, the MAX8804W enters shutdown. Applications Information Capacitor Selection Connect a 2.2µF ceramic capacitor from BAT to GND for proper stability. Connect a 1µF ceramic capacitor from DC to GND. If using the USB input, bypass USB to GND with a 1µF ceramic capacitor. Use a larger input bypass capacitor for high charging currents to reduce supply noise. All capacitors should be X5R dielectric or better. Be aware that some capacitors have large voltage and temperature coefficients and should be avoided. Thermal Considerations The MAX8804W/MAX8804Y/MAX8804Z are available in a thermally enhanced TDFN package with an exposed paddle. Connect the exposed paddle to a large copper ground plane to provide a thermal contact between the device and the PCB for increased power dissipation. The exposed paddle transfers heat away from the device, allowing the IC to charge the battery with maximum current, while minimizing the die temperature increase. Input Sources The MAX8804W/MAX8804Y/MAX8804Z operate from well-regulated input sources. The operating input voltage range is 4.15V to 7V. The device survives DC input supply voltages up to 30V and USB input source voltages up to 16V without damage to the IC. If the input voltage is greater than 7.5V (typ), the IC stops charging. An appropriate power supply must provide at least 4.2V plus the voltage drop across the internal pass transistor when sourcing the desired maximum charging current: VIN(MIN) > 4.2V + ICHARGE(MAX) x RON where R ON is the input-to-BAT resistance (typically 0.55Ω for DC or 0.65Ω for USB). Failure to meet this requirement results in an incomplete charge or increased charge time. Application Circuits Stand-Alone Li+ Charger The MAX8804W/MAX8804Y/MAX8804Z provide a complete Li+ charging solution. The Typical Application Circuit shows the MAX8804W/MAX8804Y/MAX8804Z as a stand-alone Li+ battery charger. The LED indicates when either fast-charge or prequalification has begun. When the battery is fully charged, the LED turns off. Microprocessor-Interfaced Li+ Charger Figure 5 shows the MAX8804W/MAX8804Y/MAX8804Z as a µP-interfaced Li+ battery charger. The µP drives SET to enable/disable DC/USB mode charging. CHG can be used to detect the charge status of a battery. Layout and Bypassing Connect the input capacitors as close as possible to the IC. Provide a large copper GND plane to allow the exposed paddle to sink heat away from the IC. Connect the battery to BAT as close as possible to the IC to provide accurate battery voltage sensing. Make all highcurrent traces short and wide to minimize voltage drops. A sample layout is available in the MAX8804Z evaluation kit to speed designs. ______________________________________________________________________________________ 13 MAX8804W/MAX8804Y/MAX8804Z Power-OK Monitor (POK) The MAX8804W/MAX8804Y/MAX8804Z contain an open-drain POK output that goes low when a valid input source is detected at either DC or USB. A valid input source is one whose voltage is greater than 4.15V and exceeds the battery voltage by 250mV. After a valid input has been established, charging is sustained with inputs as low as 3.5V as long as the input voltage remains above the battery voltage by at least 40mV. POK status is maintained regardless of SET status. When the MAX8804W/MAX8804Y/MAX8804Z are used in conjunction with a µP, connect a pullup resistor between POK and the logic I/O voltage to indicate power-OK to the µP. Alternatively, POK can sink up to 5mA for an LED power-OK indicator. MAX8804W/MAX8804Y/MAX8804Z High-Voltage, Dual-Input, USB/AC Adapter Chargers in 2mm x 3mm TDFN SYSTEM I/O AC ADAPTER DC 1μF USB PORT USB CHG MAX8804W MAX8804Y MAX8804Z 1μF POK μP <USBPWR> (DETBAT) BAT Li+ SET 2.2μF GND NOTE: () FOR MAX8804W <> FOR MAX8804Y/MAX8804Z Figure 5. Microprocessor-Interfaced Li+ Charger with the MAX8804W/MAX8804Y/MAX8804Z Chip Information Pin Configuration PROCESS: BiCMOS TOP VIEW GND SET CHG USB 8 7 6 5 MAX8804W MAX8804Y MAX8804Z + 1 2 3 BAT USBPWR POK (DETBAT) 4 DC TDFN 2mm × 3mm () FOR MAX8804W 14 ______________________________________________________________________________________ High-Voltage, Dual-Input, USB/AC Adapter Chargers in 2mm x 3mm TDFN 8L, TDFN.EPS PACKAGE OUTLINE 8L TDFN, EXPOSED PAD, 2x3x0.8mm 21-0174 B 1 2 ______________________________________________________________________________________ 15 MAX8804W/MAX8804Y/MAX8804Z Package Information (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.) MAX8804W/MAX8804Y/MAX8804Z High-Voltage, Dual-Input, USB/AC Adapter Chargers in 2mm x 3mm TDFN Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.) DIMENSIONS SYMBOL A E D A1 L k A2 MIN. 0.70 NOM. 0.75 MAX. 0.80 2.95 3.00 3.05 1.95 0.00 2.00 0.02 2.05 0.05 0.30 0.40 0.20 MIN. 0.20 REF. 0.50 N e b 0.18 8 0.50 BSC 0.25 EXPOSED PAD PACKAGE E2 D2 PKG. CODE MIN. NOM. MAX. MIN. NOM. MAX. T823-1 1.60 1.75 1.90 1.50 1.63 1.75 0.30 PACKAGE OUTLINE 8L TDFN, EXPOSED PAD, 2x3x0.8mm 21-0174 16 ______________________________________________________________________________________ B 2 2 High-Voltage, Dual-Input, USB/AC Adapter Chargers in 2mm x 3mm TDFN REVISION NUMBER REVISION DATE DESCRIPTION 0 4/07 Initial release. 1 10/07 Added MAX8804W and Battery Pack Detection feature. PAGES CHANGED — 1–16 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 ____________________ 17 © 2007 Maxim Integrated Products Heaney is a registered trademark of Maxim Integrated Products, Inc. MAX8804W/MAX8804Y/MAX8804Z Revision History