SC802A

SC802 SEMTECH | Alldatasheet

Document overview

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Technical content

Features

Applications

Typical Application Circuit ‹ Fully integrated charger with FET pass transistor, reverse-blocking diode, sense resistor, timer, and thermal protection ‹ Complete voltage ranges of 4.1V, 4.2V & adjust- able ‹ Programmable precharge, fastcharge & termina- tion current ‹ Battery voltage controlled to 1% accuracy ‹ Soft-start for glitch-free adaptor plug-in ‹ Up to 1A continuous charge current ‹ Charge current monitor output for microcontroller or ADC interface ‹ Input voltage range from 4.3V to 14V ‹ 0.1μA battery drain current in shutdown and monitor modes ‹ Operates without a battery in regulated LDO mode ‹ Small 4mm x 4mm 16 lead MLP package ‹ NTC thermistor sense input ‹ Adjustable 6 Hour programmable charge timer ‹ Over current protection in all charging modes ‹ Over voltage protection ‹ Remote Kelvin sensing at the battery terminals ‹ ADC input control capable ‹ Status output communicates charging and end of charge cycle ‹ Charges Li-Ion, Li-Polymer, NiCd and NiMH Batteries ‹ Cellular phones ‹ PDA’s ‹ Handheld meters ‹ Charging stations ‹ Handheld computers ‹ Digital cameras ‹ Programmable current source The SC802 is a fully integrated, single cell, constant-cur- rent/constant-voltage Lithium-Ion\\Lithium Polymer bat- tery charger. With an integrated timer and complete charge control algorithm, the SC802 is well suited for stand-alone charger applications. The SC802 contains programmable pre-charge, fast-charge, and termination current settings. The SC802 can be programmed to ter- minate charge based on the output current or the time- out of the programmable timer. The fast charge current is typically set with an external resistor but can be modi- fied with the analog fast charge input to allow a Power Management Controller to control the fastcharge current setting via DAC. The 14V input voltage range of the SC802 eliminates additional protection circuitry required by other 5V charg- ers in the event of faulty adapters. Reference ground and battery sense inputs are provided to allow Kelvin connections to eliminate IR voltage drops during charging. The output voltage to the battery is controlled to within 1% of the programmed voltage for either 4.1V or 4.2V. The SC802 can also function as a general purpose cur- rent source or as a current source for charging nickel- cadmium (NiCd) and nickel-metal-hydride (NiMH) batter- ies using NTC termination. The SC802A version of the device is optimized for high termination current applications. All descriptions and text refering to the SC802 also apply to the SC802A unless otherwise noted.

Description

t RT1 THERMISTOR CHARGER ADC Iset PRESENT R 1uF SC802 VCC BSEN IPRGM EN/NTC ITERM VOUT RTIM CHRGB VPRGM CPB RFGND BIPB VCC GND VOUT AFC CHARGE 2.2uF BATTERY

2© 2005 Semtech Corp. www.semtech.com SC802/SC802A POWER MANAGEMENT Prelimi- nary * Maximum Vsupply as defined in EIA/JEDEC Standard No. 78, paragraph 2.11. noitanibmoCniPn oitanibmoCniP noitanibmoCniP noitanibmoCniPn oitanibmoCniPl obmySl obmyS lobmyS lobmySl obmySm umixaMm umixaM mumixaM mumixaMm umixaMs tinUs tinU stinU stinUs tinU DNGotNE,CCV 0.41ot3.0-V ,MRETI,BGRHC,BPC,MGRPI,MGRPV,CFA,emitR,TUOV DNGot,BPIB 0.6+ot3.0-V DNGotDNGFER 3.0ot3.0-V noitapissiDrewoP /Wm02etareD(PLM° C 5 8evobaC °) d P2W tneibmAotnoitcnuJ,ecnadepmIlamrehTT AJ *05W /C° esaCotnoitcnuJ,ecnadepmIlamrehTT CJ 3W /C° erutarepmeTnoitcnuJT J 051C ° egnaRerutarepmeTtneibmAgnitarepOT A 58+ot04-C ° s04-s02gniredlos,erutarepmetwolfeRRIkaePT DAEL 062C ° egnaRerutarepmeTegarotST GTS 051ot56-C ° DNGottrohsTUOV suounitnoC Absolute Maximum Ratings

Electrical Characteristics

Unless otherwise noted: VCC = 4.75V - 5.25V * Tied to PCB with 1 Square Inch, 2 Ounce Copper, using JESD 51 Standard. Exceeding the specifications below may result in permanent damage to the device, or device malfunction. Operation outside of th e parameters specified in the Electrical Characteristics section is not implied. retemaraPl obmySs noitidnoC5 2 oCT A 04-( o 58+otC o )C stinU niMp yTx aMn iMx aM egatloVdnatshtiWtupnIC CV3 .44 1V egatloVgnitarepOP OV3 .4* 5.6V dlohserhTgnisiROLVUCCVT V ROLVU 0.47 .33 .4V siseretsyHOLVUCCVT V HOLVU siseretsyHgnillaFCCV0 4V m dlohserhTgnisiRPVOCCVT V RPVO 8.65 .65 .7V dlohserhTgnillaFPVOCCVT V FPVO 5.61 .61 .7V siseretsyHPVOCCVT V HPVO siseretsyHgnillaFCCV0 030 020 05V m tnerruCgnitarepOC CI SID CCI GHC CCI ODL edoMnwodtuhS ffoBPC,BGRHC 6.2 Am edoMgnigrahC ffoBPC,BGRHC 4.21 5 .3 edoMODL ffoBPC,BGRHC 618 3 2

 2005 Semtech Corp. www.semtech.com POWER MANAGEMENT SC802/SC802A Confidential Confidential Proprietary Parameter Symbol Conditions 25oC TA (-40oC to +85 oC) Units Min Typ Max Min Max Battery Leakage Current (Vout and BSEN) ILeakBAT VCC = 0V, VOUT = BSEN = 4.5V 0.1 2 µA Regulated Voltage VBAT2 VBAT1 VPRGM = Logic High VPRGM = Logic Low 4.20 4.10 4.16 4.06 4.24 4.14 V Adjust Mode Feedback Voltage VADJMF VPRGM = External Divider VCC = 4.2V - 6.5V 3.0 V Adj Mode VPRGM Shunt Resistance RVPGMSH Adjust Mode VVPRGM = 0.1V 1 0.5 5 kΩ REFGND Output Accuracy Vout = Voutnom + Drefgnd VREFGND Refgnd - Agnd = 30mV 30 22 38 mV REFGND Current IREFGND Refgnd = 0V 35 µA SC802 Pre-Charge Current IPREQ SC802 Rterm = 3.01kΩ 82 7 4 90 mA SC802 Termination Current ITERMQ SC802 Rterm = 3.01kΩ 42 35.5 49.5 mA SC802 Fast-Charge Current IFastQ IPRGM = 3.01kΩ VBATTERY = 3.8V 500 450 550 mA SC802 AFC DAC Fast-Charge Current IDACADJ IPRGM = 3.01kΩ V(AFC) = 0.75V 240 200 280 mA SC802A Pre-Charge Current IPREQA SC802A Rterm = 976Ω 145 135 160 mA SC802A Termination Current ITERMQA SC802A Rterm = 976Ω 145 135 160 mA SC802A Fast-Charge Current IFastQA IPRGM = 1.78kΩ VBATTERY = 3.8V Rterm = 976Ω 800 7 40 860 mA SC802A AFC DAC Fast- Charge Current IDACADJA IPRGM = 1.78kΩ VAFC = 0.75V VBATTERY = 3.8V Rterm = 976Ω 367 310 430 mA IPROG Regulated Voltage VIPRGM 1.5 1.4 1.6 V Adjust Mode Threshold Voltage VT ADJM Vout - BSEN Voltage 250 50 420 mV VBAT Precharge Threshold VTPreQ 2.8 2.7 2.9 V VBAT Recharge Threshold VTReQ VBAT - VBATTERY 100 70 140 mV Over Temperature Shutdown TPOT Hysteresis = 10°C 150 °C Electrical Characteristics (Cont.) Unless otherwise noted: VCC = 4.75V - 5.25V

 2005 Semtech Corp. www.semtech.com POWER MANAGEMENT SC802/SC802A Confidential Confidential Proprietary Parameter Symbol Conditions 25oC TA (-40oC to +85oC) Units Min Typ Max Min Max EN-NTC Thresholds VTNTCDIS SC802 Disable <1 0.5 1.1 V 28.2 30 31.8 28 32 % 72.4 75 77 .6 72 78 % 84.4 90 91.6 84 92 % VTNTHYS Hot/Cold Vth hysteresis 50 mV Timer Disable Threshold VTTIMER VRTIME < VTTIMER Disables Timer 1 0.7 1.1 V Internal Timer Select VTINTTS VCC-VRTIME < VTINTTS selects internal timer 1.5 V Ext RTIME Voltage VRTIME RTIME tied through 36.5kΩ to GND 1.5 1.4 1.6 V Pre-Charge Fault Time-out TPreQF RTIME tied through 36.5kΩ to GND RTIME tied to VCC 45 -35% +35% min Complete Charge Time-out TQCOMP RTIME tied through 36.5kΩ to GND RTIME tied to VCC 3.3 3 -35% +35% hr CHRGB Charge LED On VCHRGB Load = 5mA 0.5 1 V CHRGB Charge LED Off ICHRGB Leakage Current, V = 5V 1 µA CPB LED On VCPB Load = 5mA 0.5 1 V CPB LED Off ICPB Leakage Current, V = 5V 1 µA BIPB, VPRGM Inputs VIH 1.8 V VIL 0.4 V Unless otherwise noted: VCC = 4.75V - 5.25V Electrical Characteristics (Cont.)

5© 2005 Semtech Corp. www.semtech.com SC802/SC802A POWER MANAGEMENT PRELIMINARYPin Configuration Ordering Information Pin Descriptions #niPe maNniPn oitcnuFniP 1N ESB evaeltonoD.egatlovyrettabesnesnivleKotlanimretyrettabottcennoC.nipesnesegatlovyrettaB .gnitaolfnipsiht 3M GRPI -tsafmargorpotdnuorgotrotsiseraseriuqeR.edomegrahctsafninipmargorptnerrucregrahC .tnerrucegrahc 4M RETI margorpotdnuorgotrotsiseraseriuqeR.tnerrucegrahc-erpdnanoitanimrettnerrucrofnoitceleS .tnerrucnoitanimretdnaegrahc-erp 5D NGFER .lanimretevitagenyrettabotnoitcennocnivleKswollA.dnuorGecnerefeR 6D NGd nuorG 7C TN-NE wolcigoL.ecivedselbanehgihcigoL.niptupniCTNdnaelbasid/elbaneeciveDdenibmoC .noitcnufCTNehtelbaneCCV57.0dnaCCV3.0neewtebsegatlovgolanA.ecivedselbasid BPIB .edomegrahcstceleswoL=BPIB.edomODL/egrahCstceles)BPIB(raBecalPniyrettaB snoitcnuftuo-remitdnaegrahC-erPselbasidhcihwedomODLstceleshgiH=BPIB 9C FA .eulavtnerrucegrahctsaffolortnocgolanarofCADottcennoC.gnitteSegrahCtsaFgolanA .nepoevaeltonoD.CFAelbasidotCCVottcennoC 01B GRHC tuptuoehtdnanosiregrahCehtnehwwolevitcasituptuoehT.niPsutatSregrahCniarDnepO hgihotsehctiwstuptuoehT.eulavtnerrucnoitanimretehtsdeecxetnerruc .Am01knisnacnipsihT.noitanimretI<tuoInehwecnadepmi 11B PC sihT.OLVUsdeecxeCCVehtnehwwolevitcasituptuoehT.rotacidnitneserpregrahCniarDnepO .Am01knisnacnip ECIVED )1( EGAKCAP RTLMI208CS6 1-PLM TRTLMI208CS )2( 61-PLM TRTLMIA208CS )2( 61-PLM BVE208CS )3( draoBnoitaulavE Note: (1) Only available in tape and reel packaging. A reel contains 3,000 devices. (2) TRT extension designates the lead-free leadframe package option. This product is fully WEEE and RoHS compliant. (3) Specify the desired IC part number when ordering. (MLP-16 Lead: 4x4) Top View

6© 2005 Semtech Corp. www.semtech.com SC802/SC802A POWER MANAGEMENT Prelimi- nary Block Diagram VOUT Refe re nce Voltages 4.2V 4.1V Fast Charge Ref Pre-Charge Ref Fast Charge Ref Pre-Charge Ref Vp r o g Mode Detect2 Vo ut Programmable Timer NT C Interface7 Control BSEN AFC EN-NTC RTIM CP B CHRGB REFGND VP RGM GND GND VCC IP RGM ITERM BIPB Pre-Charge On Fast-Charge On Over Voltage Under Voltage Over Temp Charge/LDO On VOUT Refe re nce Voltages 4.2V 4.1V Fast Charge Ref Pre-Charge Ref Fast Charge Ref Pre-Charge Ref Vp r o g Mode Detect2 Vo ut Programmable Timer NT C Interface7 Programmable Timer NT C Interface7 ControlControl BSEN AFC EN-NTC RTIM CP B CHRGB REFGND VP RGM GND GND VCC IP RGM ITERM BIPB Pre-Charge On Fast-Charge On Over Voltage Under Voltage Over Temp Charge/LDO On #niPe maNniPn oitcnuFniP 21E MITR ottcennoc,srh3fotuo-emitlanretniehttcelesotCCVottcennoC.niptupniremitelbamargorP .doireptuoemitehtmargorpotdnuorgotrotsiserlanretxenatcennoC.remitehtelbasidotdnuorg 31C CV. rewoprotpadaottcennoc,nipylppuS 41C CV. rewoprotpadaottcennoc,nipylppuS 51T UOV. yrettabottcennoc,tuptuoregrahC 61T UOV. yrettabottcennoc,tuptuoregrahC Tl amrehT daP detcennoctoN.saivelpitlumgnisuenalpdnuorgottcennoC.sesoprupgniknistaehrofdaP .yllanretni Pin Descriptions (Cont.)

7© 2005 Semtech Corp. www.semtech.com SC802/SC802A POWER MANAGEMENT PRELIMINARY ceeds 1/4 of the total charge cycle the charger will turn off due to a pre-charge fault. This fault is cleared when EN or VCC is toggled or the output voltage rises above 2.8V. Fast-Charge Mode (CC) The fast-charge or CC mode is active when the battery voltage is above 2.8V and less than the CV or final float charge voltage of the battery. The fast-charge current can be set to a maximum of 1.0A and is selected by the program resistor on the IPRGM pin. The voltage on this pin will represent the current through the battery enabling a microprocessor via an analog-to-digital converter (ADC) to monitor battery current by sensing the voltage on the IPRGM pin. The equation to set the fast-charge current is given by: Note that for a given program resistor the current through the battery in CV mode can be determined by replacing 1.5 with the actual voltage on the IPRGM pin in the above equation. The CC current can also be modified by apply- ing an analog voltage to the AFC pin as described below. Analog Fast Charge (AFC Pin) Many applications require more than one current setting for Fast Charge. This feature is included in the SC802 by using the AFC function. When the AFC pin is con- nected to VCC the device behaves as described in the previous section. When the AFC pin is driven by and analog voltage between 0 and 1.5V the SC802 auto- matically uses this pin voltage to set the maximum fast- charge current setting according to the following equa- tion. General Operation The SC802 is configured based on the application for Fast Charge and Termination current, output voltage, tim- ing requirements, and operation with and without a bat- tery (ldo mode). A typical charging cycle is described be- low. Details on alternate applications and output pro- grammability are covered in the individual sections. The charging cycle begins when the adapter is plugged in. The SC802 performs glitch filtering on the VCC input and initiates a charge cycle when VCC > UVLO. At this time, the CPB and CHRGB signals are active turning on the charger LED’s. If the battery voltage is less than 2.8V, the SC802 will charge the output with the pre- charge current. When the battery voltage exceeds 2.8V, the SC802 enters fast-charge or constant current (CC) mode. When the battery voltage reaches its final value, the charger enters the constant voltage (CV) mode. In this mode the output current decreases as the battery continues to charge until the termination current level is reached. The CHRGB led turns off when Iout is less than Itermination but the SC802 continues to hold the bat- tery in CV charge mode until the timer expires. At this point the charger enters the monitor mode where the output remains off until Vout drops by 100mV and a new charge cycle is initiated. Pre-Charge Mode Pre-charge mode is automatically enabled whenever the battery voltage is below 2.8V. It is used to limit the power dissipation and precondition the battery for fast charg- ing. The pre-charge current value is selected by the re- sistor on the ITERM pin. The pre-charge current is pro- grammable from 10mA to 125mA on the SC802 and up to 150mA on the SC802A. The equation to select the pre-charge current is different for the two part types and given by: If the charge timer is in use there is also a maximum allowed pre-charge duration. If the pre-charge time ex- Applications Information 1000 R 1.5FCI :SC802 PRGM ×⎟⎟ Iterm0.3-1000 R 1.5FCI :SC802A PRGM ××⎟⎟ 88 R 2.8PCI :SC802 TERM ×⎟⎟ 97 R 1.5PCI :SC802A TERM ×⎟⎟ 1000 R VAFCI :SC802 PROG AFC ×⎟⎟ Iterm0.3-1000 R VAFCI :SC802A PROG AFC ××⎟⎟

8© 2005 Semtech Corp. www.semtech.com SC802/SC802A POWER MANAGEMENT Prelimi- nary Charge Timer The timer on the SC802 is used as protection in the case of a faulty battery and to maximize charging capacity. Tie the RTIM pin to VCC to select the internal timer, GND to disable the timer. Connecting a resistor between RTIM and GND will program the total charge time according to the following equation with the charge time expressed in hours. Ω×= 12.5k Time Q Total RTIM The timer is programmable over the range of 2 to 6hrs. The internal timer selection results in a charge time of 3hrs. The CHRGB blink rate in fault condtions is a func- tion of the timer setting when an external RTIM is used. The SC802 will automatically turn off the output when the charge timer times out. LDO Mode The SC802 is designed to work with or without a battery. If the battery is not in place the device can enter the LDO mode. In this mode the SC802 will act like a low dropout regulator. The output voltage is set to 4.1V, 4.2V or externally set by a resistor divider. See the section titled “Configuring the output voltage to the battery” for setting an output voltage. The input pin BIPB (Battery In Place Bar) is used to switch the SC802 from charger mode to LDO mode. If this pin is logic high the device will be in LDO mode, if it is logic low it will be in the charger mode. During LDO mode the device will regulate the out- put voltage with a current limit set by the resistor tied to the IPRGM pin. The BIPB pin should never be left float- ing. It should be tied through pull-up/pull-down resistors when connected to a high impedance control pin or it can be connected directly to the VCC pin or GND. EN-NTC Interface The Enable pin on the SC802 provides two functions. It can be used to turn on/off the device by driving it to VCC/Ground. It can also be connected to an external resistor divider consisting of a resistor and an NTC Ther- mistor to disable the charge cycle when the temperature is out of range. This configuration is shown in the typical application schematic on page 1 of the datasheet. When the NTC voltage from the divider is above or below the hot and cold temperature threshold values the SC802 will suspend the charge cycle by turning off the output, freezing the charge timer, and indicating a fault on the CHRGB LED. Hysteresis is included for both thresholds to avoid chatter at the NTC trip points. When the tem- Applications Information Cont. Termination Current Once the battery reaches the program voltage of 4.1V, 4.2V or externally set voltage, the device will transition from a constant current source to a constant voltage source. The current through the battery begins to de- crease while the voltage remains constan until it falls below the programmed termination current set by the termination resistor on the ITERM pin. The SC802 will turn off the CHRGB Led. If the timer is enabled the out- put will continue to float charge in CV mode until the timer expires. If the timer is disabled than the output will turn off as soon as the termination current level is reached. The equation for setting the the termination current The termination current is programmable up to 67mA for the SC802. The termination current is programmable up to 150mA with VCC=5V on the SC802A. Monitor Mode When a charge cycle is completed, the SC802 output turns off and the device enters monitor mode. If the voltage of the battery falls below the recharge threshold of CV-100mV the charger will clear the charge timer and re-initiate a charge cycle. The maximum current drain of the battery during monitor mode will be no more than 1uA over temperature. The status of the charger output as a function of BIPB, Timer, and IOUT is shown below. tuptuO etatS BPIBr emiTt uoI nO hgiHA /NA /N nO woLr emiT<TA /N ffO woLr emiT>TA /N ffO woLd elbasiDn oitanimretI< 88 R 1.5ITERM :SC802 TERM ×⎟⎟ 97 R 1.5ITERM :SC802A TERM ×⎟⎟

9© 2005 Semtech Corp. www.semtech.com SC802/SC802A POWER MANAGEMENT PRELIMINARY Applications Information Cont. perature returns to the valid range the SC802 automati- cally resumes the charge cycle. The charge timer will time-out when the SC802 output on-time exceeds the timer setting regardles of how long it has been disabled due to temperature. The internal NTC thresholds of 30% and 75% VCC were designed to work with curve-2 type thermistors available from numerous vendors. Design Example based on the typical application sche- matic of page 1 using a Curve 2 Vishay-Dale NTC. Thot = 50 oC Tcold = 0oC Find R3 and RT1 Step 1: Pick an RT1 value high enough to prevent self- heating. DC V(RT1) RT1 In general lower values of RT1 provide more noise for the NTC voltage at the expense of bias current from the input adapter. The dissipation constant DC is the power rating of the NTC resulting in a 1 oC self heating error. The DC value for this NTC is 3mW and the voltage across the NTC is 2.5V for a 5V adapter. Therefore RT1 > 2k. Set RT1 = 10k Step 2: Find R3 to set the correct Hot level trip point 9.52k R R R 2.33R3 T25 T50 T25 =⎟⎟ ⎛××= The closest standard resistor value is 9.53k. RT(temp)/ RT(25oC) is often referred to as the ratio at the given temp. For this NTC at 50 oC the ratio is 0.4086. Step 3: Calculate the Tcold value. 2.86 10k R3 3RT RT COLD =⎟ ⎛×=⎟⎟ The ratio for the Curve 2 NTC at 0 o is 2.816. The differ- ence represents less than 1/2 oC (ie actual trip would be -0.5oC instead of 0oC.) For temperature trip values other than 0 oC and 50 oC alternate curve-type NTC elements can be used or an additional resistor can be added to the Rntc divider to alter the temperture coefficient. LED Flags There are two LED drivers on the SC802: CHRGB (Charge) and CPB (Charger Present). These outputs are open drain NMOS drivers for controlling LEDs directly. The Table be- low defines each LED output state. DEL GALF NOF FOg niknilB BPC OLVU <CCV< PVO rewoP dooGtoN X BGRHC >tuoI mretI <tuoI *mretI egrahCerP CTNro tluaF * Output remains on when timer is enabled and t < timeout The CPB output can be used for a VCC indicator. Re- gardless of the state of EN, the CPB output reflects the voltage of the VCC (adapter) input. When VCC is between the UVLO and OVP thresholds the CPB output is low. The CHRGB output signifies the charging status. When the output current is > Itermination, CHRGB=low. CHRGB is high when Iout is < Itermination. The CHRGB output is latched during the charge cycle when the output current is less than Itermination. This latch is reset when the battery enters a re-charge cycle, or if BIPB, EN, or VCC are toggled. The CHRGB indicator operates the same way in both charge and ldo mode. There are five fault modes detected by the SC802; (In- put under voltage, input over voltage, NTC temperature, Max die temperature or OT and pre-charge timeout) The LED states for these fault modes are shown below. tluaFB PCB GRHC OLVUCCV ro PVOCCV ffof fo tluaFCTN nog niknilB egrahC-erP tuo-emiT nog niknilB C051>jT ffof fo

10© 2005 Semtech Corp. www.semtech.com SC802/SC802A POWER MANAGEMENT Prelimi- nary Configuring the Output Voltage to the Battery Fixed Mode The battery voltage is set by the VPRGM pin in fixed mode and externally in adjust mode. If VPRGM is logic high the output voltage is set to 4.2V. If this pin is logic low the output voltage will be set to 4.1V. For a value other than 4.1V or 4.2V a resistor divider is required. Adjust Mode When the SC802 is configured with an output voltage other than 4.1 or 4.2V it is operating in adjust mode. In adjust mode the output voltage is set by an external re- sistor divider. The SC802 provides the ability to discon- nect the external feedback resistor divider when the battery is not being charged to reduce current drain from the battery in normal operation. Connect the external resistor divider between the VOUT pin and the VPRGM pin with the divider tap connected to the BSEN pin to utilize this feature. The SC802 adjust mode schematic is shown above. The equation for setting the output voltage is: 3.0 R3 R41VOUT ×⎟ ⎛ += The capacitor across R4 in the feedback networks intro- duces zero-pole frequency compensation for stability. Place the zero according to the following equation to in- sure stability. kHz1002 1C1R4 ×=× π When the SC802 is in Adjust mode the VCC is required to be 150mV > Vout. Internal protection circuits will dis- able the output if VOUT approaches VCC. t RT1 THERMISTOR 1uF CHARGER VIN ADC Iset Adjust Mode Schematic 2.2uF SC802 VCC BSEN IPRGM EN/NTC ITERM VOUT RTIM CHRGB VPRGM CPB RFGND BIPB VCC GND VOUT AFC CHARGER BATTERY PRESENTCHARGE Capacitor Selection Input and output capacitors can be low cost ceramic type. The output capacitance range is 1uF to 4.7uF. The input capacitor is typically between 0.1uF to 1uF but larger values will not degrade performance. Overcurrent and Max Temperature Protection Overcurrent protection is inherent in all modes of opera- tion. When the device is in charge-mode (BIPB=low) the output is current limited to either the pre-charge current limit value or the fast charge current limit value depend- ing on the voltage at the output. When the device is in LDO mode (BIPB=high) the output current is limited to the fast charge current limit. Max die temperature pro- tection is included on the SC802. This feature allows the SC802 to operate with maximum power dissipation by disabling the output current when the die tempera- ture reaches OT. The result is that the SC802 will oper- ate as a pulse charger in extreme power dissipation ap- plications delivering the maximum allowable output cur- rent while regulating the internal die temperature to a safe level. Remote Kelvin Sensing at the Battery Kelvin sensing of both the positive and negative termi- nals of the battery is possible with the SC802. The BSEN pin provides the positive sensing voltage feedback to the CV amplifier and should be connected as close to the battery + terminal as possible. Likewise the REFGND pin should be kelvin connected to the negative terminal of the battery. This allows the designer great flexibility in PCB layout and achieves a much greater accuracy in sens- ing the battery voltage where it counts, at the battery terminals! Therefore, when laying out the PCB the de- signer should route the BSEN pin directly to the terminal at which the battery gets connected. In the LDO mode, the BSEN pin will still need to sense the output voltage;

11© 2005 Semtech Corp. www.semtech.com SC802/SC802A POWER MANAGEMENT PRELIMINARY State Diagram Shutdown Mode Vout/Iout off CHRGB High Z CPB Low Soft Start CC Mode Start Pre-Charge Yes OVP> Vin > UVLO Iout=1500/Rprog SC802:Iout=246/Rterm SC802A:Iout=145/Rterm Over Voltage, Under Voltage, or Over Temperature will force the SC802 into Shutdown Mode from any state. Monitor Mode Vout=off Float Charge Mode Vout = CV Yes Soft Start Vout Yes En=Hi BIPB=Low Timer Enabled? Start Timer Vout>2.8V Time>Tmax/4 Iout<Iterm Vout=CV Start CV Mode CHRGB Low CHRGB High Z Vout< CV-100mV Pre-Charge Timeout Fault CHRGB blinks at 0.5Hz Cleared by Vbat>2.8V or Re-cycle EN or VCC NTC out of Range Fault CHRGB blinks at 0.5Hz Timer is frozen Charge resumes when NTC Temperature is valid 0C > NTC Temp >50C CC=Constant Current CV=Constant Voltage Yes Yes Yes Yes Yes Yes Yes Start LDO Mode Iout<Iterm CHRGB High Z Float Charge Mode Vout = CV Time>Tmax Timer Enabled? Time>Tmax Vout< CV-100mV Yes Yes Yes Shutdown Mode Vout/Iout off CHRGB High Z CPB Low Soft Start CC Mode Start Pre-Charge Yes OVP> Vin > UVLO Iout=1500/Rprog SC802:Iout=246/Rterm SC802A:Iout=145/Rterm Over Voltage, Under Voltage, or Over Temperature will force the SC802 into Shutdown Mode from any state. Monitor Mode Vout=off Float Charge Mode Vout = CV Yes Soft Start Vout Yes En=Hi BIPB=Low Timer Enabled? Start Timer Vout>2.8V Time>Tmax/4 Iout<Iterm Vout=CV Start CV Mode CHRGB Low CHRGB High Z Vout< CV-100mV Pre-Charge Timeout Fault CHRGB blinks at 0.5Hz Cleared by Vbat>2.8V or Re-cycle EN or VCC NTC out of Range Fault CHRGB blinks at 0.5Hz Timer is frozen Charge resumes when NTC Temperature is valid 0C > NTC Temp >50C CC=Constant Current CV=Constant Voltage Yes Yes Yes Yes Yes Yes Yes Start LDO Mode Iout<Iterm CHRGB High Z Float Charge Mode Vout = CV Time>Tmax Timer Enabled? Time>Tmax Vout< CV-100mV Yes Yes Yes

12© 2005 Semtech Corp. www.semtech.com SC802/SC802A POWER MANAGEMENT Prelimi- nary Evaluation Board Schematic 1uF TP1 CHARGER+ JP1 4.2V TP7 ISENSE 100K SC802 16BSEN VPRGM IPRGM ITERM RFGND GND EN-NTC BIPB RTIM CHRGB CPB AFC VCC VCC VOUT VOUT TP5 GND CHRG JP4 4.1V TP8 RGND TP4 VOUT JP2 TINT 1 2 No Pop 3.01K 37.5K TP3 EN-NTC CP TP2 CHARGER- No Pop 2.2uF 10K JP3 LDO 1 2 No Pop TP6 AFC Marking Information 802 yyww Top view. Marking for the SC802 MLP 16 Lead package: yyww = Date Code (Example: 0012) 802A yyww

13© 2005 Semtech Corp. www.semtech.com SC802/SC802A POWER MANAGEMENT PRELIMINARY Typical Characteristics Battery Charge Profile 3.2 3.4 3.6 3.8 4.2 4.4 0:00:00 0:12:30 0:25:00 0:37:30 0:50:00 1:02:30 1:15:00 1:27:30 1:40:00 1:52:30 2:05:00 2:17:30 2:30:00 2:42:30 2:55:00 3:07:30 3:20:00 3:32:30 3:45:00 TIME VOLTAGE (Volts) 0.1 0.2 0.3 0.4 0.5 0.6 CURRENT (Amps) V CHARGE V CHRGB I CHARGE Output Current -vs- Rprgm 0.5 1.5 0.75 1.5 2.5 3.5 4.5 5.5 6.5 Resistance (Kohm) Current (A) Fast Charge Drop-out Voltage -vs- Output Current 100 200 300 400 500 600 700 1000 800 600 500 450 300 250 200 100 Output Current (mA) Dropout Voltage (mV) V dropout Time-Out -vs Rtime 10 20 40 60 80 R esistance (K ohm) Time-out (hrs) Pre-Charge Timeout Fast Charge Timeout SC802 (non-A) Output Current -vs- Rterm 100 150 200 250 Resistance (Kohm) Current (A) SC802 Pre-Charge SC802 Termination

14© 2005 Semtech Corp. www.semtech.com SC802/SC802A POWER MANAGEMENT Prelimi- nary Charge Mode Timing Diagram LDO Mode Timing Diagram CHRGB VCC NTC IOUT VOUT CPB TIMER (Disabled) UVLO Soft Start 2.8V CC-mode Fast Charge CV-mode Off On On Off Termination Current Re-Charge Threshold Fault LDO-Mode Timing Load Current Transient CHRGB VCC NTC IOUT VOUT CPB TIMER Pre-Charge UVLO Soft Start 2.8V CC-mode On Fast Charge CV-mode On On Hold Off On On Off Termination Current Re-Charge Threshold Fault Charge Mode Timing

15© 2005 Semtech Corp. www.semtech.com SC802/SC802A POWER MANAGEMENT PRELIMINARY .003 .010 .079 .012 .085 .000 .031 (.008) 0.08 0.30 .014 .089 0.25 2.00 .040 .002 0.00 0.80 2.25 0.35 2.15 0.05 1.00 (0.20) .004 0.10 2.00 2.15 2.25 0.65 BSC.026 BSC .089.085.079 D/2 A LxN bbb C A B bxN e SEATING PLANE C E/2 N e/2 aaa C CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). COPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS THE TERMINALS. NOTES: A D E B INDICATOR (LASER MARK) PIN 1 DIMENSIONS NOM INCHES N bbb aaa DIM L e E D A b MIN MAX MILLIMETERS MINMAX NOM Outline Drawing - MLP-16 (4 x 4 x 0.9mm)

16© 2005 Semtech Corp. www.semtech.com SC802/SC802A POWER MANAGEMENT Prelimi- nary Semtech Corporation Power Management Products Division

200 Flynn Road, Camarillo, CA 93012

Phone: (805)498-2111 FAX (805)498-3804 Contact Information Land Pattern - MLP-16 (4 x 4 x 0.9mm) THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ARE MET. NOTES: 2x GH2x (C) 2x Z X P Y K C Z P Y X G K H .189 .026 .016 .037 .114 .091 .091 4.80 0.40 0.95 0.65 2.30 2.30 2.90 DIM (3.85) MILLIMETERS DIMENSIONS (.152) INCHES