MP2633A 1.5A Single Cell Switch Mode Battery Charger with Power Path Management and Boost OTG The Future of Analog IC Technology DESCRIPTION FEATURES The MP2633A is a highly-integrated, flexible, switch-mode battery charge management and system power path management device for a single-cell Li-ion and Li-Polymer battery used in a wide range of portable applications. The MP2633A has two operating modes— charge mode and boost mode—to allow management of system and battery power based on the state of the input. When input power is present, the device operates in charge mode. It automatically detects the battery voltage and charges the battery in the three phases: trickle current, constant current and constant voltage. Other features include charge termination and autorecharge. This device also integrates input current limit in order to manage input power and meet the priority of the system power demand. . In the absence of an input source, the MP2633A switches to boost mode through the MODE pin to power the SYS pins from the battery. The OLIM pin programs the output current limit in boost mode. The MP2633A also allows an output short-circuit thanks to an output disconnect feature, and can auto-recover when the short circuit fault is removed. The MP2633A provides full operating status indication to distinguish charge mode from boost mode. 4.5V-to-6V Operating Input Voltage Range Integrated Input-Current-Based Power Management Function Up to 1.5A Programmable Charge Current Trickle-Charge Function Selectable 3.6V/ 4.2V Charge Voltage with 0.5% Accuracy Negative Temperature Coefficient Pin for Battery Temperature Monitoring Programmable Timer Back-Up Protection Thermal Regulation and Thermal Shutdown Internal Battery Reverse Leakage Blocking Reverse Boost Operation Mode for System Power Up to 91% 5V Boost Mode Efficiency @ 1A Programmable Output Current Limit for Boost Mode Integrated Short Circuit Protection for Boost Mode APPLICATIONS Sub-Battery Applications Power-Bank Applications for Smart-Phone, Tablet and other Portable Device All MPS parts are lead-free and adhere to the RoHS directive. For MPS green status, please visit MPS website under Products, Quality Assurance page. “MPS” and “The Future of Analog IC Technology” are registered trademarks of Monolithic Power Systems, Inc. The MP2633A achieves low EMI/EMC performance with well-controlled switching edges. To guarantee safe operation, the MP2633A limits the die temperature to a preset value 120oC. Other safety features include input overvoltage protection, battery over-voltage protection, thermal shutdown, battery temperature monitoring, and a programmable timer to prevent prolonged charging of a dead battery. MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 1 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER TYPICAL APPLICATION To 5V System R1 R2 R OLIM C2 FB SYS 5V Input C SYS OLIM IN L1 SW RS1 I CHG I BATT R4 C IN C1 R3 C3 CSP REG BATT R5 NTC MP2633A CHG ACOK FREQ BOOST EN VCC ISET MODE ILIM Battery Voltage GND: 3.6V Programmable Pin High/Float: 4.2V VB VCC C4 Battery VSYS PWIN R6 CBATT VBATT AGND TMR PGND RILIM CTMR R ISET Table 1: Operation Mode Power Source __________ ACOK EN High MODE Charge Mode, Enable Charging 0.8V<PWIN<1.15V & VIN>VBATT+300mV Low PWIN<0.8V or PWIN >1.15V or VIN<VBATT+300mV High X High Boost Mode VIN<2V High X Low Sleep Mode Low X Operating Mode Charge Mode, Disable Charging X=Don’t Care. MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 2 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER ORDERING INFORMATION Part Number* MP2633AGR Package QFN24 (4×4mm) Top Marking MP2633 * For Tape & Reel, add suffix –Z (e.g. MP2633AGR–Z); PACKAGE REFERENCE TOP VIEW EN MODE S YS S YS SW PG ND 24 23 22 21 20 19 FREQ 1 18 CHG VIN 2 17 BOOST VCC 3 16 CSP ILIM 4 15 BATT PWIN 5 14 VB TMR 6 13 AGND 9 10 REG ACOK FB NTC 11 12 OLIM 8 ISET 7 EXPOSED PAD ON BACKSIDE ABSOLUTE MAXIMUM RATINGS (1) Thermal Resistance VIN ................................................. –0.3V to 20V SYS, SW ....................................... –0.3V to 6.5V BATT ............................................. –0.3V to 6.5V QFN24 (4×4mm)..................... 42 ........9 ... °C/W ----------------- ------------- --------------------- ACOK, CHG, BOOST ................... –0.3V to 6.5V All Other Pins ................................ –0.3V to 6.5V Junction Temperature ...............................150°C Lead Temperature ....................................260°C (2) Continuous Power Dissipation (TA = +25°C) ........................................................... 2.97W Junction Temperature ...............................150°C Operating Temperature............. –20°C to +85°C Recommended Operating Conditions (3) (4) θJA θJC Notes: 1) Exceeding these ratings may damage the device. 2) The maximum allowable power dissipation is a function of the maximum junction temperature TJ (MAX), the junction-toambient thermal resistance θJA, and the ambient temperature TA. The maximum allowable continuous power dissipation at any ambient temperature is calculated by PD (MAX) = (TJ (MAX)-TA)/θJA. Exceeding the maximum allowable power dissipation will cause excessive die temperature, and the regulator will go into thermal shutdown. Internal thermal shutdown circuitry protects the device from permanent damage. 3) The device is not guaranteed to function outside of its operating conditions. 4) Measured on JESD51-7, 4-layer PCB. Supply Voltage VIN ............................ 4.5V to 6V Battery Voltage VOUT ..................... 2.5V to 4.35V Operating Junction Temp. (TJ). −40°C to +125°C MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 3 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER ELECTRICAL CHARACTERISTICS VIN = 5.0V, TA = 25°C, unless otherwise noted. Parameter Symbol Condition IN to SYS NMOS ON Resistance High-side PMOS ON Resistance Low-side NMOS ON Resistance RIN to SYS RH DS RL DS High-Side PMOS Peak Current Limit IPEAK_HS Low-Side NMOS Peak Current Limit IPEAK_LS Switching Frequency VCC UVLO VCC UVLO Hysteresis PWIN, Lower Threshold Lower Threshold Hysteresis PWIN, Upper Threshold Upper Threshold Hysteresis Charge Mode Input Quiescent Current CC Charge Mode/Boost Mode TC Charge Mode FREQ = 0 FREQ = Float/ High fSW VCC Min 2 UVLO VPWIN L 0.75 VPWIN H 1.1 IIN EN = 5V, Battery Float EN = 0 RlLIM = 90.9k RlLIM = 49.9k RlLIM = 20k Max Units 100 72 70 mΩ mΩ mΩ 3 A 1.5 A 2.5 A 600 1200 2.2 100 0.8 40 1.15 65 kHz 2.4 0.85 1.2 2.5 1.5 500 900 2200 V mV V mV V mV mA mA Input Current Limit IIN_LIMIT Input Over-Current Threshold Input Over-Current Blanking Time(5) Input Over-Current Recovery Time(5) IIN(OCP) 450 810 2000 3 τINOCBLK 120 µs τINRECVR 100 ms Terminal Battery Voltage Recharge Threshold VBATT_FULL VRECH Connect VB to GND Leave VB floating or connect to logic HIGH Connect to VB to GND Leave VB floating or connect to logic HIGH 400 720 1800 Typ Constant Charge (CC) Current ICC RS1 = 40mΩ, RISET = 69.8k RS1 = 40mΩ, RISET = 46.4k A 3.582 3.6 3.618 4.179 4.2 4.221 3.35 3.4 3.45 3.91 3.96 4.01 900 1350 200 103.3% 1000 1500 Recharge Threshold Hysteresis Battery Over Voltage Threshold mA V V mV VBATT 1100 1650 MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. FULL mA 4 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER ELECTRICAL CHARACTERISTICS VIN = 5.0V, TA = 25°C, unless otherwise noted. Parameter Trickle-Charge Current Trickle-Charge Voltage Threshold Trickle-Charge Hysteresis Termination Charge Current Input-Voltage-Regulation Reference Boost Mode SYS Voltage Range Feedback Voltage Feedback Input Current Boost SYS Over-Voltage Protection Threshold Symbol ITC VBATT_TC IBF Condition Min Connect to VB to GND Leave VB floating or connect to high logic RISET = 70K VREG VSYS(OVP) VFB=1V Threshold over VSYS to turn off the converter during boost mode 2.47 Typ 10% 2.57 Max Units ICC 2.67 2.9 3 3.1 5% 60 10% 15% mV ICC 1.18 1.2 1.22 V 4.2 1.18 1.2 6 1.22 200 V V nA 5.8 6 6.2 V V SYS Over-Voltage Protection Threshold Hysteresis Boost Quiescent Current Programmable Boost Output Current Limit Accuracy Programmable Boost Output Current(5) SYS Over-Current Blanking Time(5) SYS Over-Current Recovery Time(5) τSYSOCBLK 120 µs τSYSRECVR 500 µs Weak-Battery Threshold VBATT(LOW) VSYS falling from VSYS(OVP) 125 ISYS = 0, MODE = 5V IOLIM RS1 = 40mΩ, ROLIM = 69.8k 0.9 RS1 = 50mΩ, ROLIM=56k 1 1 mV 1.4 mA 1.1 A A During Boost mode Before Boost mode 2.5 2.9 3.05 V V VBATT = 4.2V, SYS Float, VIN = 0V, MODE = 0V 15 30 μA 400 mV 1 μA Sleep Mode Battery Leakage Current ILEAKAGE Indication and Logic ---------------- ------------ ------------------- ACOK, CHG, BOOST pin output low voltage ---------------- ------------ Sinking 1.5mA ------------------- ACOK, CHG, BOOST pin leakage current NTC and Time-Out Fault Blinking Frequency(5) EN Input Logic LOW Voltage EN Input High Voltage Mode Input Logic LOW Voltage Mode Input Logic HIGH Voltage Connected to 5V CTMR=0.1μF, ICHG=1A 13.7 Hz 0.4 1.4 0.4 1.4 MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. V V V V 5 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER ELECTRICAL CHARACTERISTICS VIN = 5.0V, TA = 25°C, unless otherwise noted. Parameter Protection Trickle-Charge Time Total Charge Time NTC Low Temp, Rising Threshold NTC Low Temp, Rising Threshold Hysteresis NTC High Temp, Rising Threshold NTC High Temp, Rising Threshold Hysteresis Charging Current Fold-back Threshold(5) Thermal Shutdown Threshold(5) Symbol Condition Min CTMR=0.1µF, remains in TC mode, ICHG= 1A CTMR=0.1µF, ICHG= 1A 65% Typ Max Units 60 Min 360 Min 66% 67% RNTC=NCP18XH103(0°C) 1% VSYS 34% 35% 36% RNTC=NCP18XH103(50°C) 1% Charge Mode 120 °C 150 °C Notes: 5) Guaranteed by design. MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 6 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER TYPICAL CHARACTERISTICS CIN=CBATT=CSYS=C3=22µF, C1=C2=1µF, L1=4.7µH, RS1=50mΩ, C4=CTMR=0.1µF, Battery Simulator, unless otherwise noted. 2 1.6 1.00 1.5 1.2 0.00 1 0.8 -1.00 0.5 0.4 -2.00 0 0 40 80 120 160 0 60 80 100 120 -3.00 140 4 4.5 5 5.5 6 1200 6 BATT=Float 1000 5.6 800 5.2 600 4.8 400 4.4 200 0 4 4 4.5 5 5.5 6 0 0.5 1 1.5 1.2 5.00 1.2 1 3.00 0.8 0.9 1.5 2 2.5 1.00 0.6 0.6 0.3 0 40 -1.00 0.4 -3.00 0.2 70 100 130 160 190 220 0 80 100 120 140 -5.00 3 3.4 3.8 MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 4.2 7 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER TYPICAL PERFORMANCE CHARACTERISTICS VIN=5V, CIN=CBATT=CSYS=C3=22µF, C1=C2=1µF, L1=2.2µH, RS1=50mΩ, C4=CTMR=0.1µF, Battery Simulator, unless otherwise noted. CHGOK 2V/div. VBATT 100mV/div. CHGOK 2V/div. VBATT 1V/div. VIN 1V/div. ICHG 1A/div. VSW 2V/div. CHGOK 5V/div. VBATT 200mV/div. IL 200mA/div. VIN 1V/div. ICHG 1A/div. VSW 2V/div. VSW 2V/div. VSW 2V/div. VIN 1V/div. VBATT 2V/div. IL 500mA/div. VIN 1V/div. VBATT 2V/div. IL 1A/div. VIN 1V/div. VBATT 2V/div. IL 1A/div. 100 100 90 95 80 90 70 85 60 50 0 1 2 3 4 BATTERY VOLTAGE (V) 5 80 0 0.5 1 1.5 2 CHARGE CURRENT (A) MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 8 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER TYPICAL PERFORMANCE CHARACTERISTICS (continued) VIN=5V, CIN=CBATT=CSYS=C3=22µF, C1=C2=1µF, L1=2.2µH, RS1=50mΩ, C4=CTMR=0.1µF, Battery Simulator, unless otherwise noted. MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 9 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER TYPICAL PERFORMANCE CHARACTERISTICS (continued) VIN=5V, CIN=CBATT=CSYS=C3=22µF, C1=C2=1µF, L1=2.2µH, RS1=50mΩ, C4=CTMR=0.1µF, Battery Simulator, unless otherwise noted. MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 10 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER TYPICAL PERFORMANCE CHARACTERISTICS (continued) VIN=5V, CIN=CBATT=CSYS=C3=22µF, C1=C2=1µF, L1=2.2µH, RS1=50mΩ, C4=CTMR=0.1µF, Battery Simulator, unless otherwise noted. VSYS 1V/div. VBATT 1V/div. VBATT 1V/div. VBATT 2V/div. VSYS 2V/div. VSYS 1V/div. BOOST 2V/div. IL 500mA/div. IL 500mA/div. VSYS/AC 200mV/div. VSYS/AC 200mV/div. VSYS/AC 200mV/div. VBATT 1V/div. VBATT 1V/div. VBATT 1V/div. ISYS 500mA/div. ISYS 500mA/div. ISYS 500mA/div. 100 100 90 90 80 80 70 70 60 60 50 50 40 40 30 0 0.25 0.5 0.75 1 30 0 0.25 0.5 0.75 1 MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 11 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER PIN FUNCTIONS Pin # Name 1 FREQ 2 VIN 3 VCC 4 ILIM 5 PWIN 6 TMR 7 REG 8 ---------------- Description Connect to GND to program the operating frequency to 600kHz. Leave floating or connect to HIGH to program the operating frequency to 1.2MHz. Adapter Input. Place a bypass capacitor close to this pin to prevent large input voltage spikes. Internal Circuit Power Supply. Bypass to GND with a 100nF ceramic capacitor. This pin can not carry external load higher than 5mA. Input Current Set. Connect to GND with an external resistor to program input current limit in charge mode. AC Input Detect. Detect the presence of valid input power. Oscillator Period Timer. Connect a timing capacitor between this pin and GND to set the oscillator period. Short to GND to disable the Timer function. Input Voltage Feedback. Connect to tap of an external resistor divider from VIN to GND. The voltage on this pin should be always exceeded 1.2V during normal operation. Valid Input Supply Indicator. Logic LOW indicates the presence of a valid power supply. 9 10 11 ACOK FB NTC ISET 23 MODE 24 EN Mode Select. Logic HIGH→boost mode. Logic LOW→sleep mode. Active only when ACOK is HIGH (input power is not available). Charge Control Input. Logic HIGH enables charging. Logic LOW disables charging. Active only System Voltage Feedback. Negative Temperature Coefficient (NTC) Thermistor. Charge Current Set. Connect an external resistor to GND to program the charge current. Boost-Output-Current Limit Set. Connect an external resistor to GND to program the system 12 OLIM current in boost mode. 13 AGND Analog Ground Programmable Battery-Full Voltage. Connect to GND for 3.6V. Leave floating or connect to 14 VB logic HIGH for 4.2V. 15 BATT Positive Battery Terminal / Battery Charge Current Sense Negative Input. 16 CSP Battery Charge Current Sense, Positive Input. ------------------Boost Mode Indicator. Logic LOW indicates boost mode in operation. This pin becomes an 17 BOOST open drain when the part operates in charge mode or sleep mode. -----------Charge Completion indicator. Logic LOW indicates charge mode. The pin becomes an open 18 CHG drain once the charging has completed or is suspended. PGND, 19 Exposed Power Ground. Connect the exposed pad and GND pin to the same ground plane. Pad 20 SW Switch Output Node. System Output. Please make sure the enough bulk capacitors from SYS to GND. Suggest 21, 22 SYS 4.7uF at least. __________ __________ when ACOK is low (input power is OK) MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 12 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER SYS Q1 VIN FB Q2 SW HSMOS Buffer LSMOS A1 VCC Current Sense Driver VBATT K1*ICHG CSP BATT PWM Signal Charge Pump A2 PGND ACOK VBATT PWIN FREQ 0.8V Mode Control 1.15V VCC VSYS Control Logic & Mode Selection BATT+ 300mV SYS NTC TRef MODE TJ EN VB GMT VBATT_Ref Thermal Shutdown VBATT REG ISET MIN GMI ICHG_Ref ACOK GMV GMINV VREG_Ref CHG Indication& Timer BOOST K1*ICHG ILIM Current Setting OLIM PWM Controller I IN_Ref GMINI K2*I IN TMR AGND Figure 1: Functional Block Diagram,in Charge Mode MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 13 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER SYS Q1 VIN FB Q2 SW HSMOS A1 VCC CSP LSMOS Driver VBATT Charge Pump BATT PWM Signal Integration PGND A2 ACOK To Current Setting VBATT PWIN FREQ 0.8V Mode Control 1.15V VCC PWM Controller Control Logic & Mode Selection BATT+ 300mV NTC MODE EN VB VSYS_Ref Thermal Shutdown VFB ACOK GMV REG CHG Indication& Timer BOOST ISET IOLIM_Ref ILIM Current Setting OLIM GMINI K3*ISYS TMR AGND Figure 2: Functional Block Diagram, in Boost Mode MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 14 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER OPERATION FLOW CHART POR Yes VCC<VCC_UVLO No VPWIN_L<VPWIN<VPWIN _H &VIN>VBATT+300mV Yes No /ACOK is Low, System Powered By IN MODE High? No EN High? Yes No Boost Mode /BOOST Low Sleep Mode Yes Charger Mode /CHG Low Figure 3: Mode Selection Flow Chart MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 15 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER OPERATION FLOW CHART (Continued) Normal Operation Charger Mode /CHG Low Charge Mode? VBATT>VBATT_FULL VBATT_TC<VBATT<VBATT_FULL VBATT<VBATT_TC C.V.C C.C.C T.C.C No No No ICHG<IBF Battery Full VBATT>VBATT_FULL VBATT>VBATT_TC Yes Yes Yes Charger “Off”, /CHG is high Yes No VBATT< VRECH ? No No No o Timer Out ? NTC Fault? TJ ≥120 C? Yes Yes Yes Charge Termination, /CHG is high Charge Suspend, /CHG is high Decrease ICHG to maintain TJ at 120oC No No No Reset Timer? NTC OK? TJ ≥150oC? Yes Yes Yes Charger Recovery, Return to Normal Operation Thermal Shutdown, /CHG is high No Fault Protection Yes TJ ≤120oC? Figure 4: Normal Operation and Fault Protection in Charge Mode MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 16 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER OPERATION FLOW CHART (Continued) Power Path Management SYS Output Current Increase No VPWIN touch the VREG? No I IN hit the IIN_LIMIT ? Yes Yes Charge Current Decrease I CHG =0? No Yes I IN >7A? Normal Operation No IIN exceeds IIN(OCP)? No Yes Regulate the IIN at IIN(OCP) No Yes TINOCBLK reaches? Yes Yes IN to SYS MOSFET turns Off No TINRECVR reaches? Figure 5: Power-Path Management in Charge Mode MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 17 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER OPERATION FLOW CHART (Continued) Boost Mode /BOOST Low Normal Boost Operation No No ISYS > IOLIM? VBATT >2.9V? Yes Yes Output current loop works, VSYS decreases No No Mode High? VSYS < VBATT? Yes Yes Normal Boost Operation VSYS < 2V? No VBATT<2.5V? Yes Boost Turns Off No No Yes Yes Down mode IL hits the current limit TSYSBLK Reaches? Yes Yes Boost Shutdown No T SYSRECVR Reaches? Figure 6: Operation Flow Chart in Boost Mode MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 18 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER START UP TIME FLOW IN CHARGE MODE Condition: EN = 5V, Mode = 0V, /ACOK and /CHG are always pulled up to an external constant 5V VIN V PWIN > 0.8V & V IN > V BATT+ 300mV 0V 5V EN 0V Mode 0V VCC VCC follows V IN 2.2V Band Gap 0V 5V ACOK 0V V SYS > V BATT + 50mV VSYS 5V CHG 0V SS 150µs 150µs Force Charge ICC Charge 0A Current 10%ICC IBF Comparator Battery Voltage VBATT_FULL Auto‐recharge threshold Assume vBATT > V BATT_TC Autorecharge Figure 7: Input Power Start-Up Time Flow in Charge Mode MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 19 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER START UP TIME FLOW IN CHARGE MODE Condition: VIN = 5V, Mode = 0V, /ACOK and /CHG are always pulled up to an external constant 5V. VIN 0V 5V EN 0V Mode 0V VCC 2.2V Band Gap 0V 5V ACOK 0V VSYS 5V CHG 0V SS 150µs 150µs Force Charge ICC Charge 0A Current 10%ICC IBF Comparator VBATT_FULL Battery Voltage Assume vBATT > V BATT_TC Autorecharge Figure 8: EN Start-Up Time Flow in Charge Mode MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 20 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER START UP TIME FLOW IN BOOST MODE Condition: VIN = 0V, Mode = 5V, /Boost is always pulled up to an external constant 5V. 2.5V 2.9V VBATT 0V 0V VCC follows VBATT VCC follows V SYS 2.2V VCC MODE Band Gap 5V BOOST 0V Boost SS VSYS Down Mode 0V V SYS>VBATT+300mV Figure 9: Battery Power Start-Up Time Flow in Boost Mode MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 21 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER START UP TIME FLOW IN BOOST MODE Condition: VIN = 0V, /Boost is always pulled up to an external constant 5V. VBATT 2.9V VCC follows V SYS VCC follows V BATT V CC 2.2V 5V 0V MODE 5V Band Gap 0V 5V BOOST 0V Boost SS VSYS Down Mode 0V VSYS >V BATT+300mV Figure 10: Mode Start-Up Time Flow in Boost Mode MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 22 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER voltage falls below the auto-recharge threshold OPERATION INTRODUCTION CC>>>CV Threshold The MP2633A is a highly-integrated, synchronous, switching charger with bidirectional operation for a boost function that can step-up the battery voltage to power the system. Depending on the VIN value, it operates in one of three modes: charge mode, boost mode and sleep mode. In charge mode, the MP2633A supports a precision Li-ion or Li-polymer charging system for single-cell applications. In boost mode, MP2633A boosts the battery voltage to VSYS to power higher-voltage systems. In sleep mode, the MP2633A stops charging or boosting and operates at a low current from the input or the battery to reduce power consumption when the IC isn’t operating. The MP2633A monitors VIN to allow smooth transition between different modes of operation. VBAT TC>>>CC Threshold Trickle Charge Current Trickle charge CC charge CV charge Charge Full a) Without input current limit Constant Charge Current CC>>>CV Threshold ICHG Input Current Limit VBAT TC>>>CC Threshold Trickle Charge Current Trickle charge CC charge CV charge Charge Full b) With input current limit CHARGE MODE OPERATION Figure 11: Typical Battery Charging Profile Charge Cycle (Trickle ChargeCC ChargeCV Charge) In charge mode, the MP2633A has four control loops to regulate the input current, charge current, charge voltage, and device junction temperature. It charges the battery in three phases: trickle current (TC), constant current (CC), and constant voltage (CV). While charging, all four loops are active but only one determines the IC behavior. Figure 11(a) shows a typical battery charge profile. The charger stays in TC charge mode until the battery voltage reaches a TC-to-CC threshold. Otherwise the charger enters CC charge mode. When the battery voltage rises to the CV-mode threshold, the charger operates in constant voltage mode. Figure 11(b) shows a typical charge profile when the input-current-limit loop dominates during the CC charge mode, and in this case the charge current exceeds the input current, resulting in faster charging than a traditional linear solution that is well-suited for USB applications. Auto-Recharge Once the battery charge cycle completes, charger remains off. During this process, system load may consume battery power, or battery may self discharge. To ensure that ICHG Constant Charge Current the the the the and the input power is present. The timer resets when the auto-recharge cycle begins. During the off state after the battery is fully charged, if the input power re-starts or the EN signal refreshes, the charge cycle will start and the timer will reset no matter what the battery voltage is. Battery Over-Voltage Protection The MP2633A has battery over-voltage protection. If the battery voltage exceeds the battery over-voltage threshold, (103.3% of the battery-full voltage), charging is disabled. Under this condition, an internal current source draws a current from the BATT pin to decrease the battery voltage and protect the battery. Timer Operation in Charge Mode The MP2633A uses an internal timer to terminate the charging. The timer remains active during the charging process. An external capacitor between TMR and GND programs the charge cycle duration. MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 23 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER If charging remains in TC mode beyond the trickle-charge time τTOTAL_TMR, charging will terminate. The following determines the length of the trickle-charge period: 120µs blanking time, Q2 will turn off. A fast off function turns off Q2 quickly when the input current exceeds 7A to protect both Q1 and Q2. C (F) 1A (1) 60 min s TMR 0.1F ICHG ( A ) The external sense resistors, RS1 and RISET, program the battery charge current, ICHG. Select RISET based on RS1: TRICKLE _ TMR The maximum total charge time is: TOTAL _ TMR 6Hours CTMR (F) 1A 0.1F ICHG ( A ) ICHG (A)= (2) Negative Temperature Coefficient (NTC) Input for Battery Temperature Monitoring The MP2633A has a built-in NTC resistance window comparator, which allows the MP2633A to monitor the battery temperature via the battery-integrated thermistor. Connect an appropriate resistor from VSYS to the NTC pin and connect the thermistor from the NTC pin to GND. The resistor divider determines the NTC voltage depending on the battery temperature. If the NTC voltage falls outside of the NTC window, the MP2633A stops charging. The charger will then restart if the temperature goes back into NTC window range. Input-Current Limiting in Charge Mode The MP2633A has a dedicated pin that programs the input-current limit. The current at ILIM is a fraction of the input current; the voltage at ILIM indicates the average input current of the switching regulator as determined by the resistor value between ILIM and GND. As the input current approaches the programmed input current limit, charge current is reduced to allow priority to system power. Use the following equation to determine the input current limit threshold, 40.5(kΩ) IILIM = (A) RILIM (kΩ) Setting the Charge Current (3) 70(kΩ) 40(mV) RISET (kΩ) RS1(mΩ) (4) Where the 40mV is the charge current limit reference. RISET can not be larger than 70k always. Battery Short Protection The MP2633A has two current limit thresholds. CC and CV modes have a peak current limit threshold of 3A, while TC mode has a current limit threshold of 1.5A. Therefore, the current limit threshold decreases to 1.5A when the battery voltage drops below the TC threshold. Moreover, the switching frequency also decreases when the BATT voltage drops to 40% of the charge-full voltage. Thermal Foldback Function The MP2633A implements thermal protection to prevent thermal damage to the IC and the surrounding components. An internal thermal sense and feedback loop automatically decreases the programmed charge current when the die temperature reaches 120°C. This function is called the charge-current-thermal foldback. Not only does this function protect against thermal damage, it can also set the charge current based on requirements rather than worst-case conditions while ensuring safe operation. Furthermore, the part includes thermal shutdown protection where the ceases charging if the junction temperature rises to 150°C. Fully Operation Indication The MP2633A integrates indicators for the following conditions as shown in Table 2. Input Over-Current Protection The MP2633A features input over-current protection (OCP): when the input current exceeds 3A, Q2 is controlled linearly to regulate the current. If the current still exceeds 3A after a MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 24 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER Table 2: Indicator for Each Operation Mode ---------------- Operation ACOK Charging Charge Mode ------------ CHG ------------------- BOOST Low End of Charge, charging disabled Low High High Blinking NTC Fault, Timer Out Boost Mode High High Low Sleep Mode, VCC absent High High High BOOST MODE OPERATION Low-Voltage Start-Up The minimum battery voltage required to start up the circuit in boost mode is 2.9V. Initially, when VSYS < VBATT, the MP2633A works in down mode. In this mode, the synchronous P-MOSFET stops switching and its gate connects to VBATT statically. The P_MOSFET keeps off as long as the voltage across the parasitic CDS (VSW) is lower than VBATT. When the voltage across CDS exceeds VBATT, the synchronous P-MOSFET enters a linear mode allowing the inductor current to decrease and flowing into the SYS pin. Once VSYS exceeds VBATT, the P-MOSFET gate is released and normal closed-loop PWM operation is initiated. In boost mode, the battery voltage can drop to as low as 2.5V without affecting circuit operation. SYS Disconnect and Inrush Limiting The MP2633A allows for true output disconnect by eliminating body diode conduction of the internal P-MOSFET rectifier. VSYS can go to 0V during shutdown, drawing no current from the input source. It also allows for inrush current limiting at start-up, minimizing surge currents from the input supply. To optimize the benefits of output disconnect, avoid connecting an external Schottky diode between the SW and SYS pins. Board layout is extremely critical to minimize voltage overshoot at the SW pin due to stray inductance. Keep the output filter capacitor as close as possible to the SYS pin and use very low ESR/ESL ceramic capacitors tied to a good ground plane. Boost Output Voltage The MP2633A programs the output voltage via the external resistor divider at FB pin, and provides built-in output over-voltage protection (OVP) to protect the device and other components against damage when VSYS goes beyond 6V. Should output over-voltage occur, the MP2633A turns off the boost converter. Once VSYS drops to a normal level, the boost converter restarts again as long as the MODE pin remains in active status. Boost Output-Current Limiting The MP2633A integrates a programmable output current limit function in boost mode. If the boost output current exceeds this programmable limit threshold, the output current will be limited at this level and the SYS voltage will start to drop down. The OLIM pin programs the current limit threshold up to 1A as per the following equation: 70(kΩ) 40(mV) (5) IOLIM (A)= ROLIM (kΩ) RS1(mΩ) Where the 40mV is the charge current limiting reference. SYS Output Over Current Protection The MP2633A integrates three-phase output over-current protection. Phase one (boost mode): when the output current exceeds the output current limit, the output constant current loop controls the output current, the output current remains at its limit of IOLIM, and VSYS decreases. Phase two (down mode): when VSYS drops below VBATT+100mV and the output current loop remains in control, the boost converter enters down mode and shutdown after a 120μs blanking time. MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 25 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER Phase three (short circuit mode): when VSYS drops below 2V, the boost converter shuts down immediately once the inductor current hits the fold-back peak current limit of the low side NMOSFET. The boost converter can also recover automatically after a 500µs deglitch period. Thermal Shutdown Protection Thermal shutdown protection is also active in boost mode. Once the junction temperature rises higher than 150°C, the MP2633A enters thermal shutdown. It will not resume normal operation until the junction temperature drops below 120°C MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 26 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER APPLICATION INFORMATION COMPONENT SELECTION VPWIN VIN Setting the Charge Current in Charge Mode In charge mode, both the external sense resistor, RS1, and the resistor RISET connect to the ISET pin to set the charge current (ICHG) of the MP2633A (see the Typical Application circuit). Given ICHG and RS1, the regulation threshold, VIREF, across this resistor is: VIREF (mV ) RS1(m ) ICHG ( A ) (6) 70(k ) 40(mV ) R ISET (k ) (7) So, the RISET can be calculated as: RISET (k ) 70(k ) 40(mV ) VIREF (mV ) For example, for ICHG=1.5A and RS1=50mΩ: VIREF=75mV, so RISET=37.4kΩ. Setting the Input Current Limiting in Charge Mode In charge mode, connect a resistor from the ILIM pin to AGND to program the input current limit. The relationship between the input current limit and setting resistor is: RILIM 40.5 (k) IIN _ LIM ( A ) For a wide operating range, use a maximum input voltage of 6V as the upper threshold for a voltage ratio of: (9) Where RILIM must exceed 20kΩ so that IIN_LIM is in the range of 0A to 2A. For most applications, use RILIM = 45kΩ (IUSB_LIM=900mA) for USB3.0, and use an RLIM = 81kΩ (IUSB_LIM=500mA) for USB2.0. Setting the Input Voltage Range for Different Operation Modes A resistive voltage divider from the input voltage to PWIN pin determines the operating mode of MP2633A. (11) With the given R6, R4 is then: R4 (8) (10) If the voltage on PWIN is between 0.8V and 1.15V, the MP2633A works in the charge mode. While the voltage on the PWIN pin is not in the range of 0.8V to 1.15V and VIN > 2V, the MP2633A works in the boost mode (see Table 1). VPWIN 1.15 R6 VIN 6 R4 R6 RISET sets VIREF as per the following equation: VIREF (mV ) R6 (V) R4 R6 VIN VPWIN R6 VPWIN (12) Consider these resistors as the dummy load at the input port. Use resistors in the hundreds of ohms range to shorten the power-off time. For a typical application, start with R6=51Ω, R4 is 215Ω. REG Voltage Setting REG pin is the feedback input of the input voltage. Connect this pin to external resistor divider from VIN to GND. The voltage on this pin should be always higher than 1.2V when normal operation. VREG R5 VIN_MIN 1.2V R3 R5 (13) Consider these resistors as the dummy load at the input port. Use resistors in the hundreds of ohms range to shorten the power-off time. If VIN_MIN=4.25V, given R5=51Ω, R3=127Ω. NTC Function in Charge Mode Figure 12 shows that an internal resistor divider sets the low temperature threshold (VTL) and high temperature threshold (VTH) at 65%·VSYS and 35%·VSYS, respectively. For a given NTC thermistor, select an appropriate RT1 and RT2 to set the NTC window. MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 27 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER RT2//RNTC_Cold VTL TL 65% VSYS RT1 RT2//RNTC_Cold (14) R T2 //RNTC_Hot VTH TH 35% (15) VSYS R T1 R T2 //RNTC_Hot Where RNTC_Hot is the value of the NTC resistor at the upper bound of its operating temperature range, and RNTC_Cold is its lower bound. The two resistors, RT1 and RT2, independently determine the upper and lower temperature limits. This flexibility allows the MP2633A to operate with most NTC resistors for different temperature range requirements. Calculate RT1 and RT2 as follows: R T1 RT2 R NTC_Hot R NTC_Cold (TL TH) TH TL (RNTC_Cold R NTC_Hot ) (TL TH) RNTC_Cold RNTC_Hot (1 TL) TH RNTC_Cold- (1- TH) TL RNTC_Hot (16) (17) For example, the NCP18XH103 thermistor has the following electrical characteristic: At 0°C, RNTC_Cold = 27.445kΩ; At 50°C, RNTC_Hot = 4.1601kΩ. Based on equation (16) and equation (17), RT1=6.47kΩ and RT2 = 21.35kΩ are suitable for an NTC window between 0°C and 50°C. Chose approximate values: e.g., RT1=6.49kΩ and RT2=21.5kΩ. If no external NTC is available, connect RT1 and RT2 to keep the voltage on the NTC pin within the valid NTC window: e.g., RT1 = RT2 = 10kΩ. Low Temp Threshold NTC RT2 Setting the Output Current Limit in Boost Mode In boost mode, connect a resistor from the OLIM pin to AGND to program the output current limit. The relationship between the output current limit and setting resistor is as follows: 70(k ) 40(mV ) (20) IOLIM ( A ) RS1(m ) Where ROLIM is greater than 56kΩ, so IOLIM can be programmed up to 1A. R OLIM (k ) Selecting the Inductor Inductor selection trades off between cost, size, and efficiency. A lower inductance value corresponds with smaller size, but results in higher ripple currents, higher magnetic hysteretic losses, and higher output capacitances. However, a higher inductance value benefits from lower ripple current and smaller output filter capacitors, but results in higher inductor DC resistance (DCR) loss. Choose an inductor that does not saturate under the worst-case load condition. 1. Charge Mode SYS RT1 regulated to the value customer required between 4.2V to 6V by the resistor divider at FB pin as R1 and R2 in the typical application circuit. R1 R2 (18) VSYS 1.2V R2 Where, 1.2V is the voltage reference of SYS. With a typical value for R2, 10kΩ, R1 can be determined by: V 1.2V (19) R1 SYS R2 1.2V For example, for a 5V system voltage, R2 is 10kΩ, and R1 is 31.6kΩ. VTL RNTC When MP2633A works in charge mode (as a buck converter), estimate the required inductance as: V VBATT V (21) L IN BATT IL _ MAX VIN fS High Temp Threshold V TH Figure 12: NTC Function Block Setting the System Voltage in Boost Mode In the boost mode, the system voltage can be MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 28 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER Where VIN, VBATT, and fS are the typical input voltage, the CC charge threshold, and the switching frequency, respectively. ∆IL_MAX is the maximum inductor ripple current, which is usually designed at 30% of the CC charge current. With a typical 5V input voltage, 30% inductor current ripple at the corner point between trickle charge and CC charge (VBATT=3V), the inductance is 1.85μH (for a 1.2MHz switching frequency), and 3.7µH (for a 600kHz switching frequency). noise from the device. The input capacitor impedance at the switching frequency should be less than the input source impedance to prevent high-frequency-switching current from passing to the input. For best results, use ceramic capacitors with X5R or X7R dielectrics because of their low ESR and small temperature coefficients. For most applications, a 22µF capacitor will suffice. Selecting the System Capacitor, CSYS Select CSYS based on the demand of the system current ripple. 2. Boost Mode 1. Charge Mode When the MP2633A is in boost mode (as a boost converter), the required inductance value is calculated as: The capacitor CSYS acts as the input capacitor of the buck converter in charge mode. The input current ripple is: L VBATT ( VSYS VBATT ) VSYS fS IL _ MAX IL _ MAX (30% 40%) IBATT (MAX ) IBATT (MAX ) VSYS ISYS VBATT (22) (23) (24) Where VBATT is the minimum battery voltage, fSW is the switching frequency, and ∆IL_MAX is the peak-to-peak inductor ripple current, which is approximately 30% of the maximum battery current, IBATT(MAX). ISYS(MAX) is the system current and η is the efficiency. In the worst case where the battery voltage is 3V, a 30% inductor current ripple, and a typical system voltage (VSYS=5V), the inductance is 1.8μH (for a 1.2MHz switching frequency) and 3.6µH (for a 600kHz switching frequency) when the efficiency is 90%. For best results, use an inductor with an inductance of 1.8μH (for a 1.2MHz switching frequency) and 3.6µH (for a 600kHz switching frequency) with a DC current rating that is at least 30% higher than the maximum charge current for applications. For higher efficiency, minimize the inductor’s DC resistance. IRMS _ MAX ISYS _ MAX VTC ( VIN _ MAX VTC ) VIN _ MAX (25) 2. Boost Mode The capacitor, CSYS, is the output capacitor of boost converter. CSYS keeps the system voltage ripple small and ensures feedback loop stability. The system current ripple is given by: IRMS _ MAX ISYS _ MAX VTC ( VSYS _ MAX VTC ) (26) VSYS _ MAX Since the input voltage passes to the system directly, VIN_MAX=VSYS_MAX, both charge mode and boost mode have the same system current ripple. For ICC_MAX=2A, VTC=3V, VIN_MAX=6V, the maximum ripple current is 1A. Select the system capacitors base on the ripple-current temperature rise not exceeding 10°C. For best results, use ceramic capacitors with X5R or X7R dielectrics with low ESR and small temperature coefficients. For most applications, use a 22µF capacitor. Selecting the Battery Capacitor, CBATT CBATT is in parallel with the battery to absorb the high-frequency switching ripple current. Selecting the Input Capacitor, CIN The input capacitor CIN reduces both the surge current drawn from the input and the switching MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 29 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER 1. Charge Mode The capacitor CBATT is the output capacitor of the buck converter. The output voltage ripple is then: Place the input capacitor as close as possible to the VIN and PGND pins. The local power input capacitors, connected from the SYS to PGND, must be placed as close as possible to the IC. (27) Place the output inductor close to the IC and connect the output capacitor between the inductor and PGND of the IC. The capacitor CBATT is the input capacitor of the boost converter. The input voltage ripple is the same as the output voltage ripple from equation (27). 2) For high-current applications, the power pads for IN, SYS, SW, BATT and PGND should be connected to as many copper planes on the board as possible. The exposed pad should connect to as many GND copper planes in the board as possible. This improves thermal performance because the board conducts heat away from the IC. rBATT 1 VBATT / VSYS VBATT 2 VBATT 8 C BATT fS L 2. Boost Mode Both charge mode and boost mode have the same battery voltage ripple. The capacitor CBATT can be calculated as: C BATT 1 VTC / VSYS _ MAX 2 8 rBATT _ MAX fS L (28) To guarantee the ±0.5% BATT voltage accuracy, the maximum BATT voltage ripple must not exceed 0.5% (e.g., 0.1%). The worst case occurs at the minimum battery voltage of the CC charge with the maximum input voltage. For VSYS_MAX=6V, VCC_MIN=VTC=3V, L=3.9µH, fS=600kHz or 1.2MHz, rBATT _ MAX 0.1% , CBATT is 22µF (for a 600kHz switching frequency) or 10µF (for a 1.2MHz switching frequency). 3) The PCB should have a ground plane connected directly to the return of all components through vias (e.g., two vias per capacitor for power-stage capacitors, one via per capacitor for small-signal components). If possible, add vias inside the exposed pads for the IC. A star ground design approach is typically used to keep circuit block currents isolated (power-signal/controlsignal), which reduces noise-coupling and ground-bounce issues. A single ground plane for this design gives good results. 4) Place ISET, OLIM and ILIM resistors very close to their respective IC pins. A 22µF ceramic with X5R or X7R dielectrics capacitor in parallel with a 220uF electrolytic capacitor will suffice. PCB Layout Guide PCB layout is very important to meet specified noise, efficiency and stability requirements. The following design considerations can improve circuit performance: 1) Route the power stage adjacent to their grounds. Aim to minimize the high-side switching node (SW, inductor) trace lengths in the highcurrent paths and the current sense resistor trace. Keep the switching node short and away from all small control signals, especially the feedback network. MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 30 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER Design Example Below is a design example following the application guidelines for the specifications: Table 3: Design Example VIN VOUT fSW Top Layer 5V 3.7V 1200kHz Figure14 shows the detailed application schematic. The Typical Performance Characteristics section shows the typical performance and circuit waveforms. For more possible applications of this device, please refer to the related Evaluation Board datasheets. Bottom Layer Figure 13 PCB Layout Guide MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 31 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER SYS R1 31.6k 1% C8 C2 SYS R2 C7 10k 1% CSYS ROLM 47pF PGND 56k 1% R3 51 110 2 PGND 7 VCC R6 10k C4 JP1 JP2 R7 10k JP3 R8 10k 5 REG VCC 3 24 23 4 SW NTC VCC VB CHG FREQ ACOK EN BOOST MODE ISET ILIM TMR VBATT BATT 50m 20 C3 CBATT C6 16 15 NTC SYS 10 RT2 13 RILIM L1 BATT PWIN RS1 SW 1 CSP MP2633A 1 AGND VIN PGND VCC 12 R4 U1 OLIM 215 9 51 FB FB C1 RH 14 10k RT1 10k JP4 10k 2 SYS VCC R5 18 LED1 8 LED2 17 LED3 11 2k R9 2k R10 RISET 6 LED JP5 2k R11 VBATT CTMR 100nF 19 CIN RL AGND C5 21,22 VIN SYS VIN Figure14: Detailed Application Circuit MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 32 MP2633A – 1.5A SINGLE CELL SWITCH MODE BATTERY CHARGER PACKAGE INFORMATION QFN24 (4x4mm) 3.90 4.10 2.50 2.80 19 PIN 1 ID MARKING 18 3.90 4.10 PIN 1 ID INDEX AREA PIN 1 ID SEE DETAIL A 24 1 0.50 BSC 2.50 2.80 0.18 0.30 6 13 0.35 0.45 TOP VIEW 12 7 BOTTOM VIEW PIN 1 ID OPTION A 0.30x45º TYP. PIN 1 ID OPTION B R0.25 TYP. 0.80 1.00 0.20 REF 0.00 0.05 DETAIL A SIDE VIEW 3.90 2.70 0.70 0.25 NOTE: 1) ALL DIMENSIONS ARE IN MILLIMETERS. 2) EXPOSED PADDLE SIZE DOES NOT INCLUDE MOLD FLASH. 3) LEAD COPLANARITY SHALL BE0.10 MILLIMETER MAX. 4) DRAWING CONFIRMS TO JEDEC MO-220, VARIATION VGGD. 5) DRAWING IS NOT TO SCALE. 0.50 RECOMMENDED LAND PATTERN NOTICE: The information in this document is subject to change without notice. Please contact MPS for current specifications. Users should warrant and guarantee that third party Intellectual Property rights are not infringed upon when integrating MPS products into any application. MPS will not assume any legal responsibility for any said applications. MP2633A Rev. 1.03 www.MonolithicPower.com 4/27/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 33