® RT9455 Switch-Mode Single Cell Li-Ion Battery Charger with USB-OTG General Description Features The RT9455 is a switch-mode single cell Li-Ion/Li-Polymer battery charger for portable applications. It integrates a synchronous PWM controller, power MOSFETs, input current sensing, high accuracy voltage regulation and charge termination circuits. The RT9455 also features USB On-The-Go (OTG). The RT9455 optimizes the charging task by using a control algorithm to vary the charge rate via different modes, including pre-charge mode, fast charge mode, and constant voltage mode. The key charge parameters can be programmed via the I2C interface. The RT9455 resumes the charge cycle whenever the battery voltage falls below an internal threshold and automatically enters sleep mode when the input power supply is removed. Other features include under-voltage protection, overvoltage protection, thermal regulation and reverse leakage protection. The RT9455 is available in the small WL-CSP-16B 1.7x1.77 (BSC) package. Marking Information 1A : Product Code 1AW W : Date Code Support Quick Start for Charger High Accuracy Voltage/Current Regulation Input Current Regulation : 100mA/500mA/700mA/ 1A Minimum Input Voltage Regulation : 4V/4.25V/4.5V Charge Voltage Regulation Accuracy : ±1% (0 to 85°°C) Charge Current Regulation Accuracy : ±5% Built-In Input Current Sensing and Limiting Integrated Power MOSFETS for up to 1.55A Charge Rate Integrated Sensing Resistors for Charging Current Sensing Synchronous 1.5MHz Fixed Frequency PWM Controller with up to 95% Duty Cycle Reverse Leakage Protection to Prevent Battery Drainage Thermal Regulation and Protection Over-Temperature Protection Input Over-Voltage Protection IRQ Output for Communication with I2C Automatic Charging RoHS Compliant and Halogen Free Applications Cellular Telephones Personal Information Appliances MP3 Players Portable Instruments Simplified Application Circuit To Adaptor/USB VIN OTG SCL SDA IRQ VMID RT9455 LX ISNSIN BATS GND Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9455-00 April 2014 + Battery is a registered trademark of Richtek Technology Corporation. www.richtek.com 1 RT9455 Ordering Information Pin Configurations RT9455 (TOP VIEW) Package Type WSC : WL-CSP-16B 1.7x1.77 (BSC) Note : Richtek products are : RoHS compliant and compatible with the current requirements of IPC/JEDEC J-STD-020. Suitable for use in SnPb or Pb-free soldering processes. A1 A2 A3 A4 VIN VIN IRQ BATS B1 B2 B3 B4 VMID VMID OTG ISNSIN C1 C2 C3 C4 LX LX AGND SCL D1 D2 PGND PGND D3 D4 BOOT SDA WL-CSP-16B 1.7x1.77 (BSC) Functional Pin Description Pin No. Pin Name Pin Function A1, A2 VIN Power Input. A3 IRQ IRQ Output Node. A4 BATS Feedback Voltage Input for Battery. B1, B2 VMID Connection Point Between Reverse Blocking MOSFET and High-Side MOSFET. B3 OTG Boost Mode Control Input or Current Regulation Setting for Average Input Current. B4 ISNSIN Charge Current Sense Input. LX Switch Node. C3 AGND Analog Ground. C4 SCL Clock Input for I C. Open-drain output, connect a 10k pull-up resistor. D1, D2 PGND Power Ground for Switching Charger. D3 BOOT Bootstrap Supply for High-Side MOSFET. Connect a capacitor between BOOT and LX. D4 SDA Data Input for I C. Open-drain output, connect a 10k pull-up resistor. C1, C2 2 Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 2 2 is a registered trademark of Richtek Technology Corporation. DS9455-00 April 2014 RT9455 Function Block Diagram VIN Protection OVP, UVLO, OTP, Timer Gate Driver 1 VMID BOOT Loop Control Base VDD, Ibias, VREF, OSC Gate Driver 2 LX PGND SCL SDA 2 I C State Machine Current Sense ISNSIN BATS AGND OTG IRQ Operation The RT9455 is a switch mode charger with USB-OTG support for single cell Li-Ion battery in portable applications. Loop Controller and PWM and Driver Base circuits provide the internal power, VDD and reference voltage and bias current. The multi-loop controller controls the PWM signal during the charging process. The PWM circuit controls the power stage through the driver. It makes sure that the battery is well-charged with suitable current, voltage and dietemperature. Current Sense I2C Interface Current sense circuit regulates the output current up to 1.5A to battery The I 2C interface is used to program the charging parameters, ex : output current and output voltage. Protection Circuits State Machine The protection block includes the OVP, UVLO, OTP, Timer and other circuits. It turns off the charging when the charger IC or input power is in abnormal level. The State Machine controls the operation of the switching charger and outputs the interrupt via the IRQ pin if there is any fault be triggered. Base Circuits Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9455-00 April 2014 is a registered trademark of Richtek Technology Corporation. www.richtek.com 3 RT9455 Flow Charts Yes 2 Any I C? Yes No Charge Start TMR_EN = 1? Reset Timer --------------------T32min mode Yes No 2 Any I C? Yes Any state No 32 min? Yes Timer Fault ----------------------Disable Charging No VIN ,VBATS < 2.4V No POR Reset No VIN > 2.4V and Yes Yes VIN > 3.3V ? VBATS > 2.4V ? Charge Configure 2 (I C is Programmable) No 2 Clean I C Any State If VIN < 2.4V and VBATS < 2.4V Power On Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 4 is a registered trademark of Richtek Technology Corporation. DS9455-00 April 2014 RT9455 Charger Flow Power on disable charge ----------------Charge Configure Mode Yes 32 min timer fault? 2 No Load I C with default settings VBATS > VPREC? Any state No PreCharge Mode Yes Fast-Charge to CV mode No TE is enabled? Yes No ICHRG < IEOC? No Yes Yes BATD_EN is enabled? Yes Sink 0.5mA from battery ---------------------------------Start 262ms timer Yes No Charge done 262ms timer expired? No VBATS < VREC? Yes No VBATS < VREC ? Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9455-00 April 2014 Battery Detection Mode (Detect every 2s) is a registered trademark of Richtek Technology Corporation. www.richtek.com 5 RT9455 OTG Flow Battery power on No OPA_MODE = 1 and HZ = 0? OTG_EN = 1? Yes Yes No OTG_PL = 1? OTG Configure Mode Yes Yes No No OTG pin from low to high? Any fault except Over Load ? OTG pin from high to low? No No Yes No Yes OTG pin keeps high? OTG pin keeps low? OTG Mode Yes Yes No OTG Configure Mode OTG Configure Mode Yes Over Load ? Yes Any fault except Over Load ? Any fault except Over Load ? No Yes OTG Mode OTG Mode Yes No No Over Load ? Over Load ? Yes Yes Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 6 Set to HZ mode is a registered trademark of Richtek Technology Corporation. DS9455-00 April 2014 RT9455 Absolute Maximum Ratings (Note 1) Supply Input Voltage, VIN -----------------------------------------------------------------------------------------------MID, BOOT -----------------------------------------------------------------------------------------------------------------LX -----------------------------------------------------------------------------------------------------------------------------MID − VIN, BOOT − LX ---------------------------------------------------------------------------------------------------Other Pins -------------------------------------------------------------------------------------------------------------------Power Dissipation, PD @ TA = 25°C WL-CSP-16B 1.7x1.77 (BSC) ------------------------------------------------------------------------------------------Package Thermal Resistance (Note 2) WL-CSP-16B 1.7x1.77 (BSC), θJA ------------------------------------------------------------------------------------Lead Temperature (Soldering, 10 sec.) -------------------------------------------------------------------------------Junction Temperature -----------------------------------------------------------------------------------------------------Storage Temperature Range --------------------------------------------------------------------------------------------ESD Susceptibility (Note 3) HBM (Human Body Model) ----------------------------------------------------------------------------------------------MM (Machine Model) ------------------------------------------------------------------------------------------------------ Recommended Operating Conditions −0.3V to 20V −0.3V to 20V −0.3V to 10V −0.3V to 6V −0.3V to 6V 2.09W 47.8°C/W 260°C 150°C −65°C to 150°C 2kV 200V (Note 4) Supply Input Voltage, VIN ------------------------------------------------------------------------------------------------ 4.3V to 6V Junction Temperature Range --------------------------------------------------------------------------------------------- −40°C to 125°C Ambient Temperature Range --------------------------------------------------------------------------------------------- −40°C to 85°C Electrical Characteristics (VIN = 5V, VBAT = 4.2V, L = 1μH, CIN = 2.2μF, CBATS = 10μF, TA = 25°C, unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Unit 6.4 6.7 7 V -- 150 -- mV 110 117 124 % -- 10 -- % -- 165 -- °C -- 10 -- °C Charge Current Begins to Reduce -- 120 -- °C Protection VIN OVP Threshold Voltage VIN OVP Hysteresis (Battery OVP VOREG) / VOREG Battery OVP Battery OVP Hysteresis Over-Temperature Protection OTP OTP Hysteresis Thermal Regulation Threshold Sleep Mode Comparator Sleep-Mode Entry Threshold VIN VBATS VSLP 2.5V < VBATS < VBATREG, VIN Falling 0 0.04 0.1 V Sleep-Mode Exit Hysteresis VIN VBATS VSLPEXIT 2.5V < VBATS < VBATREG 40 100 200 mV Sleep-Mode Deglitch Time TSLP VIN Rising Above VSLP + VSLPEXIT -- 128 -- ms 3.05 3.3 3.55 V -- 150 -- mV Under-Voltage Lockout Threshold IC Active Threshold Voltage VUVLO VIN Rising IC Active Hysteresis VUVLO VIN Falling from UVLO Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9455-00 April 2014 is a registered trademark of Richtek Technology Corporation. www.richtek.com 7 RT9455 Parameter Symbol Test Conditions Min Typ Max Unit PWM switching, ICHRG = IBAT = 0mA -- 10 -- mA PWM Is Not Switching. ICHRG = IBAT = 0mA -- -- 5 mA High Impendence Mode -- -- 150 A IBAT VBATS = 4.2V, VIN = 0V, Charger Off. -- -- 15 A VMIVR I C Programmable Per 0.25V 4 -- 4.5 V 5 -- 5 % USB Charge Mode, IAICR = 100mA 80 90 100 USB Charge Mode, IAICR = 500mA 400 450 500 I C Programmable Per 20mV 3.5 -- 4.44 V 0 to 85°C 1 -- 1 % VBATS Falling, Below VBATREG 50 125 200 mV -- 128 -- ms I C Programmable Per 0.15A 0.5 -- 1.55 A 500mA to 1.55A 5 -- 5 % 2 -- 3 V 5 -- 5 % 20 -- 60 mA 50 -- 50 % I C Programmable Per 10% 10 -- 30 % As IAICR = 100mA -- 50 -- mA IEOC[1:0] = 00 5 10 15 IEOC[1:0] = 10 14 20 26 IEOC[1:0] = 01 or 11 24 30 36 ICHRG < IEOC, VBATS > VREC -- 32 -- s Internal MOSFET On-Resistance From VIN to LX, as IAICR[1:0] = 11 -- 300 450 m Internal MOSFET On-Resistance From LX to PGND -- 120 200 m Charging Efficiency VIN = 5V, VBATS = 4V, and ICHRG = 1A -- 85 -- % -- 1.5 -- MHz Input Currents VIN Supply Current Leakage Current from Battery IQ Input Power Regulation Minimum Input Voltage Regulation 2 VMIVR Accuracy Average Input Current Regulation Accuracy IAICR mA Battery Voltage Regulation Battery Voltage Regulation VBATREG VBATREG Accuracy Re-Charge Threshold VREC Re-Charge Deglitch TREC 2 Charging Current Regulation Output Charging Current ICHRG ICHRG Accuracy Pre-Charge Threshold VPREC 2 2 I C Programmable Per 0.2V VPREC Accuracy Pre-Charge Current IPREC 2 I C Programmable Per 20mA IPREC Accuracy Charge Termination Detection End of Charge Current IEOC Fixed IEOC IEOC Accuracy Deglitch Time for EOC TEOC 2 % PWM Oscillator Frequency OSC Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 8 is a registered trademark of Richtek Technology Corporation. DS9455-00 April 2014 RT9455 Parameter Symbol Test Conditions Min Typ Max Unit 10 -- 10 % -- 95 -- % 0 -- -- % 2 2.75 3.5 A 4.425 -- 5.6 V 3 -- 3 % -- 85 -- % 0.5 -- -- A 2.5 3.25 4 A -- 6 -- V -- 200 -- mV As Boost Start-Up 2.75 2.9 3.05 During Boost Mode 2.35 2.5 2.65 -- 200 -- mV -- -- 0.4 V Frequency Accuracy Maximum Duty Cycle At Minimum Voltage Input Minimum Duty Cycle Peak OCP as Charger Mode ICHRGOCP Boost Mode Operation 2 Output Voltage Level VOTG To VMID, I C Programmable Per 25mV Output Voltage Accuracy VIN = 5V, VBATS = 4V, and IIN = 0.4A Efficiency MAX Output Current Peak Over Current Protection VIN OVP as OTG Boost VBATS = 3.7V VIN OVP Hysteresis Minimum Battery Voltage for Boost VBATMIN Minimum Battery Voltage Hysteresis V 2 I C Characteristics Output Low Voltage VOL IDS = 10mA SCL, SDA Input Threshold Voltage VIH Logic High Threshold 1.3 -- -- VIL Logic Low Threshold -- -- 0.4 -- -- 400 SCL Clock V kHz Note 1. Stresses beyond those listed “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 may affect device reliability. Note 2. θJA is measured at TA = 25°C on a high effective thermal conductivity four-layer test board per JEDEC 51-7. Note 3. Devices are ESD sensitive. Handling precaution is recommended. Note 4. The device is not guaranteed to function outside its operating conditions. Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9455-00 April 2014 is a registered trademark of Richtek Technology Corporation. www.richtek.com 9 RT9455 Typical Application Circuit RT9455 To Adaptor/USB A1, A2 VIN 0.47µF VMID BOOT A4 OTG C4 SCL D4 SDA A3 IRQ LX ISNSIN www.richtek.com 10 0.47µF D3 100nF C1, C2 1µH B4 68m BATS AGND PGND D1, D2 C3 Copyright © 2014 Richtek Technology Corporation. All rights reserved. B1, B2 0.1µF A4 + Battery 10µF is a registered trademark of Richtek Technology Corporation. DS9455-00 April 2014 RT9455 Typical Operating Characteristics Charge Mode Efficiency vs. VBAT Efficiency vs. VBAT 94 94 92 92 90 88 86 VIN VIN VIN VIN 84 82 = = = = 4.5V 5V 5.5V 6V 80 Efficiency (%) Efficiency (%) 90 88 86 84 VIN VIN VIN VIN 82 80 78 = = = = 4.5V 5V 5.5V 6V ICHRG = 950mA, no input current limit ICHRG = 500mA, no input current limit 76 78 2.2 2.4 2.6 2.8 3 3.2 3.4 3.6 3.8 4 2.2 2.4 2.6 2.8 4.2 4.4 3 3.2 3.4 3.6 3.8 4 VBAT (V) VBAT (V) Adapter Insertion Battery Insertion/Removal VIN (5V/Div) VBAT (2V/Div) VLX (5V/Div) VLX (5V/Div) I IN (500mA/Div) IBAT (500mA/Div) VIN = 0V to 5V, VBAT = 3.5V Time (50ms/Div) 4.2 4.4 VIN = 5V, AICR = 500mA, VOREG = 4.44V Time (1s/Div) PWM Charging VLX (5V/Div) ILX (500mA/Div) VIN = 5V, VBAT = 2.6V, ICHRG = 1.25A Time (250ns/Div) Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9455-00 April 2014 is a registered trademark of Richtek Technology Corporation. www.richtek.com 11 RT9455 Boost Mode Efficiency vs. Load Current PWM Boost 100 90 Efficiency (%) 80 VBAT VBAT VBAT VBAT 70 60 = = = = 4.2V 3.9V 3.6V 3.3V VLX (5V/Div) 50 40 30 20 10 VIN = 5V I LOAD (500mA/Div) VBAT = 3.5V, ILOAD = 200mA 0 0 50 100 150 200 250 300 350 400 450 500 Time (250ns/Div) Load Current (mA) Time Constant for 32s Timer VIN Overload VIN (5V/Div) VIN (5V/Div) IRQ (2V/Div) IRQ (1V/Div) ILX (500mA/Div) I LOAD (500mA/Div) VBAT = 3.7V, ILOAD = 100mA VBAT = 3.7V, RL = 2Ω Time (5s/Div) Time (5ms/Div) Load Step Up Response Load Step Down Response V IN_ac (500mV/Div) V IN_ac (500mV/Div) VBAT_ac (200mV/Div) VBAT_ac (200mV/Div) VLX (5V/Div) VLX (5V/Div) I LOAD (200mA/Div) I LOAD (200mA/Div) VBAT = 3.8V, ILOAD = 0A to 200mA Time (100μs/Div) Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 12 VBAT = 3.8V, ILOAD = 0A to 200mA Time (100μs/Div) is a registered trademark of Richtek Technology Corporation. DS9455-00 April 2014 RT9455 Input Voltage vs. Load Current Input Voltage vs. VBAT 5.16 5.20 5.14 Input voltage (V) Input Voltage (V) 5.15 5.10 5.05 ILOAD = 50mA ILOAD = 100mA ILOAD = 200mA 5.00 5.12 5.10 5.08 VIN VIN VIN VIN 5.06 5.04 4.95 = = = = 3.3V 3.7V 4.1V 4.3V 5.02 VIN = 5V VIN = 5V 5.00 4.90 2.5 2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 VBAT (V) Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9455-00 April 2014 4.3 0 25 50 75 100 125 150 175 200 Load Current (mA) is a registered trademark of Richtek Technology Corporation. www.richtek.com 13 RT9455 Applications Information The RT9455 is an integrated solution of single-cell Li-ion and Li-polymer battery charger for portable applications. The part integrates a synchronous PWM controller with power MOSFETs to provide input voltage MIVR (Minimum Input Voltage Regulation), input current sensing, high accuracy current and voltage regulation, and charge termination in a small package for space limited devices. The part also features USB OTG (On-The-Go). The RT9455 has three operation modes : charge mode, boost mode (USB OTG), and high impedance mode. In charge mode, the RT9455 supports a precision charging system for single cell. In boost mode, the RT9455 works as the Boost converter and boosts the voltage from battery to VIN pin for sourcing the OTG devices. In high impedance mode, the RT9455 stops charging or boosting and operates in a mode with low current from VIN or battery to reduce the power consumption when the portable device is in standby mode. Start Notice that the RT9455 does not integrate input power source (AC adapter or USB input) detection. Thus, the RT9455 does not set the charge current automatically. The charge current needs to be set via I2C interface by the host. The RT9455 application mechanism and I2C compatible interface are introduced in later sections. The slave address for this device is “0100010”. I2C Interface Timing Diagram The RT9455 acts as an I2C -bus slave. The I2C -bus master configures the settings for charge mode and boost mode by sending command bytes to the RT9455 via the 2-wire I2C -bus. After the START condition, the I2C master sends a chip address. This address is seven bits long followed by an eighth bit which is a data direction bit (R/W). The second byte selects the register to which the data will be written. The third byte contains data to the selected register. The 1st Byte (Slave Address, R/W) The 2nd Byte (Data Address, Data) The 3rd Byte (Data) 0 1 0 0 0 1 0 R/W B7B6B5B4B3B2B1B0 C7C6C5C4C3C2C1C0 Stop S P SCL SDA 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 0 A6 A5 A4 A3 A2 A1 A0 W ACK B7 B6 B5 B4 B3 B2 B1 B0 ACK C7 C6 C5 C4 C3 C2 C1 C0 ACK S = Start Condition ACK = Acknowledge W = Write (SDA = “0”) P = Stop Condition R = Read (SDA = “1”) Charge Mode Operation Support Quick Start Feature of Charger When the battery voltage is lower than 2.4V by overdischarge condition, RT9455 charges the battery with 60mA to wake up the battery. Once the voltage level is higher than 2.4V, RT9455 charges the battery to higher level with large current and makes sure that the system could work normally in short period with OTG pin pulled high. Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 14 Minimum Input Voltage Regulation (MIVR) The RT9455 features input voltage MIVR function to prevent input voltage drop due to insufficient current provided by the adaptor or USB input. If MIVR function is enabled, the input voltage decreases when the over current of the input power source occurs and is regulated at a predetermined voltage level which can be set as 4V, 4.25V or 4.5V by I2C interface to MIVR[1:0] in the register of address 0x05 the CHMIVRI bit is set to high. At this time, the current drawn by the RT9455 equals to the maximum current value that the input power can provide at the predetermined voltage level, instead of the set value. The MIVR function is initially disabled. is a registered trademark of Richtek Technology Corporation. DS9455-00 April 2014 RT9455 Fast-Charge Mode and Settings VIN VIN MIVR Expected IIN Final IIN IIN As the BATS pin rises above VPREC, the charger enters fast-charge mode and starts switching. Notice that the RT9455 does not integrate input power source (AC adapter or USB input) detection. Thus, the RT9455 does not set the charge current automatically. Unlike the linear charger (LDO), the switching charger (Buck converter) is a current amplifier. The current drawn by the RT9455 is different from the current into the battery. The user can set the Average Input Current Regulation (AICR) and output charge current (ICHRG) respectively. set charge current Figure 1. Minimum Input Voltage Regulation (MIVR) Charge Profile The RT9455 provides a precision Li-ion or Li-polymer charging solution for single-cell applications. Input current limit, charge current, termination current, charge voltage and input voltage MIVR are all programmable via the I2C interface. In charge mode, the RT9455 has five control loops to regulate input current, charge current, charge voltage, input voltage MIVR and device junction temperature. During the charging process, all five loops (if MIVR is enabled) are enabled and the dominant one will take over the control. For normal charging process, the Li-ion or Li-polymer battery is charged in three charging modes depending on the battery voltage. At the beginning of the charging process, the RT9455 is in pre-charge mode. When the battery voltage rises above pre-charge threshold voltage (VPREC), the RT9455 enters fast-charge mode. Once the battery voltage is close to the regulation voltage (VOREG), the RT9455 enters constant voltage mode. Pre-Charge Mode For life-cycle consideration, the battery can not be charged with large current under low battery condition. When the BATS pin voltage is below pre-charge threshold voltage (VPREC), the charger is in pre-charge mode with a weak charge current which equals to the pre-charge current (IPREC). In pre-charge mode, the charger basically works as an LDO. The pre-charge current also acts as the current limit when the BATS pin is shorted. Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9455-00 April 2014 Cycle-by-Cycle Current Limit The charger of the RT9455 has an embedded cycle-bycycle current limit for inductor. Once the inductor current touches the threshold (2.5A typ.), the charger stops charging immediately to prevent over current from damaging the device. Notice that, the mechanism can not be disabled by any way. Average Input Current Regulation (AICR) The AICR setting is controlled by the AICR section (bit 7 and 6) in the register of address 0x01. The written value of “00” is for USB100 mode with the maximum current limit of 100mA, “01” is for USB 500 mode with the maximum current limit of 400mA and “10” is for the maximum current limit of 1000mA. If the application does not need input current limit, write “11” into the IINLIMIT section. Charge Current (ICHRG) The charge current into the battery is determined by the sense resistor (RSENSE) and ICHRG section (bit4, bit5, and bit6) in the register of address 0x06. The voltage between the ISENL and ISENR pins is regulated to the voltage control by ICHRG section. The charge current equals to the voltage between the ISENL and ISENR pins (VICHRG) divided by RSENSE : ICHRG = VICHRG RSENSE For example, for a 68mΩ sense resistor, the charge current can be set from 500mA (ICHRG [2:0] = 000) to 1550mA (ICHRG [2:0] = 111). is a registered trademark of Richtek Technology Corporation. www.richtek.com 15 RT9455 When input current limit and charge current are both set, the charge current in fast charge phase is calculated as below : V IIN_LIMIT ICHRG = MIN ICHRG , D RSENSE where D is the duty cycle and η is the efficiency. which can be selected in Sel_SWFreg section in the register of address 0x01. Frequency Reduction for Efficiency Improvement The switching frequency of the RT9455 is normally 1.5MHz. However, for improving efficiency, the RT9455 can also operate at 0.75MHz and 0.5MHz, which frequency are changed automatically depending on the energy demand. During the CC phase, the power flowing into the battery raises with the increased battery voltage. Hence, when battery voltage reaches the level, the switching frequency steps down to 0.75MHz/0.5MHz. Then, if the battery voltage keeps rising, the switching frequency will be decreased please make sure the inductor will not be saturated with a lager ripple current. Constant Voltage Mode and Settings The RT9455 enters constant voltage mode when the BATS voltage is close to the output-charge voltage (VOREG). Once in this mode, the charge current begins to decrease. For default settings (charge current termination is disabled), the RT9455 does not turn off and always regulates the battery voltage at VOREG. However, once the charge current termination is enabled, the charger terminates if the charge current is below termination current (IEOC) in constant voltage mode. The charge current termination function is controlled by the I2C interface in the “TE” bit via the register of address 0x01. After termination, a new charge cycle restarts when one of the following conditions is detected : Output Charge Voltage (VOREG) The output-charge voltage is set by the I2C interface in the CV section (Bit2 to Bit7 bits) via the register of address 0x02. Its range is from 3.5V to 4.45V. The default is 4V (011001). Termination Current (IEOC) If the end of charge detection and shutdown control for EOC are both enable (TE bit = “1”, TE_SHDN_EN bit = “1”), the end-of-charge current is determined by both the change current (I CHRG) and I EOC percentage. I EOC percentage is set by the I2C interface in the IEOC section via the register of address 0x05. Its range is from 10% to 30% with an step of 10%. The end-of-charge current is calculated as below : IEOC = ICHRG IEOC_percentage Safety Timer in Charge Mode and in OTG Mode To implement safety mechanism, the RT9455 has two timer modes : T32min mode with a 32-minute timer for charger mode and T32sec mode with a 32-second timer for OTG mode. In the charger mode, a the beginning of a charging operation, the RT9455 enters T32min mode and starts a 32-minute timer that can be reset by any read or write action performed by the host through the I2C interface. If the 32-minute timer expires, the charging operation is terminated and shows the fault bit CH32MI. In the OTG mode, at the beginning of a OTG operation, the RT9455 enters T32sec mode and starts a 32-second timer that can be reset by any read or write action performed by the host through the I2C interface. If the 32second timer expires, the OTG operation will keep going but shows the fault bit BST32SI. Input Voltage Protection in Charge Mode The BATS pin voltage falls below the VOREG − VRECH threshold. During charge mode, there are two protection mechanisms against poor input power source. VIN Power On Reset (POR). Sleep Mode (VIN − VBATS < VSLP) CEB bit toggle or RST bit is set (via I2C interface). The RT9455 enters sleep mode if the voltage drop between the VIN and BATS pins falls below VSLP. In sleep mode, Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 16 is a registered trademark of Richtek Technology Corporation. DS9455-00 April 2014 RT9455 the reverse blocking switch and PWM are all turned off. This function prevents battery drain during poor or no input power source. Input Over-Voltage Protection When VIN voltage rises above the input over-voltage threshold (VOVP_IN), the RT9455 stops charging and then sets fault status bits and sends out fault pulse via the STAT pin. The condition is released when VIN falls below VOVP_IN − ΔVOVP_IN. The RT9455 then resumes charging operation. Control Bits CHG_EN Bit (Charge Mode) The CHG_EN bit in control register of address 0x07 is used to disable or enable the charge process. A value of “0” disable the charge, while a value of “1” enable the charge. RST Bit The RST bit in control register of address 0x04 is used to reset the RT9455 back to its default value at power-up, regardless of its charging or boosting process. Boost Mode Operation (OTG) HZ (High Impedance Mode) Bit Trigger and Operation The RT9455 features USB OTG. When OTG function is enabled, the synchronous boost control loop takes over the power MOSFETs and reverses the power flow from the battery to the VIN pin. In normal boost mode, the MID pin is regulated to 5V (typ.) and provides up to 500mA current to support other USB OTG devices connected to the USB connector. Output Over-Voltage Protection In boost mode, the output over-voltage protection is triggered when the VIN voltage is above the output OVP threshold (6V typ.). When OVP occurs and the boost mode is triggered by the OTG pin, the RT9455 goes back to Boost Configure 1 state. When VIN returns to normal operating range, the condition is released and the boost resumes switching. However, if the boost mode is triggered by OPA bit, the RT9455 resets the OPA bit and goes back to Charge Configure state with default charge parameters. Output Overload Protection The RT9455 provides an overload protection to prevent the device and battery from damage when VIN is overload. Once overload condition is detected, the reverse blocking switch operates in linear region to limit the output current while the MID voltage remains in voltage regulation. If the overload condition lasts for more than 32ms, the RT9455 will recognise the overload fault condition and resets registers to the default settings. Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9455-00 April 2014 When the HZ bit is set to “1” and the OTG pin is not in active status, the RT9455 operates in high impedance mode. The condition is released by POR or setting the HZ bit to “0”. OPA Bit The OPA bit is the operation mode control bit, which is dependent on the status of HZ. OPA bit HZ bit 0 0 1 0 X 1 Operation Charge mode (no fault) Charge configure (fault, VIN > V UVLO) High impedance mode (VIN < VUVLO ) Boost mode (no fault) Go to charge configure when any fault High impedance mode Battery Protection Battery Over-Voltage Protection in Charge Mode The RT9455 monitors the BATS voltage for output overvoltage protection. In charge mode, if the BATS voltage rises above VOVP_BAT x VOREG, such as when the battery is suddenly removed, the RT9455 stops charging and then sets fault status bits and sends out fault pulse at the STAT pin. The condition is released when the BATS voltage falls below (VOVP_BAT − ΔVOVP_BAT) x VOVP_BAT. The RT9455 then resumes charging process with default settings and the fault is cleared. is a registered trademark of Richtek Technology Corporation. www.richtek.com 17 RT9455 Battery Detection During Normal Charging Thermal Considerations The RT9455 provides a battery absent detection scheme to detect insertion or removal of the battery pack. The battery detection scheme is valid only when the charge current termination is enabled (TE bit = “1”). For continuous operation, do not exceed absolute maximum junction temperature. The maximum power dissipation depends on the thermal resistance of the IC package, PCB layout, rate of surrounding airflow, and difference between junction and ambient temperature. The maximum power dissipation can be calculated by the following formula : I2C Setting Example The example below demonstrates the charge parameter setting of the RT9455 through the I2C interface. The component values follow that shown in typical application circuit. Charge Mode RSENSE = 68mΩ VIN MIVR = 4.25V Average Input Current Regulation, AICR = 1A Battery regulation voltage, VOREG = 4.2V Output Charge Current, ICHRG = 1.55A Termination Charge Current, IEOC = 10% PD(MAX) = (TJ(MAX) − TA) / θJA where TJ(MAX) is the maximum junction temperature, TA is the ambient temperature, and θJA is the junction to ambient thermal resistance. For recommended operating condition specifications, the maximum junction temperature is 125°C. The junction to ambient thermal resistance, θJA, is layout dependent. For WL-CSP-16B 1.7x1.77 (BSC) package, the thermal resistance, θJA, is 47.8°C/W on a standard JEDEC 51-7 four-layer thermal test board. The maximum power dissipation at TA = 25°C can be calculated by the following formula : PD(MAX) = (125°C − 25°C) / (47.8°C/W) = 2.09W for WL-CSP-16B 1.7x1.77 (BSC) package The maximum power dissipation depends on the operating ambient temperature for fixed T J(MAX) and thermal resistance, θJA. The derating curve in Figure 2 allows the designer to see the effect of rising ambient temperature on the maximum power dissipation. Maximum Power Dissipation (W)1 During normal charging process, once the charge done condition is satisfied (V BATS > V OREG − V RECH and termination current is detected), the RT9455 turns off the PWM converter and initiates a discharge current (detection current) for a detection time period. After that, the RT9455 checks the BATS voltage. If it is still above the recharge threshold, the battery is present and charge done is detected. If the BATS voltage is below the recharge threshold, the battery is absent. Thus, the RT9455 stops charging and the charge parameters are reset to the default values. The charge resumes after a period of tDET (2sec. typ.). 3.0 Four-Layer PCB 2.5 2.0 1.5 1.0 0.5 0.0 0 25 50 75 100 125 Ambient Temperature (°C) Figure 2. Derating Curve of Maximum Power Dissipation Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 18 is a registered trademark of Richtek Technology Corporation. DS9455-00 April 2014 RT9455 VIN MIVR and AICR Slave address Start 0 1 0 0 0 1 0 0 AICR 1A Data address 0x01 W 0 0 0 0 0 0 0 1 1 0 0 0 1 0 0 0 Stop Enable Termination Current VOREG Slave address Start 0 1 0 0 0 1 0 0 VOREG 4.2V Data address 0x02 W 0 0 0 0 0 0 1 0 1 0 0 0 1 1 1 0 Stop VIN MIVR, IEOC Slave address Start Start W Data address 0x05 0 1 0 0 0 1 0 0 0 0 0 0 0 1 0 1 Slave address Data address 0x06 W 0 1 0 0 0 1 0 0 IEOC 20% VIN MIVR 1 0 0 1 1 0 1 0 Stop ICHRG 0 0 0 0 0 1 1 0 0 1 1 1 0 0 1 0 Stop High Impedance Mode Slave address Start Data address 0x01 W 0 1 0 0 0 1 0 0 HZ 0 0 0 0 0 0 0 1 X X X X X X 1 X Stop Boost Mode There are two methods to trigger boost mode. I2C - Triggered Boost Mode Slave address Start 0 1 0 0 0 1 Data address 0x01 W 0 0 0 0 0 0 0 0 0 HZ OPA 1 X X X X X X 0 1 Stop OTG Pin - Triggered Boost Mode (Pull High or Pull Low) Pull Low Slave address Start W 0 1 0 0 0 1 0 0 OTG_EN Data address 0x02 0 0 0 0 0 0 1 0 X X X X X X 1 1 Stop OTG_PL Pull High Slave address Start W 0 1 0 0 0 1 0 0 OTG_EN Data address 0x02 0 0 0 0 0 0 1 0 X X X X X X 0 1 Stop OTG_PL Keep Monitoring RT9455 Slave address Start W 0 1 0 0 0 1 0 0 Data address 0x00 Charger Status 0 0 0 0 0 0 0 0 0 1 0 0 0 1 0 1 X X X X X X X X Stop < 32 min Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9455-00 April 2014 is a registered trademark of Richtek Technology Corporation. www.richtek.com 19 RT9455 Layout Considerations Place the input and output capacitors as close to the input and output pins as possible. The battery voltage sensing point should be placed after the output capacitor. Keep the main power traces as wide and short as possible. To optimize current sense accuracy, connect the traces to RSENSE with Kelvin sense connection. The output inductor and bootstrap capacitor should be placed close to the chip and LX pins. Place the input and output capacitors to the input and output pins as close as possible. To optimize current sense accuracy, Connect the traces to RSENSE with Kelvin sense connection. A1 A2 A3 A4 VIN VIN IRQ BATS B1 B2 B3 B4 VMID VMID OTG ISNSIN C1 C2 C3 C4 LX LX AGND SCL D1 D2 PGND PGND The output inductor and bootstrap capacitor should be placed close to the chip and the LX pins. D3 D4 BOOT SDA Keep the main power traces as wide and short as possible. Figure 3. PCB Layout Guide Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 20 is a registered trademark of Richtek Technology Corporation. DS9455-00 April 2014 RT9455 Device Address : 0100010 Address Name Bit7 Device ID 0x03 0x00 0x02 0x04 0x05 0x06 0x07 0x08 Bit5 Bit4 Bit3 VENDOR_ID Bit2 Bit1 Bit0 CHIP_REV Reset Value 0 0 0 0 1 0 0 1 Read/Write R R R R R R R R Control1 Reserved Reserved OTG_ PinP Reserved 0 1 0 0 0 0 0 0 R/W R/W R R R R R R TE_SHDN _EN Higher_ OCP TE IAICR_ INT HZ OPA_ MODE Reset Value Read/Write Control2 0x01 Bit6 Reset Value Read/Write Control3 Reset Value Read/Write IAICR[1:0] 0 0 0 0 0 0 0 R/W R/W R/W R/W R/W R/W R/W R/W VOREG[5:0] 1 1 0 0 1 1 0 R/W R/W R/W R/W R/W R/W R/W R/W Control5 Reset Value Read/Write Reserved Reserved Reserved Reserved Reserved Reserved Reserved 1 0 0 0 0 0 0 0 R/W R/W R/W R/W R/W R/W R/W R/W TMR_EN Reserved 1 0 1 1 1 0 1 0 R/W R/W R/W R/W R/W R/W R/W R/W Control6 IAICR_SEL Reset 0 Value Read/Write R/W MIVR[1:0] IPREC[1:0] ICHRG[2:0] Reserved IEOC[1:0] VPREC[2:0] 0 0 0 0 0 1 0 R/W R/W R/W R/W R/W R/W R/W Reserved BATD_EN Reserved CHG_EN VMREG[3:0] 0 0 0 1 0 0 0 0 R/W R/W R/W R/W R/W R/W R/W R/W TSDI VINOVPI 0 0 0 0 0 0 0 0 R R R R R R R R Reserved Reserved Reserved Reserved Reserved Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9455-00 April 2014 OTG_PL OTG_EN 0 RST IRQ1 Reset Value Read/Write BOOST PWR_Rdy 0 Control4 Reset Value Read/Write Control7 Reset Value Read/Write STAT BATAB is a registered trademark of Richtek Technology Corporation. www.richtek.com 21 RT9455 Address Name Bit7 CHRVPI 0x09 IRQ2 Reset Value Read/Write Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 Bit0 Reserved CHBATOVI CHTERMI CHRCHGI CH32MI CHTREGI CHMIVRI 0 0 0 0 0 0 0 0 R R R R R R R R 0x0A IRQ3 BSTVINOVI BSTOLI BSTLOWVI Reserved BST32SI Reserved Reserved Reserved Reset 0 0 0 0 0 0 0 0 Value Read/Write R R R R R R R R 0x0B Mask 1 Reset Value Read/Write Mask 2 0x0C Reset Value Read/Write Mask 3 0x0D Reset Value Read/Write TSDM VINOVPIM Reserved Reserved Reserved Reserved Reserved BATABM 0 0 R/W R/W 0 0 0 0 0 0 0 R/W R/W R/W R/W R/W R/W CHBATOVI CHTERMI CHRCHGI CHTREGI CHMIVRI CHRVPIM Reserved CH32MIM M M M M M 0 0 0 0 0 0 R/W R/W R/W R/W R/W R/W R/W R/W BSTVINOVI BSTLOWVI BST32SI BSTOLIM Reserved Reserved Reserved Reserved M M M 0 0 0 0 0 0 0 0 R/W R/W R/W R/W R/W R/W R/W R/W Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 22 0 is a registered trademark of Richtek Technology Corporation. DS9455-00 April 2014 RT9455 Detail Table Descriptions Address Name Bit7 Device ID 0x03 Bit4 Bit3 VENDOR_ID Bit2 Bit1 Bit0 CHIP_REV 0 0 0 0 1 0 0 1 Read/Write R R R R R R R R Bit5 Bit4 Bit3 Bit2 Bit1 Bit0 CHIP_REV Name Control1 0x00 Bit5 Reset Value VENDOR_ID Address Bit6 Vendor Identification Chip Revision Bit7 Bit6 Reserved Reserved STAT BOOST PWR_Rdy OTG_PinP Reserved Reset Value 0 1 0 0 0 0 0 0 Read/Write R/W R/W R R R R R R STAT BOOST Charger status bit 00 : Ready 01 : Charge in progress 10 : Charge done 11 : Fault 1 : Boost mode, 0 : Not in Boost mode PWR_Rdy Power status bit 0 : VIN > VOVP or VIN < VUVLO or VIN < BATS + VSLP (Power Fault) 1 : UVLO < VIN < VOVP & VIN > BATS + VSLP (Power Ready) OTG_PinP OTG pin polarity 0 : OTG input pin is low 1 : OTG input pin is high Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9455-00 April 2014 is a registered trademark of Richtek Technology Corporation. www.richtek.com 23 RT9455 Address Name Control2 0x01 Bit6 IAICR[1:0] Reset Value 0 1 Read/Write R/W R/W IAICR[1:0] TE_SHDN_EN Higher_OCP TE IAICR_INT HZ R/W R/W Bit3 Bit2 Bit1 Bit0 TE IAICR_INT HZ OPA_MODE 0 0 0 0 R/W R/W R/W R/W When IAICR_SEL = 0 00 : VIN 100mA current limit, 01 : VIN 500mA current limit, 10 : VIN 1A current limit, 11 : no input current limit (default 01) When IAICR_SEL = 1 00 : VIN 100mA current limit, 01 : VIN 700mA current limit, 10 : VIN 700mA current limit, 11 : no input current limit (default 01) 0 : When EOC is triggered, charge is not shutdown 1 : When EOC is triggered, charge is shutdown The OCP level selection bit 0 : Buck OCP = 2.75A, OTG OCP = 3.25A 1 : Buck OCP = 3.75A, OTG OCP = 4.25A 1 : Enable end of charge detection, 0 : Disable end of charge detection (default 0) IAICR setting bit 0 : decided by external OTG pin, 100mA current limit when OTG pin is low and 500mA current limit when OTG pin is high 2 1 : decided by internal I C IAICR[1:0] code Name 1 : Boost mode, 0 : Charger mode (default 0) Bit7 Bit6 Control3 0x02 Bit5 Bit4 TE_SHDN_ Higher_OCP EN 0 0 1 : High impedance mode, 0 : Not high impedance mode (default 0) OPA_MODE Address Bit7 Reset Value Read/Write Bit5 Bit4 Bit3 Bit2 VOREG[5:0] 0 1 1 0 0 1 Bit1 Bit0 OTG_PL OTG_EN 1 0 OTG_PL R/W R/W R/W R/W R/W R/W R/W R/W Battery regulation voltage / Boost output voltage. The delta-V of the Battery regulation voltage is 20mV. The delta-V of the Boost output voltage is 25mV. Only from 101000 to 101001, the delta-V is 30mV for battery regulation voltage. 00 0000 : 3.5V / 4.425V 00 0001 : 3.52V / 4.45V 00 0010 : 3.54V / 4.475V ... 01 1000 : 3.98V / 5.025V 01 1001 : 4V / 5.05V (default 011001) 01 1010 : 4.02V / 5.075V ... 10 1000 : 4.3V / 5.425V 10 1001 : 4.33V / 5.45V 10 1010 : 4.35V / 5.475V 10 1011 : 4.37V / 5.5V ... 10 1111 : 4.45V / 5.6V ... 11 1111 : 4.45V / 5.6V 1 : Active at High level, 0 : Active at low level (default 1) OTG_EN 1 : Enable OTG Pin, 0 : Disable OTG Pin (default 0) VOREG[5:0] Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 24 is a registered trademark of Richtek Technology Corporation. DS9455-00 April 2014 RT9455 Address 0x04 Name Bit7 Control4 RST Reset Value 0 0 0 0 0 0 0 0 Read/Write R/W R/W R/W R/W R/W R/W R/W R/W Bit1 Bit0 RST Address Name Control5 0x05 Bit6 Bit5 Bit2 Bit1 Bit0 Reserved Reserved Reserved Reserved Reserved Reserved Reserved Write 1 : Charger in reset mode, 0 : No effect, Read : always get "0" Bit7 Bit6 Bit5 TMR_EN Reserved Bit4 VMIVR[1:0] Bit3 Bit2 IPREC[1:0] IEOC[1:0] 1 0 1 1 1 0 1 0 Read/Write R/W R/W R/W R/W R/W R/W R/W R/W 0 : Disable internal timer function, 1 : Enable internal timer function (default 1) VMIVR[1:0] 00 : 4V 01 : 4.25V 10 : 4.5V 11 : disable (default 11) IPREC[1:0] 00 : 20mA 01 : 40mA 1X : 60mA (default 10) IEOC[1:0] 00 : 10% 01 : 30% 10 : 20% (default 10) 11 : 30% 0x06 Bit3 Reset Value TMR_EN Address Bit4 Name Bit7 IAICR_ Control6 SEL Reset Value 0 Bit6 0 0 0 0 0 1 0 Read/Write R/W R/W R/W R/W R/W R/W R/W R/W Bit5 Bit4 ICHRG[2:0] Bit3 Bit2 Reserved Bit1 Bit0 VPREC[2:0] IAICR_SEL 0 : AICR is defined by IAICR [1:0] 1: AICR 500mA and 1A becomes 700mA ICHRG[2:0] External Sensing R : Charge current sense voltage (current equivalent for 68m sense resistor) 000 : 34mV (500mA) (default 000) 001 : 44.2mV (650mA) 010 : 54.4mV (800mA) --110 : 95.2mV (1400mA) 111 : 105.4mV (1550mA) VPREC[2:0] 000 : 2V 001 : 2.2V 010 : 2.4V (default 010) 011 : 2.6V 100 : 2.8V 101 : 3V … 111 : 3V Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9455-00 April 2014 is a registered trademark of Richtek Technology Corporation. www.richtek.com 25 RT9455 Address Name Control 7 0x07 Bit7 Bit6 Bit5 Bit4 Bit3 Reserved BATD_EN Reserved CHG_EN 0 0 0 1 0 0 0 0 Read/Write R/W R/W R/W R/W R/W R/W R/W R/W CHG_EN Charger enable 0 : charger is disabled, 1 : charger is enabled VMREG[3:0] Bit7 IRQ 1 TSDI Reset Value 0 0 0 0 0 0 0 0 Read/Write R R R R R R R R VINOVPI BATAB Name IRQ 2 0x09 Maximum battery regulation voltage/Maximum Boost output voltage. The delta-V of Maximum battery regulation voltage is 20mV. The delta-V of Maximum Boost output voltage is 25mV. 0000 : 4.2V / 5.3V (Default 0000) 0001 : 4.22V / 5.325V 0010 : 4.24V / 5.35V ... 1011 : 4.43V / 5.575V 1100 : 4.45V / 5.6V … 1111 : 4.45V / 5.6V Name TSDI Address Bit0 Reset Value Battery detection when charge done 0 : disable battery detection, 1 : enable battery detection 0x08 Bit1 VMREG[3:0] BATD_EN Address Bit2 Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 VINOVPI Reserved Reserved Reserved Reserved Reserved Bit0 BATAB Thermal shutdown fault. Set if the die temperature exceeds the thermal shutdown threshold. When TSDI occurs, REG0 x 01[7:6]-AICR is reset to 01. VIN over voltage protection. Set when VIN > VIN_OVP is detected Battery absence Bit7 Bit6 Bit5 Bit4 Bit3 CHRVPI Reserved CHBATOVI CHTERMI CHRCHGI Bit2 CH32MI Bit1 Bit0 CHTREGI CHMIVRI Reset Value 0 0 0 0 0 0 0 0 Read/Write R R R R R R R R CHRVPI Charger fault. Reverse protection (VIN < BATS + VSLP) CHBATOVI Charger fault. Battery OVP CHTERMI Charge terminated CHRCHGI Recharge request (VBATS < VOREG VRECH) CH32MI Charger fault. 32m time-out (fault) CHTREGI Charger warning. Thermal regulation loop active. CHMIVRI Charger warning. Input voltage MIVR loop active. Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 26 is a registered trademark of Richtek Technology Corporation. DS9455-00 April 2014 RT9455 Address Name IRQ 3 0x0A Bit7 Bit6 Bit5 Bit0 BSTVINOVI BSTOLI BSTLOWVI Reserved BST32SI Reserved Reserved Reserved 0 0 0 0 0 0 Read/Write R R R R R R R R Bit3 Bit2 Bit1 Bit0 Boost fault. VIN OVP (VIN > VIN_BOVP) Boost fault. Over load. Boost fault. Battery voltage is too low. BST32SI Boost fault. 32s time-out fault. Reserved N/A Reserved N/A Reserved N/A Name Bit7 Bit6 Bit5 Bit4 MASK1 TSDM Reset Value 0 0 0 0 0 0 0 0 Read/Write R/W R/W R R R R R/W R/W VINOVPIM Reserved Reserved Reserved Reserved Reserved TSDM TSDI fault interrupt mask 0 : interrupt is not masked, 1 : interrupt is masked VINOVPIM VIN OVP fault interrupt mask 0 : interrupt is not masked, 1 : interrupt is masked BATABM Battery absence fault interrupt mask 0 : interrupt is not masked, 1 : interrupt is masked 0x0C Bit1 0 BSTLOWVI Address Bit2 0 BSTOLI 0x0B Bit3 Reset Value BSTBUSOVI Address Bit4 Name Bit7 Bit6 Read/Write R/W R/W BATABM Bit5 Bit4 Bit3 Bit2 Bit1 Bit0 CHBATO MASK2 CHRVPIM Reserved CHTERMIM CHRCHGIM CH32MIM CHTREGIM CHMIVRM VIM Reset Value 0 0 0 0 0 0 0 0 R/W R/W R/W CHRVPIM Charger reverse protection interrupt mask 0 : interrupt is not masked, 1 : interrupt is masked CHBATOVIM Charger battery over voltage interrupt mask 0 : interrupt is not masked, 1 : interrupt is masked CHTERMIM Charge terminated interrupt mask 0 : interrupt is not masked, 1 : interrupt is masked CHRCHGIM Charger recharge request interrupt mask 0 : interrupt is not masked, 1 : interrupt is masked CH32MIM Charger 32m timeout interrupt mask 0 : interrupt is not masked, 1 : interrupt is masked CHTREGIM Charger thermal regulation loop active interrupt mask 0 : interrupt is not masked, 1 : interrupt is masked CHMIVRM Charger input current voltage MIVR active interrupt mask 0 : interrupt is not masked, 1 : interrupt is masked Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9455-00 April 2014 R/W R/W R/W is a registered trademark of Richtek Technology Corporation. www.richtek.com 27 RT9455 Address 0x0D Name Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 Bit0 BSTLOW BSTVINO Reserved BST32SIM Reserved Reserved Reserved BSTOLIM MASK3 VIM VIM Reset Value 0 0 0 0 0 0 0 0 Read/Write R/W R/W R/W R/W BSTVINOVIM Boost VIN over voltage interrupt mask 0 : interrupt is not masked, 1 : interrupt is masked BSTOLIM Boost over load interrupt mask 0 : interrupt is not masked, 1 : interrupt is masked BSTLOWVIM Boost low battery voltage interrupt mask 0 : interrupt is not masked, 1 : interrupt is masked BST32SIM Boost 32s time out interrupt mask 0 : interrupt is not masked, 1 : interrupt is masked Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 28 R/W R/W R/W R/W is a registered trademark of Richtek Technology Corporation. DS9455-00 April 2014 RT9455 Outline Dimension Symbol Dimensions In Millimeters Dimensions In Inches Min. Max. Min. Max. A 0.500 0.600 0.020 0.024 A1 0.170 0.230 0.007 0.009 b 0.240 0.300 0.009 0.012 D 1.720 1.820 0.068 0.072 D1 E 1.200 1.650 0.047 1.750 0.065 0.069 E1 1.200 0.047 e 0.400 0.016 16B WL-CSP 1.7x1.77 Package (BSC) Richtek Technology Corporation 14F, No. 8, Tai Yuen 1st Street, Chupei City Hsinchu, Taiwan, R.O.C. Tel: (8863)5526789 Richtek products are sold by description only. Richtek reserves the right to change the circuitry and/or specifications without notice at any time. Customers should obtain the latest relevant information and data sheets before placing orders and should verify that such information is current and complete. Richtek cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Richtek product. Information furnished by Richtek is believed to be accurate and reliable. However, no responsibility is assumed by Richtek or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Richtek or its subsidiaries. DS9455-00 April 2014 www.richtek.com 29