BQ51013ARHLT

bq51014 is Not Recommended For New Designs bq51013A bq51014 www.ti.com SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 INTEGRATED WIRELESS POWER SUPPLY RECEIVER, Qi (WIRELESS POWER CONSORTIUM) COMPLIANT Check for Samples: bq51013A, bq51014 FEATURES 1 • • • • • • • • • • • Integrated Wireless Power Receiver Solution with a 5V Regulated Supply – 93% Overall Peak AC-DC Efficiency – Full Synchronous Rectifier – WPC v1.0 Compliant Communication Control – Output Voltage Conditioning – Only IC Required Between RX coil and 5V DC Output Voltage Dynamic Rectifier Control for Improved Load Transient Response Dynamic Efficiency Scaling for Optimized Performance Over any Range of Output Power Adaptive Communication Limit for Robust Communication During High Levels of Load Current Noise Supports 20-V Maximum Input Low-power Dissipative Rectifier Overvoltage Clamp (VOVP = 15V) Thermal Shutdown Multifunction NTC and Control Pin for Temperature Monitoring, Done Charging and Fault Host Control Stand-alone Digital Controller Programmable Termination Pin for Charge Status 100% (CS100) Support 1.9 x 3mm DSBG or 4.5 x 3.5mm QFN Package APPLICATIONS • • • • • • WPC Compliant Receivers Cell Phones, Smart Phones Headsets Digital Cameras Portable Media Players Hand-held Devices DESCRIPTION The bq5101x is an advanced, integrated, receiver IC for wireless power transfer in portable applications. The device provides the AC/DC power conversion while integrating the digital control required to comply with the Qi v1.0 communication protocol. Together with the bq500210 transmitter controller, the bq5101x enables a complete contact-less power transfer system for a wireless power supply solution. By using near-field inductive power transfer, the receiver coil embedded in the portable device receives the power transmitted by the transmitter coil via mutually coupled inductors. The AC signal from the receiver coil is then rectified and regulated to be used as a power supply for down-system electronics. Global feedback is established from the secondary to the transmitter in order to stabilize the power transfer process via back-scatter modulation. This feedback is established by using the Qi v1.0 communication protocol supporting up to 5 W applications. The device integrates a low-impedance full synchronous rectifier, low-dropout regulator, digital control, and accurate voltage and current loops. The entire power stage (rectifier and LDO) use low resistive NMOS FET’s to ensures high efficiency and low power dissipation. Power AC to DC Drivers bq5101x Rectification Voltage Conditioning Load Communication V/I Sense Controller Controller bq500210 Transmitter Receiver Figure 1. Wireless Power Consortium (WPC or Qi) Inductive Power System 1 Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. Copyright © 2012–2013, Texas Instruments Incorporated bq51014 is Not Recommended For New Designs bq51013A bq51014 SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 www.ti.com These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates. ORDERING INFORMATION Part NO Marking Function Package DSBGA-YFP bq51013A bq51013A 5V Regulated Power Supply QFN-RHL bq51014 bq51014 5V Regulated Power Supply Ordering Number (Tape and Reel) Quantity bq51013AYFPR 3000 bq51013AYFPT 250 bq51013ARHLR 3000 bq51013ARHLT 250 bq51014YFPR 3000 bq51014YFPT 250 DSBGA-YFP AVAILABLE OPTIONS WPC Version Device Function bq51013A 5V Power Supply v1.0 15V bq51014 5V Power Supply v1.0 15V (1) (2) VRECT-OVP Over Current Shutdown AD-OVP 5V Disabled Disabled Disabled Tracking + 1s HoldOff 5V Enabled 12.5V Enabled Tracking + 1s HoldOff VOUT-(REG) Termination (CS100) Communication Current Limit (1) (2) Enabled if EN2 is low and disabled if EN2 is high Communication current limit is disabled for 1 second at startup ABSOLUTE MAXIMUM RATINGS (1) (2) over operating free-air temperature range (unless otherwise noted) PARAMETER Input Voltage VALUES PIN UNITS MIN MAX AC1, AC2 –0.8 20 RECT, COM1, COM2, OUT, CHG, CLAMP1, CLAMP2 –0.3 20 AD, AD-EN –0.3 30 V BOOT1, BOOT2 –0.3 26 V EN1, EN2, TERM, FOD, TS-CTRL, ILIM –0.3 7 V 2 A(RMS) V V Input Current AC1, AC2 Output Current OUT 1.5 A CHG 15 mA COM1, COM2 1 A °C Output Sink Current Junction temperature, TJ -40 150 Storage temperature, TSTG –65 150 ESD Rating (HBM) (100pF, 1.5KΩ) (1) (2) 2 All 2 °C kV All voltages are with respect to the VSS terminal, unless otherwise noted. Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under recommended operating conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 bq51014 is Not Recommended For New Designs bq51013A bq51014 www.ti.com SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 THERMAL INFORMATION THERMAL METRIC (1) RHL YFP 20 PiNS 28 PINS θJA Junction-to-ambient thermal resistance 37.7 58.9 θJCtop Junction-to-case (top) thermal resistance 35.5 0.2 θJB Junction-to-board thermal resistance 13.6 9.1 ψJT Junction-to-top characterization parameter 0.5 1.4 ψJB Junction-to-board characterization parameter 13.5 8.9 θJCbot Junction-to-case (bottom) thermal resistance 2.7 n/a (1) UNITS °C/W For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953. RECOMMENDED OPERATING CONDITIONS over operating free-air temperature range (unless otherwise noted) PINS MIN MAX UNITS Input voltage range, VIN PARAMETER RECT 4 10 V Input current, IIN RECT 1.5 A Output current, IOUT OUT 1.5 A Sink current, IAD-EN AD-EN 1 mA COMM sink current, ICOMM COMM 500 mA 125 ºC Junction Temperature, TJ 0 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 3 bq51014 is Not Recommended For New Designs bq51013A bq51014 SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 www.ti.com TYPICAL APPLICATION SCHEMATICS bq5101x System Load AD-EN AD OUT C COMM1 C4 COMM1 CBOOT1 D1 BOOT1 RECT C1 AC1 C3 COIL R4 HOST C2 TS-CTRL AC2 NTC BOOT2 CBOOT2 COMM2 CHG CCOMM2 C CLAMP2 CCLAMP1 3 - State CLAMP2 EN1 or TERM Bi-State CLAMP1 EN2 Bi-State FOD ILIM R1 PGND R TERM (bq51014) 140Ω Figure 2. bq5101x Used as a Wireless Power Receiver and Power Supply for System Loads 4 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 bq51014 is Not Recommended For New Designs bq51013A bq51014 www.ti.com SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 System Load Q1 USB or AC Adapter Input D2 (bq51014) bq5101x AD-EN AD OUT C COMM1 C4 COMM1 C5 C BOOT1 D1 BOOT1 RECT C1 AC1 C3 COIL R4 C2 TS-CTRL AC2 NTC BOOT2 C BOOT2 HOST COMM2 CHG CCOMM2 CCLAMP2 C CLAMP1 Tri-State CLAMP2 EN1 or TERM Bi-State CLAMP1 EN2 Bi-State ILIM R1 FOD PGND RTERM (bq51014) 140Ω Figure 3. bq5101x Used as a Wireless Power Receiver and Power Supply for System Loads With Adapter Power-Path Multiplexing Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 5 bq51014 is Not Recommended For New Designs bq51013A bq51014 SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 www.ti.com ELECTRICAL CHARACTERISTICS over operating free-air temperature range, –40°C to 125°C (unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX 2.7 2.8 Undervoltage lock-out VRECT: 0V → 3V Hysteresis on UVLO VRECT: 3V → 2V Hysteresis on OVP VRECT: 16V → 5V Input overvoltage threshold VRECT: 5V → 16V Dynamic VRECT Threshold 1 ILOAD < 0.1 x IILIM (ILOAD rising) 7.08 Dynamic VRECT Threshold 2 0.1 x IILIM < ILOAD < 0.2 x IILIM (ILOAD rising) 6.28 Dynamic VRECT Threshold 3 0.2 x IILIM < ILOAD < 0.4 x IILIM (ILOAD rising) 5.53 Dynamic VRECT Threshold 4 ILOAD > 0.4 x IILIM (ILOAD rising) 5.11 ILOAD ILOAD Hysteresis for dynamic VRECT thresholds as a % of IILIM ILOAD falling VRECT-DPM Rectifier undervoltage protection, restricts IOUT at VRECT-DPM VRECT-REV Rectifier reverse voltage protection at the output UVLO VHYS VRECT VRECT-REG 2.5 250 15 V mV 150 14.5 UNIT mV 15.5 V V 4% 3 3.1 3.2 V VRECT-REV = VOUT - VRECT, VOUT = 10V 8 9 V ILOAD = 0 mA, 0°C ≤ TJ ≤ 85°C 8 10 mA ILOAD = 300 mA, 0°C ≤ TJ ≤ 85°C 2 3.0 mA VOUT = 5 V, 0°C ≤ TJ ≤ 85°C 20 35 µA 120 Ω Quiescent Current IRECT Active chip quiescent current consumption from RECT IOUT Quiescent current at the output when wireless power is disabled (Standby) ILIM Short Circuit RILIM Highest value of ILIM resistor considered a fault (short). Monitored for IOUT > 100 mA tDGL Deglitch time transition from ILIM short to IOUT disable ILIM_SC IOUT RILIM: 200Ω → 50Ω. IOUT latches off, cycle power to reset 1 ILIM-SHORT,OK enables the ILIM short comparator when IOUT is greater than this value ILOAD: 0 → 20 0mA Hysteresis for ILIM-SHORT,OK comparator ILOAD: 0 → 200 mA Maximum output current limit, CL Maximum ILOAD that will be delivered for 1 ms when ILIM is shorted 120 145 ms 165 30 mA mA 2.4 A OUTPUT ILOAD = 1000 mA 4.82 4.95 5 ILOAD = 10 mA 4.92 5 5.05 RLIM = KILIM / IILIM, where IILIM is the hardware current limit. IOUT =1A 280 300 320 230 250 270 VOUT-REG Regulated output voltage KILIM Current programming factor for hardware short circuit protection KIMAX IIMAX = KIMAX / RLIM where IMAX Current programming factor for the nominal is the maximum normal operating current operating current. IOUT = 1 A IOUT Current limit programming range ICOMM Current limit during WPC communication tHOLD Hold off time for the communication current limit during startup 6 AΩ AΩ 1500 IOUT > 300 mA IOUT < 300 mA Submit Documentation Feedback V IOUT + 50 350 390 1 mA mA 435 mA s Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 bq51014 is Not Recommended For New Designs bq51013A bq51014 www.ti.com SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 ELECTRICAL CHARACTERISTICS (continued) over operating free-air temperature range, –40°C to 125°C (unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX UNIT Programmable termination factor as a percentage of IMAX RTERM = %IMAX x KTERM 160 200 240 Ω/% High termination current threshold calculation ITERM-HI = (RTERM / KTERM) x 0.01 x IMAX, where IMAX = KIMAX / RILIM TERMINATION (Charge Status 100%) – bq51014 ONLY KTERM ITERM tTERM Low termination current threshold 25 Constant current at the TERM pin to bias the termination resistor VTERM = 0 V High termination threshold deglitch ITERM-LOW< IOUT < ITERM-HI High termination threshold deglitch IOUT < ITERM-LOW Internal TS Bias Voltage ITS-Bias < 100 µA (periodically driven see tTS-CTRL) Rising threshold VTS: 50% → 60% Falling hysteresis VTS: 60% → 50% Falling threshold VTS: 20% → 15% Rising hysteresis VTS: 15% → 20% CTRL pin threshold for a high 48 51 mA 54 µA 180 sec 7 sec TS / CTRL VTS 2 2.2 2.4 56.5 58.7 60.8 18.5 19.6 VTS/CTRL: 50 → 150mV 80 100 130 mV CTRL pin threshold for a low VTS/CTRL: 150 → 50mV 50 80 100 mV tTS-CTRL Time VTS-Bias is active when TS measurements occur Synchronous to the communication period tTS Deglitch time for all TS comparators RTS Pull-up resistor for the NTC network. Pulled up to the voltage bias VCOLD VHOT VCTRL 1 20.7 V %VTS-Bias 1 18 24 ms 10 ms 20 22 kΩ THERMAL PROTECTION TJ Thermal shutdown temperature Thermal shutdown hysteresis 155 °C 20 °C OUTPUT LOGIC LEVELS ON WPG VOL Open drain WPG pin ISINK = 5 mA 500 mV IOFF WPG leakage current when disabled VCHG = 20 V 1 µA RDS(ON) COM1 and COM2 VRECT = 2.6 V fCOMM Signaling frequency on COMM pin IOFF Comm pin leakage current COMM PIN 1.5 Ω 2.00 Kb/s VCOM1 = 20 V, VCOM2 = 20 V 1 µA CLAMP PIN RDS(ON) Clamp1 and Clamp2 Ω 1 Adapter Enable VAD-EN VAD Rising threshold voltage. EN-UVLO VAD 0 → 5 V VAD-EN hysteresis, EN-HYS VAD 5 → 0 V IAD Input leakage current VRECT = 0V, VAD = 5V VAD-OVP Adapter mode OVP threshold rising edge VAD-OVP hysteresis bq51014 VAD 10 → 15 V 3.5 RAD VAD Voltage difference between VAD and VAD-EN VAD = 5 V, 0°C ≤ TJ ≤ 85°C when adapter mode is enabled, EN-ON 3.8 400 12 VAD 15 → 10 V Pull-up resistance from AD-EN to OUT when adapter mode is disabled and VOUT > VAD = 0, VOUT = 5 VAD, EN-OUT 3.6 12.5 mV 60 μA 13 V 0.5 3 V 200 350 Ω 4.5 5 V Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 V 7 bq51014 is Not Recommended For New Designs bq51013A bq51014 SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 www.ti.com ELECTRICAL CHARACTERISTICS (continued) over operating free-air temperature range, –40°C to 125°C (unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX UNIT 80 100 125 mA Synchronous Rectifier IOUT VHS-DIODE IOUT at which the synchronous rectifier enters half synchronous mode, SYNC_EN ILOAD 200 → 0 mA Hysteresis for IOUT,RECT-EN (fullsynchronous mode enabled) ILOAD 0 → 200 mA High-side diode drop when the rectifier is in IAC-VRECT = 250 mA and TJ = half synchronous mode 25°C 25 mA 0.7 V EN1 and EN2 VIL Input low threshold for EN1 and EN2 VIH Input high threshold for EN1 and EN2 RPD EN1 and EN2 pull down resistance 0.4 1.3 V V 200 kΩ ±6 % ADC (WPC Related Measurements and Coefficients) PRECT 8 Rectified power accuracy as a percentage of output power 0W – 5W of rectified power Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 bq51014 is Not Recommended For New Designs bq51013A bq51014 www.ti.com SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 DEVICE INFORMATION SIMPLIFIED BLOCK DIAGRAM RECT M1 I OUT VOUT,FB + _ + _ VREF,ILIM VILIM VOUT,REG VREF,IABS VIABS,FB + _ VIN,FB VIN,DPM + _ ILIM AD + _ VREFAD,OVP BOOT2 + _ BOOT1 VREFAD,UVLO AD-EN AC1 AC2 Sync Rectifier Control VREF,TS-BIAS COMM1 COMM2 DATA _ OUT CLAMP1 ADC Digital Control TS_COLD VBG,REF VIN,FB VOUT,FB VILIM VIABS,FB VIABS,REF VIC,TEMP CLAMP2 VFOD + _ TS_HOT FOD + _ + _ TS-CTRL TS_DETECT + _ VREF_100MV VFOD 50uA + _ CHG ILIM 200kW VRECT VOVP,REF + _ OVP EN1 or TERM EN2 200kW PGND Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 9 bq51014 is Not Recommended For New Designs bq51013A bq51014 SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 www.ti.com YFP Package (TOP VIEW) RHL Package (TOP VIEW) PGND 1 A1 PGND A2 PGND A3 PGND A4 PGND B1 AC2 B2 AC2 B3 AC1 B4 AC1 C1 BOOT2 C2 RECT C3 RECT C4 BOOT1 D1 OUT D2 OUT D3 OUT PGND 20 AC1 2 AC2 19 BOOT1 3 RECT 18 OUT 4 BOOT2 17 CLMP1 5 CLMP2 16 COM1 6 COM2 15 CHG 7 FOD 14 AD-EN 8 TSCTRL 13 AD 9 ILIM 12 D4 OUT E1 COM2 E2 CLMP2 E3 CLMP1 E4 COM1 F1 TS-CTRL F2 FOD F3 /AD-EN F4 /CHG G1 ILIM G2 EN2 G3 G4 AD EN1 or TERM EN1or TERM 10 EN2 11 PIN FUNCTIONS NAME YFP RHL AC1 B3, B4 2 I AC2 B1, B2 19 I BOOT1 C4 3 O BOOT2 C1 17 O RECT C2, C3 18 O Filter capacitor for the internal synchronous rectifier. Connect a ceramic capacitor to PGND. Depending on the power levels, the value may be 4.7 μF to 22 μF. OUT D1, D2, D3, D4 4 O Output pin, delivers power to the load. O Open-drain output used to communicate with primary by varying reflected impedance. Connect through a capacitor to either AC1 or AC2 for capacitive load modulation (COM2 must be connected to the alternate AC1 or AC2 pin). For resistive modulation connect COM1 and COM2 to RECT via a single resistor; connect through separate capacitors for capacitive load modulation. Open-drain output used to communicate with primary by varying reflected impedance. Connect through a capacitor to either AC1 or AC2 for capacitive load modulation (COM1 must be connected to the alternate AC1 or AC2 pin). For resistive modulation connect COM1 and COM2 to RECT via a single resistor; connect through separate capacitors for capacitive load modulation. COM1 E4 6 I/O AC input from receiver coil antenna. COM2 E1 15 O CLMP2 E2 16 O CLMP1 E3 5 O PGND A1, A2, A3, A4 1, 20 10 DESCRIPTION Bootstrap capacitors for driving the high-side FETs of the synchronous rectifier. Connect a 10 nF ceramic capacitor from BOOT1 to AC1 and from BOOT2 to AC2. Open drain FETs which are utilized for a non-power dissipative over-voltage AC clamp protection. When the RECT voltage goes above 15 V, both switches will be turned on and the capacitors will act as a low impedance to protect the IC from damage. If used, Clamp1 is required to be connected to AC1, and Clamp2 is required to be connected to AC2 via 0.47µF capacitors. Power ground Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 bq51014 is Not Recommended For New Designs bq51013A bq51014 www.ti.com SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 PIN FUNCTIONS (continued) NAME YFP ILIM RHL G1 12 I/O DESCRIPTION I/O Programming pin for the over current limit. Connect external resistor to VSS. Size RILIM with the following equation: RILIM = 250 / IMAX where IMAX is the expected maximum output current of the wireless power supply. The hardware current limit (IILIM) will be 20% greater than IMAX or 1.2 x 1MAX. If the supply is meant to operate in current limit use RILIM = 300 / IILIM RILIM = R1 + 140 AD G4 9 I Connect this pin to the wired adapter input. When a voltage is applied to this pin wireless charging is disabled and AD_EN is driven low. Connect to GND through a 1 µF capacitor. If unused, capacitor is not required and should be grounded directly. For the bq51014, there is an OVP protection of 12.5 V. If the AD voltage is greater than 12.5 V, wireless charging will remain active. AD-EN F3 8 O Push-pull driver for external PFET connecting AD and OUT. This node is pulled to the higher of OUT and AD when turning off the external FET. This voltage tracks approximately 4 V below AD when voltage is present at AD and provides a regulated VSG bias for the external FET. Float this pin if unused. Must be connected to ground via a resistor. If an NTC function is not desired connect to GND with a 10 kΩ resistor. As a CTRL pin pull to ground to send end power transfer (EPT) fault to the transmitter or pull-up to an internal rail (i.e. 1.8 V) to send EPT termination to the transmitter. Note that a 3-state driver should be used to interface this pin (see the 3-state Driver section for further description) TS-CTRL F1 13 I EN1 G3 10 I EN2 G2 11 I TERM G3 10 I Input that allows allows the upper termination threshold (ITERM-HI) to be programmable. KTERM = 200 Ω/%. Set the termination threshold by applying the following equation RTERM = %IMAX x KTERM where %IMAX is the desired percentage of the maximum output current when termination should occur (i.e. 10% of 1 A = 0.1 mA) FOD F2 14 O Input for the rectified power measurement. Connect to GND with a 140 Ω resistor CHG F4 7 O Open-drain output – active when output current is being delivered to the load (i.e. when the output of the supply is enabled). Inputs that allow user to enable/disable wireless and wired charging : wireless charging is enabled unless AD voltage > 3.6 V Dynamic communication current limit disabled AD-EN pulled low, wireless charging disabled wired and wireless charging disabled. Spacer TYPICAL CHARACTERISTICS 100.0 100.0 90.0 90.0 Efficiency (%) Efficiency (%) Full Sync Mode Enabled 80.0 80.0 70.0 60.0 0.0 1.0 2.0 3.0 4.0 Output Power (W) 5.0 Figure 4. Rectifier Efficiency 6.0 70.0 1.0 2.0 3.0 Output Power (W) 4.0 5.0 Figure 5. IC Efficiency from AC Input to DC Output Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 11 bq51014 is Not Recommended For New Designs bq51013A bq51014 SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 www.ti.com TYPICAL CHARACTERISTICS (continued) Rising Falling 70 300 mA) Figure 27. Rx Communication Packet Structure (1) Efficiency measured from DC input to the transmitter to DC output of the receiver. Transmitter was the bq500210 EVM. Measurement subject to change if an alternate transmitter is used. (2) Curves illustrates the resulting ILIM current by sweeping the output voltage at different RILIM settings. ILIM current collapses due to the increasing power dissipation as the voltage at the output is decreased—thermal shutdown is occurring. (3) Total droop experienced at the output is dependent on receiver coil design. The output impedance must be low enough at that particular operating frequency in order to not collapse the rectifier below 5V. (4) On the go mode is enabled by driving EN1 high. In this test the external PMOS is connected between the output of the bq5101x IC and the AD pin; therefore, any voltage source on the output is supplied to the AD pin. 16 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 bq51014 is Not Recommended For New Designs bq51013A bq51014 www.ti.com SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 PRINCIPLE OF OPERATION Power AC to DC bq5101x Drivers Rectification Voltage Conditioning Load Communication Controller V/I Sense Controller bq500210 Transmitter Receiver Figure 28. WPC Wireless Power System Indicating the Functional Integration of the bq5101x A Brief Description of the Wireless System: A wireless system consists of a charging pad (transmitter or primary) and the secondary-side equipment (receiver or secondary). There is a coil in the charging pad and in the secondary equipment which are magnetically coupled to each other when the secondary is placed on the primary. Power is then transferred from the transmitter to the receiver via coupled inductors (e.g. an air-core transformer). Controlling the amount of power transferred is achieved by sending feedback (error signal) communication to the primary (e.g. to increase or decrease power). The receiver communicates with the transmitter by changing the load seen by the transmitter. This load variation results in a change in the transmitter coil current, which is measured and interpreted by a processor in the charging pad. The communication is digital - packets are transferred from the receiver to the transmitter. Differential Bi-phase encoding is used for the packets. The bit rate is 2-kbps. Various types of communication packets have been defined. These include identification and authentication packets, error packets, control packets, end power packets, and power usage packets. The transmitter coil stays powered off most of the time. It occasionally wakes up to see if a receiver is present. When a receiver authenticates itself to the transmitter, the transmiter will remain powered on. The receiver maintains full control over the power transfer using communication packets. Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 17 bq51014 is Not Recommended For New Designs bq51013A bq51014 SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 www.ti.com Using the bq5101x as a Wireless Power Supply: (See Figure 3) Figure 3 is the schematic of a system which uses the bq5101x as power supply while power multiplexing the wired (adapter) port. When the system shown in Figure 3 is placed on the charging pad, the receiver coil is inductively coupled to the magnetic flux generated by the coil in the charging pad which consequently induces a voltage in the receiver coil. The internal synchronous rectifier feeds this voltage to the RECT pin which has the filter capacitor C3. The bq5101x identifies and authenticates itself to the primary using the COM pins by switching on and off the COM FETs and hence switching in and out CCOMM. If the authentication is successful, the transmitter will remain powered on. The bq5101x measures the voltage at the RECT pin, calculates the difference between the actual voltage and the desired voltage VRECT-REG, (threshold 1 at no load) and sends back error packets to the primary. This process goes on until the input voltage settles at VRECT-REG. During a load transient, the dynamic rectifier algorithm will set the targets specified by VRECT-REG thresholds 1, 2, 3, and 4. This algorithm is termed Dynamic Rectifier Control and is used to enhance the transient response of the power supply. During power-up, the LDO is held off until the VRECT-REG threshold 1 converges. The voltage control loop ensures that the output voltage is maintained at VOUT-REG to power the system. The bq5101x meanwhile continues to monitor the input voltage, and maintains sending error packets to the primary every 250ms. If a large transient occurs, the feedback to the primary speeds up to every 32ms in order to converge on an operating point in less time. Details of a Qi Wireless Power System and bq5101x Power Transfer Flow Diagrams The bq5101x family integrates a fully compliant WPC v1.0 communication algorithm in order to streamline receiver designs (no extra software development required). Other unique algorithms such has Dynamic Rectifier Control are also integrated to provide best in class system performance. This section provides a high level overview of these features by illustrating the wireless power transfer flow diagram from startup to active operation. During startup operation, the wireless power receiver must comply with proper handshaking to be granted a power contract from the Tx. The Tx will initiate the hand shake by providing an extended digital ping. If an Rx is present on the Tx surface, the Rx will then provide the signal strength, configuration and identification packets to the Tx (see volume 1 of the WPC specification for details on each packet). These are the first three packets sent to the Tx. The only exception is if there is a true shutdown condition on the EN1/EN2, AD, or TS-CTRL pins where the Rx will shut down the Tx immediately. See Table 4 for details. Once the Tx has successfully received the signal strength, configuration and identification packets, the Rx will be granted a power contract and is then allowed to control the operating point of the power transfer. With the use of the bq5101x Dynamic Rectifier Control algorithm, the Rx will inform the Tx to adjust the rectifier voltage above 7 V prior to enabling the output supply. This method enhances the transient performance during system startup. See Figure 29 for the startup flow diagram details. 18 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 bq51014 is Not Recommended For New Designs bq51013A bq51014 www.ti.com SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 Tx Powered without Rx Active Tx Extended Digital Ping EN1/EN2/AD/TS-CTRL EPT Condition? Yes Send EPT packet with reason value No Identification and Configuration and SS, Received by Tx? No Yes Power Contract Established. All proceeding control is dictated by the Rx. Yes VRECT < 7V? Send control error packet to increase VRECT No Startup operating point established. Enable the Rx output. Rx Active Power Transfer Stage Figure 29. Wireless Power Startup Flow Diagram Once the startup procedure has been established, the Rx will enter the active power transfer stage. This is considered the “main loop” of operation. The Dynamic Rectifier Control algorithm will determine the rectifier voltage target based on a percentage of the maximum output current level setting (set by KIMAX and the ILIM resistance to GND). The Rx will send control error packets in order to converge on these targets. As the output current changes, the rectifier voltage target will dynamically change. As a note, the feedback loop of the WPC system is relatively slow where it can take up to 90 ms to converge on a new rectifier voltage target. It should be understood that the instantaneous transient response of the system is open loop and dependent on the Rx coil output impedance at that operating point. More details on this will be covered in the section Receiver Coil LoadLine Analysis. The “main loop” will also determine if any conditions in Table 4 are true in order to discontinue power transfer. See Figure 30 which illustrates the active power transfer loop. Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 19 bq51014 is Not Recommended For New Designs bq51013A bq51014 SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 www.ti.com Rx Active Power Transfer Stage Rx Shutdown conditions per the EPT Table? Yes Tx Powered without Rx Active Send EPT packet with reason value No IOUT < 10% of IMAX? Yes VRECT target = 7V. Send control error packets to converge. No Yes VRECT target = 6.3V. Send control error packets to converge. Yes VRECT target = 5.5V. Send control error packets to converge. Yes TERM STATE (bq51014 only) IOUT < 20% of IMAX? No IOUT < 40% of IMAX? No VRECT target= 5.1V. Send control error packets to converge. Measure Rectified Power and Send Value to Tx BQ51014? No Figure 30. Active Power Transfer Flow Diagram Another requirement of the WPC v1.0 specification is to send the measured rectifier power. This entitles the Rx to determine the rectifier voltage and output current in order to report this to the Tx as a percentage of the maximum output power. This is also handled in the active power transfer loop. If the device is a bq51014, a special state called the “TERM STATE” is enabled in the active power transfer loop. This state is used to determine the level of the output current versus the programmed level of termination current (set by the KTERM factor and RTERM resistor). The primary purpose of this feature is to determine if the charge status is 100% based on the output current from the Rx. In a condition where the mobile device battery is fully charged, a low system current (output current from Rx) signature can be determined. This current level (signature) is set by the end system designer and is termed ITERM-HI. In addition to this current level, there is a noload termination current level termed ITERM-LO which is fixed at 40 mA. For the high termination condition to be 20 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 bq51014 is Not Recommended For New Designs bq51013A bq51014 www.ti.com SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 true, the output current must be between ITERM-HI and ITERM-LO for approximately 180s. Once this condition is true, the Rx will send charge status of 100% to the Tx. The Tx can then illustrate that the mobile device has been fully charged (100% charged). If the output current remains below ITERM-LO for ~7s then the charge status of 100% is immediately sent. This condition can occur if the mobile device is put into a low standby mode after the battery is fully charged. See Figure 31 for the flow diagram of the “TERM STATE”. TERM STATE (bq51014 only) Yes IOUT < 45mA? Yes Send charge status100% and reset t TERM-LO timer Yes Send charge status100% and reset t TERM-HI timer tTERM-LO Expired? No No Yes IOUT < ITERM-HI? tTERM-HI Expired? No No Rx Active Power Transfer Stage Figure 31. TERM STATE Flow Diagram for the bq51014 Only Dynamic Rectifier Control The Dynamic Rectifier Control algorithm offers the end system designer optimal transient response for a given max output current setting. This is achieved by providing enough voltage headroom across the internal regulator at light loads in order to maintain regulation during a load transient. The WPC system has a relatively slow global feedback loop where it can take up to 90 ms to converge on a new rectifier voltage target. Therefore, a transient response is dependent on the loosely coupled transformers output impedance profile. The Dynamic Rectifier Control allows for a 2 V change in rectified voltage before the transient response will be observed at the output of the internal regulator (output of the bq5101x). A 1-A application allows up to a 2 Ω output impedance. The Dynamic Rectifier Control behavior is illustrated in Figure 7 where RILIM is set to 220 Ω. Dynamic Efficiency Scaling The Dynamic Efficiency Scaling feature allows for the loss characteristics of the bq5101x to be scaled based on the maximum expected output power in the end application. This effectively optimizes the efficiency for each application. This feature is achieved by scaling the loss of the internal LDO based on a percentage of the maximum output current. Note that the maximum output current is set by the KIMAX term and the RILIM resistance (where RILIM = KIMAX / IMAX). The flow diagram show in Figure 30 illustrates how the rectifier is dynamically controlled (Dynamic Rectifier Control) based on a fixed percentage of the IMAX setting. The below table summarizes how the rectifier behavior is dynamically adjusted based on two different RILIM settings. Table 1. Output Current Percentage RILIM = 500Ω IMAX = 0.5A RILIM = 220 Ω IMAX = 1.14 A VRECT 0 to 10% 0 A to 0.05 A 0 A to 0.114 A 7.08 V 10 to 20% 0.05 A to 0.1A 0.114 A to 0.227 A 6.28 V 20 to 40% 0.1 A to 0.2 A 0.227 A to 0.454 A 5.53 V >40% > 0.2 A > 0.454 A 5.11 V Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 21 bq51014 is Not Recommended For New Designs bq51013A bq51014 SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 www.ti.com Figure 8 illustrates the shift in the Dynamic Rectifier Controll behavior based on the two different RILIM settings. With the rectifier voltage (VRECT) being the input to the internal LDO, this adjustment in the Dynamic Rectifier Control thresholds will dynamically adjust the power dissipation across the LDO where: ( ) PDIS = VRECT - VOUT × IOUT (1) Figure 6 illustrates how the system efficiency is improved due to the Dynamic Efficiency Scaling feature. Note that this feature balances efficiency with optimal system transient response. RILIM Calculations The bq5101x includes a means of providing hardware overcurrent protection by means of an analog current regulation loop. The hardware current limit provides an extra level of safety by clamping the maximum allowable output current (e.g. a current compliance). The RILIM resistor size also set the thresholds for the dynamic rectifier levels and thus providing efficiency tuning per each application’s maximum system current. The calculation for the total RILIM resistance is as follows: R ILIM = 250 IMAX IILIM = 1.2 ´ IMAX = 300 R ILIM R ILIM = R1 + 140 (2) Where IMAX is the expected maximum output current during normal operation and IILIM is the hardware over current limit. When referring to the application diagram shown in Figure 2, RILIM is the sum of 140 and the R1 resistance (e.g. the total resistance from the ILIM pin to GND). Termination Calculations (bq51014 only) The bq51014 includes a programmable upper termination threshold. This pin can be used to send the charge status 100% packet (CS100) to the transmitter in order to indicate a full charge status. The header for this packet is 0x05. Note that this packet does not turn off the transmitter and is only used as an informative indication of the mobile device’s charge status. The upper termination threshold is calculated using Equation 3: R TERM = 200 ´ %IMAX I %IMAX = TERM-HI ´100 IMAX IMAX = 250 R ILIM (3) The 200 constant is specified in the datasheet as KTERM. The upper termination threshold is set as a percentage of the IIMAX setting. For example, if the ILIM resistance is set to 250 Ω the IIMAX current will be 1A (250 ÷ 250). If the upper termination threshold is desired to be 100 mA, this would be 10% of IIMAX. The RTERM resistor would then equal 2kΩ (200 x 10). When the output current is in between ITERM-HI and ITERM-LO, the CS100 packet is sent approximately every 3 min. When the output current is below ITERM-LO, the CS100 packet is sent approximately every 7 seconds. The output current must remain in one of the termination conditions for that specific amount of time for the first CS100 packet to be sent (deglitch). See Figure 32 for details: I OUT ITERM-HI ITERM-LO t t LO = 7s tHI = 180s Figure 32. Termination Deglitch Timings for the CS100 Packet 22 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 bq51014 is Not Recommended For New Designs bq51013A bq51014 www.ti.com SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 Input Overvoltage If the input voltage suddenly increases in potential (e.g. a change in position of the equipment on the charging pad), the voltage-control loop inside the bq5101x becomes active, and prevents the output from going beyond VOUT-REG. The receiver then starts sending back error packets to the transmitter every 30ms until the input voltage comes back to the VRECT-REG target, and then maintains the error communication every 250ms. If the input voltage increases in potential beyond VOVP, the IC switches off the LDO and communicates to the primary to bring the voltage back to VRECT-REG. In addition, a proprietary voltage protection circuit is activated by means of CCLAMP1 and CCLAMP2 that protects the IC from voltages beyond the maximum rating of the IC (e.g. 20V). Adapter Enable Functionality and EN1/EN2 Control Figure 3 is an example application that shows the bq5101x used as a wireless power receiver that can power mutliplex between wired or wireless power for the down-system electronics. In the default operating mode pins EN1 and EN2 are low, which activates the adapter enable functionality. In this mode, if an adapter is not present the AD pin will be low, and AD-EN pin will be pulled to the higher of the OUT and AD pins so that the PMOS between OUT and AD will be turned off. If an adapter is plugged in and the voltage at the AD pin goes above 3.6V then wireless charging is disabled and the AD-EN pin will be pulled approximately 4V below the AD pin to connect AD to the secondary charger. The difference between AD and AD-EN is regulated to a maximum of 7V to ensure the VGS of the external PMOS is protected. The EN1 and EN2 pins include internal 200kΩ pull-down resistors, so that if these pins are not connected bq5101x defaults to AD-EN control mode. However, these pins can be pulled high to enable other operating modes as described in Table 2: Table 2. EN1 EN2 Result 0 0 Adapter control enabled. If adapter is present then secondary charger is powered by adapter, otherwise wireless charging is enabled when wireless power is available. Communication current limit is enabled. 0 1 Disables communication current limit. 1 0 AD-EN is pulled low, whether or not adapter voltage is present. This feature can be used, e.g., for USB OTG applications. 1 1 Adapter and wireless charging are disabled, i.e., power will never be delivered by the OUT pin in this mode. Table 3. (1) (2) Adaptive Communication Limit EPT Termination Disabled Enabled Not Sent to Tx Disabled Disabled Not Sent to Tx N/A Sent to Tx N/A Sent to Tx EN1 EN2 Wireless Power Wired Power OTG Mode 0 0 Enabled Priority (1) 0 1 Enabled Priority (1) 1 0 Disabled Enabled 1 1 Disabled Disabled Enabled (2) Disabled If both wired and wireless power are present, wired power is given priority. Allows for a boost-back supply to be driven from the output terminal of the Rx to the adapter port via the external back-to-back PMOS FET. As described in Table 2, pulling EN2 high disables the adapter mode and only allows wireless charging. In this mode the adapter voltage will always be blocked from the OUT pin. An application example where this mode is useful is when USB power is present at AD, but the USB is in suspend mode so that no power can be taken from the USB supply. Pulling EN1 high enables the off-chip PMOS regardless of the presence of a voltage. This function can be used in USB OTG mode to allow a charger connected to the OUT pin to power the AD pin. Finally, pulling both EN1 and EN2 high disables both wired and wireless charging. Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 23 bq51014 is Not Recommended For New Designs bq51013A bq51014 SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 www.ti.com NOTE It is required to connect a back-to-back PMOS between AD and OUT so that voltage is blocked in both directions. Also, when AD mode is enabled no load can be pulled from the RECT pin as this could cause an internal device overvoltage in bq5101x. End Power Transfer Packet (WPC Header 0x02) The WPC allows for a special command for the receiver to terminate power transfer from the trasmitter termed End Power Transfer (EPT) packet. Table 4 specifies the v1.0 Reasons columb and their responding data field value. The Condition column corresponds to the values sent by the bq5101x for a given reason. Table 4. Reason Value Condition Unknown 0x00 AD > 3.6V Charge Complete 0x01 TS/CTRL = 1, or EN1 = 1, or = Internal Fault 0x02 TJ > 150°C or RILIM < 100Ω Over Temperature 0x03 TS < VHOT, TS > VCOLD, or TS/CTRL < 100mV Over Voltage 0x04 Not Sent Over Current 0x05 IOUT > 90% of ILIM (bq51014 only) Battery Failure 0x06 Not Sent Reconfigure 0x07 Not Sent No Response 0x08 VRECT target doesn't converge Over Current Shutdown (bq51014) The bq51014 includes an over current shutdown feature where the Rx sends an end power transfer packet to the Tx when the output current reaches 100% of the IILIM setting or 120% of the IIMAX setting. The Tx will shut down as soon as the end power transfer packet is received which discontinues power transfer. This feature disallows the Rx from operating in a current limit situation in order to protect from down system shorts or failures. Status Outputs bq5101x has one status output, CHG. This output is an open-drain NMOS device that is rated to 20V. The opendrain FET connected to the CHG pin will be turned on whenever the output of the power supply is enabled. Please note, the output of the power supply will not be enabled if the VRECT-REG does not converge at the no-load target voltage. WPC Communication Scheme The WPC communication uses a modulation technique termed “back-scatter modulation” where the receiver coil is dynamically loaded in order to provide amplitude modulation of the transmitters coil voltage and current. This scheme is possible due to the fundamental behavior between two loosely coupled inductors (e.g. between the Tx and Rx coil). This type of modulation can be accomplished by switching in and out a resistor at the output of the rectifier, or by switching in and out a capacitor across the AC1/AC2 net. Figure 33 shows how to implement resistive modulation. CRES1 AC1 VRECT R MOD COIL C RES2 AC2 GND Figure 33. Resistive Modulation 24 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 bq51014 is Not Recommended For New Designs bq51013A bq51014 www.ti.com SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 Figure 34 Shows how to implement capacitive modulation. CRES1 AC1 VRECT C MOD COIL C RES2 AC2 GND Figure 34. Capacitive Modulation The amplitude change in Tx coil voltage or current can be detected by the transmitters decoder. The resulting signal observed by the Tx is shown in Figure 35. Power AC to DC bq5101x Drivers Voltage Conditioning Rectification Load Communication Controller V/I Sense Controller bq500210 Transmitter 0 Receiver 1 0 1 0 TX COIL VOLTAGE / CURRENT Figure 35. The WPC protocol uses a differential bi-phase encoding scheme to modulate the data bits onto the Tx coil voltage/current. Each data bit is aligned at a full period of 0.5 ms (tCLK) or 2 kHz. An encoded ONE results in two transitions during the bit period and an encoded ZERO results in a single transition. See Figure 36 for an example of the differential bi-phase encoding. Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 25 bq51014 is Not Recommended For New Designs bq51013A bq51014 SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 www.ti.com Figure 36. Differential Bi-phase Encoding Scheme (WPC volume 1: Low Power, Part 1 Interface Definition) The bits are sent LSB first and use an 11-bit asynchronous serial format for each portion of the packet. This includes one start bit, n-data bytes, a parity bit, and a single stop bit. The start bit is always ZERO and the parity bit is odd. The stop bit is always ONE. Figure 37 shows the details of the asynchronous serial format. Figure 37. Asynchronous Serial Formatting (WPC volume 1: Low Power, Part 1 Interface Definition) Each packet format is organized as shown in Figure 38. Preamble Header Message Checksum Figure 38. Packet Format (WPC volume 1: Low Power, Part 1 Interface Definition) Figure 27 above shows an example waveform of the receiver sending a rectified power packet (header 0x04). Communication Modulator bq5101x provides two identical, integrated communication FETs which are connected to the pins COM1 and COM2. These FETs are used for modulating the secondary load current which allows bq5101x to communicate error control and configuration information to the transmitter. Figure 39 below shows how the COMM pins can be used for resistive load modulation. Each COMM pin can handle at most a 24Ω communication resistor. Therefore, if a COMM resistor between 12Ω and 24Ω is required COM1 and COM2 pins must be connected in parallel. bq5101x does not support a COMM resistor less than 12Ω. 26 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 bq51014 is Not Recommended For New Designs bq51013A bq51014 www.ti.com SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 RECTIFIER 24W COMM1 24W COMM2 COMM_DRIVE Figure 39. Resistive Load Modulation In addition to resistive load modulation, the bq5101x is also capable of capacitive load modulation as shown in Figure 40 below. In this case, a capacitor is connected from COM1 to AC1 and from COM2 to AC2. When the COMM switches are closed there is effectively a 22 nF capacitor connected between AC1 and AC2. Connecting a capacitor in between AC1 and AC2 modulates the impedance seen by the coil, which will be reflected in the primary as a change in current. Figure 40. Capacitive Load Modulation Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 27 bq51014 is Not Recommended For New Designs bq51013A bq51014 SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 www.ti.com Adaptive Communication Limit The Qi communication channel is established via backscatter modulation as described in the previous sections. This type of modulation takes advantage of the loosely coupled inductor relationship between the Rx and Tx coil. Essentially the switching in-and-out of the communication capacitor or resistor adds a transient load to the Rx coil in order to modulate the Tx coil voltage/current waveform (amplitude modulation). The consequence of this technique is that a load transient (load current noise) from the mobile device has the same signature. In order to provide noise immunity to the communication channel, the output load transients must be isolated from the Rx coil. The proprietary feature Adaptive Communication Limit achieves this by dynamically adjusting the current limit of the regulator. When the regulator is put in current limit, any load transients will be offloaded to the battery in the system. Note that this requires the battery charger IC to have input voltage regulation (weak adapter mode). The output of the Rx appears as a weak supply if a transient occurs above the current limit of the regulator. The Adaptive Communication Limit feature has two current limit modes and is detailed in the table below: Table 5. IOUT Communication Current Limit < 300 mA Fixed 400 mA > 300 mA IOUT + 50 mA The first mode is illustrated in Figure 25. In this plot, an output load pulse of 300 mA is periodically introduced on a DC current level of 200 mA. Therefore, the 400 mA current limit is enabled. The pulses on VRECT indicate that a communication packet event is occurring. When the output load pulse occurs, the regulator limits the pulse to a constant 400 mA and; therefore, preserves communication. Note that VOUT drops to 4.5 V instead of GND. A charger IC with an input voltage regulation set to 4.5 V allows this to occur by offloading the load transient support to the mobile device’s battery The second mode is illustrated in Figure 26. In this plot, an output pulse of 200 mA is periodically introduced on a DC current level of 400 mA. Therefore, the tracking current mode (IOUT + 50 mA) is enabled. In this mode the bq5101x measures the active output current and sets the regulators current limit 50 mA above this measurement. When the load pulse occurs during a communication packet event, the output current is regulated to 450 mA. As the communication packet event has finished the output load is allowed to increase. Note that during the time the regulator is in current limit VOUT is reduced to 4.5 V and 5 V when not in current limit. Synchronous Rectification The bq5101x provides an integrated, self-driven synchronous rectifier that enables high-efficiency AC to DC power conversion. The rectifier consists of an all NMOS H-Bridge driver where the backgates of the diodes are configured to be the rectifier when the synchronous rectifier is disabled. During the initial startup of the WPC system the synchronous rectifier is not enabled. At this operating point, the DC rectifier voltage is provided by the diode rectifier. Once VRECT is greater than UVLO, half synchronous mode will be enabled until the load current surpasses 120 mA. Above 120 mA the full synchronous rectifier stays enabled until the load current drops back below 100 mA where half synchronous mode is enabled instead. Temperature Sense Resistor Network (TS) bq5101x includes a ratiometric external temperature sense function. The temperature sense function has two ratiometric thresholds which represent a hot and cold condition. An external temperature sensor is recommended in order to provide safe operating conditions for the receiver product. This pin is best used for monitoring the surface that can be exposed to the end user (e.g. place the NTC resistor closest to the user). Figure 41 allows for any NTC resistor to be used with the given VHOT and VCOLD thresholds. 28 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 bq51014 is Not Recommended For New Designs bq51013A bq51014 www.ti.com SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 VTSB (2.2V) 20kΩ R2 TS-CTRL R1 R3 NTC Figure 41. NTC Circuit Used for Safe Operation of the Wireless Receiver Power Supply The resistors R1 and R3 can be solved by resolving the system of equations at the desired temperature thresholds. The two equations are: ) ) ( ( æ R R + R1 ö÷ ç 3 NTC TCOLD ç ÷ + R1 ÷ ç R 3 + R NTC TCOLD ø ´100 %VCOLD = è æ R R + R1 ö÷ ç 3 NTC TCOLD ç ÷ + R2 + R1 ÷ ç R 3 + R NTC TCOLD è ø ) ) æ R R + R1 ) ö÷ ç 3 ( NTC THOT ç ÷ + R1 )÷ ç R 3 + (R NTC THOT ø ´100 %VHOT = è æ R R + R1 ) ö÷ ç 3 ( NTC THOT ç ÷ + R2 R R R + + ç 3 ( NTC 1 )÷ø THOT è ( ( (4) Where: R NTC TCOLD R NTC THOT bæçç 1TCOLD-1To ö÷÷ ø = R oe è bæçç 1 -1To ö÷÷ ø = R oe è THOT (5) where, TCOLD and THOT are the desired temperature thresholds in degrees Kelvin. RO is the nominal resistance and β is the temperature coefficient of the NTC resistor. RO is fixed at 20 kΩ. An example solution is provided: • R1 = 4.23kΩ • R3 = 66.8kΩ where the chosen parameters are: • %VHOT = 19.6% • %VCOLD = 58.7% Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 29 bq51014 is Not Recommended For New Designs bq51013A bq51014 SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 • • • • www.ti.com TCOLD = –10°C THOT = 100°C β = 3380 RO = 10kΩ The plot of the percent VTSB vs. temperature is shown in Figure 42: Figure 42. Example Solution for an NTC resistor with RO = 10KΩ and β = 4500 Figure 43 illustrates the periodic biasing scheme used for measuring the TS state. The TS_READ signal enables the TS bias voltage for 24ms. During this period the TS comparators are read (each comparator has a 10 ms deglitch) and appropriate action is taken based on the temperature measurement. After this 24ms period has elapsed, the TS_READ signal goes low, which causes the TS-Bias pin to become high impedance. During the next 35ms (priority packet period) or 235ms (standard packet period), the TS voltage is monitored and compared to 100mV. If the TS voltage is greater than 100mV then a secondary device is driving the TS/CTRL pin and a CTRL = ‘1’ is detected. 240 ms ms 240 Figure 43. Timing Diagram for TS Detection Circuit 30 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 bq51014 is Not Recommended For New Designs bq51013A bq51014 www.ti.com SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 3-state Driver Recommendations for the TS-CTRL Pin The TS-CTRL pin offers three functions with one 3-state driver interface 1. NTC temperature monitoring, 2. Fault indication, 3. Charge done indication A 3-state driver can be implemented with the circuit in Figure 44 and the use of two GPIO connections. BATT M3 TERM TS-CTRL FAULT M4 Figure 44. 3-state Driver for TS-CTRL Note that the signals “TERM” and “FAULT” are given by two GPIO’s. The truth table for this circuit is found in Table 6: Table 6. TERM FAULT F (Result) 1 0 Z (Normal Mode) 0 0 Charge Complete 1 1 System Fault The default setting is TERM = 1 and FAULT = 0. In this condition, the TS-CTRL net is high impedance (hi-z) and; therefore, the NTC is function is allowed to operate. When the TS-CTRL pin is pulled to GND by setting FAULT = 1, the Rx is shutdown with the indication of a fault. When the TS-CTRL pin is pulled to the battery by setting TERM = 1, the Rx is shutdown with the indication of a charge complete condition. Therefore, the host controller can indicate whether the Rx is system is turning off due to a fault or due to a charge complete condition. Thermal Protection The bq5101x includes a thermal shutdown protection. If the die temperature reaches TJ(OFF), the LDO is shut off to prevent any further power dissipation. Series and Parallel Resonant Capacitor Selection Shown in Figure 2, the capacitors C1 (series) and C2 (parallel) make up the dual resonant circuit with the receiver coil. These two capacitors must be sized correctly per the WPC v1.0 specification. Figure 45 illustrates the equivalent circuit of the dual resonant circuit: C1 Ls’ C2 Figure 45. Dual Resonant Circuit with the Receiver Coil Section 4.2 (Power Receiver Design Requirements) in volume 1 of the WPC v1.0 specification highlights in detail the sizing requirements. To summarize, the receiver designer will be required take inductance measurements with a fixed test fixture. The test fixture is shown in Figure 46: Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 31 bq51014 is Not Recommended For New Designs bq51013A bq51014 SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 www.ti.com Figure 46. WPC v1.0 Receiver Coil Test Fixture for the Inductance Measurement Ls’ (copied from System Description Wireless Power Transfer, volume 1: Low Power, Part 1 Interface Definition, Version 1.0.1, Figure 4-4) The primary shield is to be 50 mm x 50 mm x 1 mm of Ferrite material PC44 from TDK Corp. The gap dZ is to be 3.4 mm. The receiver coil, as it will be placed in the final system (e.g. the back cover and battery must be included if the system calls for this), is to be placed on top of this surface and the inductance is to be measured at 1-V RMS and a frequency of 100 kHz. This measurement is termed Ls’. The same measurement is to be repeated without the test fixture shown in Figure 11. This measurement is termed Ls or the free-space inductance. Each capacitor can then be calculated using Equation 6: é C =ê 1 ê ë ù 2 f × 2p × L' ú S Sú ( é C =ê 2 ê ë ) -1 û 2 (fD × 2p) ù 1 ×L - ú S C ú 1û -1 (6) Where fS is 100 kHz +5/-10% and fD is 1 MHz ±10%. C1 must be chosen first prior to calculating C2. The quality factor must be greater than 77 and can be determined by Equation 7: Q= 2p× f × LS D R (7) where R is the DC resistance of the receiver coil. All other constants are defined above. Receiver Coil Load-Line Analysis When choosing a receiver coil, it is recommend to analyze the transformer characteristics between the primary coil and receiver coil via load-line analysis. This will capture two important conditions in the WPC system: 1. Operating point characteristics in the closed loop of the WPC system. 2. Instantaneous transient response prior to the convergence of the new operating point. An example test configuration for conducting this analysis is shown in Figure 47: 32 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 bq51014 is Not Recommended For New Designs bq51013A bq51014 SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 A www.ti.com CP VIN CS LP L S CD CB RL V Figure 47. Load-Line Analysis Test Bench Where: • VIN is a square-wave power source that should have a peak-to-peak operation of 19V. • CP is the primary series resonant capacitor (i.e. 100 nF for Type A1 coil). • LP is the primary coil of interest (i.e. Type A1). • LS is the secondary coil of interest. • CS is the series resonant capacitor chosen for the receiver coil under test. • CD is the parallel resonant capacitor chosen for the receiver coil under test. • CB is the bulk capacitor of the diode bridge (voltage rating should be at least 25 V and capacitance value of at least 10µ F) • V is a Kelvin connected voltage meter • A is a series ammeter • RL is the load of interest It is recommended that the diode bridge be constructed of Schottky diodes. The test procedure is as follows • Supply a 19V AC signal to LP starting at a frequency of 210 kHz • Measure the resulting rectified voltage from no load to the expected full load • Repeat the above steps for lower frequencies (stopping at 110 kHz) An example load-line analysis is shown in Figure 48: 20 18 175 kHz 160 kHz 16 150 kHz VRECT (V) 14 140 kHz 125 kHz 12 115 kHz 135 kHz 10 130 kHz 8 6 4 2 0 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 LOAD (A) Figure 48. Example Load-Line Results Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 33 bq51014 is Not Recommended For New Designs bq51013A bq51014 SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 www.ti.com What this plot conveys about the operating point is that a specific load and rectifier target condition consequently results in a specific operating frequency (for the type A1 TX). For example, at 1 A the dynamic rectifier target is 5.15 V. Therefore, the operating frequency will be between 150kHz and 160kHz in the above example. This is an acceptable operating point. If the operating point ever falls outside the WPC frequency range (110kHz – 205kHz), the system will never converge and will become unstable. In regards to transient analysis, there are two major points of interest: 1. Rectifier voltage at the ping frequency (175kHz). 2. Rectifier voltage droop from no load to full load at the constant operating point. In this example, the ping voltage will be approximately 5 V. This is above the UVLO of the bq5101x and; therefore, startup in the WPC system can be ensured. If the voltage is near or below the UVLO at this frequency, then startup in the WPC system may not occur. If the max load step is 1 A, the droop in this example will be Approximately1V with a voltage at 1 A of Approximately 5.5 V (140 kHz load-line). To analyze the droop locate the load-line that starts at 7 V at no-load. Follow this load-line to the max load expected and take the difference between the 7V no-load voltage and the full-load voltage at that constant frequency. Ensure that the full-load voltage at this constant frequency is above 5V. If it descends below 5V, the output of the power supply will also droop to this level. This type of transient response analysis is necessary due to the slow feedback response of the WPC system. This simulates the step response prior to the WPC system adjusting the operating point. NOTE Coupling between the primary and secondary coils will worsen with misalignment of the secondary coil. Therefore, it is recommended to re-analyze the load-lines at multiple misalignments to determine where, in planar space, the receiver will discontinue operation. 34 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 bq51014 is Not Recommended For New Designs bq51013A bq51014 www.ti.com SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 Recommended Rx coils can be found in Table 7: Table 7. Manufacturer Part Number Dimensions Ls Ls’ Output Current Range Application TDK WR-483250-15M2-G 48 x 32mm 10.4 μH 12 μH (1) 50-1000 mA General 5V Power Supply TDK WR-383250-17M2-G 38 x 32mm 11.1 μH 12.3 μH (1) 50-1000 mA Space limited 5V Power Supply Vishay IWAS-4832FF-50 48 x 32mm 10.8 μH 12.5 μH (1) 50-1000 mA General 5V Power Supply Mingstar 312-00012 48 x 32mm 10.8 μH 12.9 μH (1) 50-1000 mA General 5V power Supply Mingstar 312-00015 28 x 14mm 36.5 μH 45 μH (2) 150-1000 mA Space limited 5V Power Supply (1) (2) Ls’ measurements conducted with a standard battery behind the Rx coil assembly. This measurement is subject to change based on different battery sizes, placements, and casing material. Battery not present behind the Rx coil assembly. Subject to drop in inductance depending on the placement of the battery. It is recommended that all inductance measurements are repeated in the designers specific system as there are many influence on the final measurements. Package Summary YFP Package (Top View) A1 A2 A3 A4 B1 B2 B3 B4 C1 C2 C3 C4 D1 D2 D3 D4 E1 E2 E3 E4 F1 F2 F3 F4 G1 G2 G3 G4 YFP Package Symbol (Top Side Symbol for bq51013A) D TI YMLLLLS bq51013A 0-Pin A1 Marker, TI-TI Letters, YM- Year Month Date Code, LLLL-Lot Trace Code, S-Assembly Site Code E Figure 49. Chip Scale Packaging Dimensions • • D = 3.0mm ± 0.035mm E = 1.88mm ± 0.035mm Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 35 bq51014 is Not Recommended For New Designs bq51013A bq51014 SLUSAY6B – MARCH 2012 – REVISED OCTOBER 2013 www.ti.com REVISION HISTORY Changes from Original (March 2012) to Revision A • Page Deleted VRECT-TRACK from the Electrical Characteristics table ............................................................................................... 6 Changes from Revision A (June 2012) to Revision B Page • Changed AC1, AC2 input voltage spec MINIMUM value from –0.3 to –0.8 in the Absolute Maximum Ratings table ......... 2 • Changed condition statement of Electrical Characteristics section from "0°C to 125°C" to "–40°C to 125°C" .................... 6 • Changed UVLO spec MIN value from "2.6" to "2.5" ............................................................................................................. 6 • Changed VOUT-REG spec MIN value from "4.85" to "4.82 for ILOAD = 1000 mA condition. ...................................................... 6 • Changed VOUT-REG spec MIN value from "4.95" to "4.92 for ILOAD = 10 mA condition. .......................................................... 6 36 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated Product Folder Links: bq51013A bq51014 PACKAGE OPTION ADDENDUM www.ti.com 19-Oct-2022 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan (2) Lead finish/ Ball material MSL Peak Temp Op Temp (°C) Device Marking (3) Samples (4/5) (6) BQ51013ARHLR ACTIVE VQFN RHL 20 3000 RoHS & Green NIPDAU Level-2-260C-1 YEAR 0 to 125 BQ51013A Samples BQ51013ARHLT ACTIVE VQFN RHL 20 250 RoHS & Green NIPDAU Level-2-260C-1 YEAR 0 to 125 BQ51013A Samples BQ51013AYFPR ACTIVE DSBGA YFP 28 3000 RoHS & Green SNAGCU Level-1-260C-UNLIM 0 to 125 BQ51013A Samples BQ51013AYFPT ACTIVE DSBGA YFP 28 250 RoHS & Green SNAGCU Level-1-260C-UNLIM 0 to 125 BQ51013A Samples BQ51014YFPR NRND DSBGA YFP 28 3000 RoHS & Green SNAGCU Level-1-260C-UNLIM 0 to 125 BQ51014 BQ51014YFPT NRND DSBGA YFP 28 250 RoHS & Green SNAGCU Level-1-260C-UNLIM 0 to 125 BQ51014 (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may reference these types of products as "Pb-Free". RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption. Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of