SY6974BQCC

Application Note: SY6974B 3A, Single Cell Li-Ion DC/DC Switching Charger with I2C Control, USB Detection and OTG JEITA Compliant, Power Path Management General Description The SY6974B is a fully-integrated switching battery charger with system power path management devices for single cell Li-ion and Li-polymer battery in a wide range of tablet and other portable devices. Its low impedance power path optimizes switching conversion efficiency, reduces battery charging time and extends battery life during the discharging mode. The I2C serial interface with charging and system settings makes the device a truly flexible solution. The device supports a wide range of input sources, including standard USB host port, USB charging port and non-standard DC adapter. The SY6974B takes the result from the internal USB port identification circuit thru DP/DM compliant with BC1.2. Meanwhile, the SY6974B meets USB Onthe-Go operation power rating specification by supplying 5.15V (programmable) on BUS with current limit up to 1.2A (programmable). The power path management regulates the system voltage slightly above battery voltage but does not drop below 3.5V minimum system voltage (programmable). With this feature, the switching converter will keep working to support the system load even when the battery is completely depleted or removed. When the input current limit or voltage limit is reached, the power path management will reduce the charging current to zero firstly. If the system load continues to increase, the power path will discharge the battery to provide the power required by system. This supplement mode operation prevents overloading the input source. AN_SY6974B Rev.0.9 © 2020 Silergy Corp. The device initiates and completes a charging cycle without software control. It automatically detects the battery voltage and charges the battery in five phases: battery short, preconditioning, constant current and constant voltage and top-off charging (optional). At the end of the charging cycle, the charger automatically will terminate when the charge current is below a preset limit in the constant voltage phase. When the full battery falls below the recharge threshold, the charger will automatically start another charging cycle. The SY6974B can be compliant with JEITA spec for the 4.2V Li-ion battery. The device provides various safety features for battery charging and system operation, including negative thermistor monitoring, charging safety timer and over-voltage / over-current protections. The thermal regulation will reduce charge current when the junction temperature exceeds 110°C (programmable). The STAT output reports the charging status and any fault conditions. The INT immediately will notify the host when a fault occurs. The SY6974B are available in QFN4x4-24 package. Ordering Information SY6974 □(□□)□ Temperature Code Package Code Optional Spec Code Ordering Number SY6974BQCC Package type Note QFN4x4-24 Silergy Corp. Confidential- Prepared for Customer Use Only -1All Rights Reserved. AN_SY6974B Features • • • • High Efficiency 3A 1.5MHz Buck Mode Charger – Support 3.9V-13.5V Input Voltage Range – Programmable IDPM/VDPM to Support the USB and Adapter – 3.856V-4.624V Adjustable Charge Voltage – Support Narrow VDC Power Path Management – JEITA Compliance – ±0.5% Charge Voltage Regulation – Charge Status Outputs for LED or Host Processor Maximum 1.2A 1.5MHz Boost OTG Current – 4.85V-5.3V Adjustable OTG Output Voltage – Selectable OTG Output Current Limit – ±1.5% Output Regulation in Boost Mode – Soft-Start up to 500µF Capacitive Load – Constant Current (CC) Limit • • Full BATFET Control to Support Shipping Mode, Wake up, and System Reset Safety – Battery Temperature Sensing for Charge and Boost Mode – Battery Charging Safety Timer – Thermal Regulation and Thermal Shutdown – Input/System over-Voltage Protection – MOSFET over-Current Protection Low Battery Leakage Current and Support Shipping Mode 4mm x 4mm QFN-24 Package Applications • • • • Smart Phone Tablet PC Power Bank Portable Internet Devices Typical Application 3.9V-13.5V USB VBUS SY6974B 1µF PMID 10µF VAC PGND DM DP 1µH SYSTEM LX 47nF 10µF 10µF BST SYS STAT SYS VBIAS BAT 10µF Battery SCL Host SDA /INT REGN 4.7µF /CE 5.23k /QON NTC Power Pad 10k (103-AT) 30.1k Figure 1. Schematic Diagram AN_SY6974B Rev.0.9 © 2020 Silergy Corp. Silergy Corp. Confidential- Prepared for Customer Use Only -2All Rights Reserved. AN_SY6974B BUS PMID REGN BST LX LX Pinout 24 23 22 21 20 19 17 PGND DM 3 16 SYS STAT 4 15 SYS SCL 5 14 BAT SDA 6 13 BAT 7 8 9 10 11 12 /QON 2 NTC DP NC PGND /CE 18 NC 1 /INT VAC (QFN4x4-24) Top Mark: DDNxyz(device code: DDN, x=year code, y=week code, z= lot number code) Pin Name Pin No Pin Description VAC DP 1 2 DM 3 STAT 4 SCL SDA 5 6 /INT 7 NC 8, 10 /CE 9 NTC 11 /QON 12 BAT 13,14 Charge input voltage sense. This pin must be connected close to BUS pin. USB identification port. USB detection strategy is compliant with BC1.2. SDP, CDP, DCP and adapter port can be identified according to the detection results thru DP/DM pins. Open drain charge status output to indicate various charger operation. Connect to the pull up rail via 10kΩ resistor. Low indicates charge in progress. High indicates charge complete or charge disabled. When any charge fault condition occurs, STAT pin will blink at 1Hz. The STAT pin function can be disabled when STAT_DIS bit is set. I2C Interface clock. Connect SCL to the logic rail through a 10kΩ resistor. I2C Interface data. Connect SDA to the logic rail through a 10kΩ resistor. Open-drain interrupt output. Connect the /INT to a logic rail via 10kΩ resistor. The /INT pin sends active low, 256μs pulse to host to report charger device status and fault. No connect. Active low charge enable pin. Battery charging will be enabled when REG01[4]=1 and /CE pin =Low. /CE pin must be pulled high or low. Connect a resistor divider from REGN to NTC to GND to achieve battery thermal protection. Charge will suspend when NTC pin is out of range. Recommend 103AT-2 thermistor. BATFET enable control in shipping mode and BATFET reset function. When BATFET is in shipping mode, logic high to low transition on this pin with minimum of TQON_LOW low level will turn on BATFET to exit shipping mode. This pin is internally pulled up to default high logic. When BUS is not plugged in and BATFET_DIS=0, a logic low of TQON_RST will reset SYS (system power) by turning BATFET off for TBATFET_RST and then re-enable BATFET. Battery connection point to the positive terminal of the battery pack. The internal BATFET is connected between BAT and SYS. Connect a 10μF closely to the BAT pin AN_SY6974B Rev.0.9 © 2020 Silergy Corp. Silergy Corp. Confidential- Prepared for Customer Use Only -3All Rights Reserved. AN_SY6974B SYS 15,16 PGND 17,18 LX BST 19,20 21 REGN 22 PMID 23 BUS 24 Exposed pad - AN_SY6974B Rev.0.9 © 2020 Silergy Corp. System connection point. The internal BATFET is connected between BAT and SYS. When the battery falls below the minimum system voltages, switch mode converter will keep SYS above the minimum system voltage. Power ground connection node. Internally, PGND is connected to the source of the nchannel LSFET. On PCB layout, connect directly to ground connection of input and output capacitors of the charger. Switching node pin. Connect to external inductor. HSFET driver positive supply. Connect a 47nF bootstrap capacitor from LX to BST. LSFET driver positive supply. Connect a 4.7μF ceramic capacitor from REGN to analog GND. The capacitor should be placed close to the IC. REGN also serves as bias rail of NTC pin. Connected to the drain of the reverse blocking MOSFET and the drain of HSFET. Put at least 10μF on PMID to PGND, and place it as close as possible to IC. Charger power input pin. Place a 1μF ceramic capacitor from BUS to PGND and place it as close as possible to IC. Exposed pad beneath the IC for heat dissipation. Always solder exposed pad to the board, and have vias on the Power Pad plane star-connecting to PGND and ground plane for high current power converter. Silergy Corp. Confidential- Prepared for Customer Use Only -4All Rights Reserved. AN_SY6974B Absolute Maximum Ratings (Note 1) BUS, VAC, PMID, LX -------------------------------------------------------------------------------------- -0.3V to +18V BAT, SYS, REGN, DP, DM, STAT, SCL, SDA, /INT, /CE, NTC, /QON, BST-LX ---------------- -0.3V to +6V Package Thermal Resistance (Notes 2) θ JA ------------------------------------------------------------------------------------------------------------------ 27.5°C/W θ JC (top) -------------------------------------------------------------------------------------------------------------- 18°C/W θ JB ---------------------------------------------------------------------------------------------------------------------- 8°C/W  JT------------------------------------------------------------------------------------------------------------------ 0.35°C/W Junction Temperature Range ----------------------------------------------------------------------------- -40°C to +150°C Operating Temperature Range --------------------------------------------------------------------------- -40°C to +150°C Storage Temperature -------------------------------------------------------------------------------------- -65°C to +150°C Lead Temperature (Soldering, 10s) -------------------------------------------------------------------------------- +300°C ESD Susceptibility HBM (Human Body Mode) --------------------------------------------------------------------------------------------- 2kV CDM (Charged Device Mode) ---------------------------------------------------------------------------------------- 200V Recommended Operating Conditions (Note 3) BUS, VAC, PMID, LX ----------------------------------------------------------------------------------------- 0V to +16V BAT, SYS, REGN, DP, DM, STAT, SCL, SDA, /INT, /CE, NTC, /QON, BST-LX ----------------- 0V to +5.5V Junction Temperature Range ------------------------------------------------------------------------------ -40°C to 125°C Ambient Temperature Range ------------------------------------------------------------------------------- -40°C to 85°C AN_SY6974B Rev.0.9 © 2020 Silergy Corp. Silergy Corp. Confidential- Prepared for Customer Use Only -5All Rights Reserved. AN_SY6974B Block Diagram BUS VUVLO VAC Drive - VSLEEP + LDO VDPM - VOVP PMID Q1 + REGN + BST IDPM - EN_HIZ TJ TREG Loop Selection VSYS Q2 PWM Generator LX LX VSYSMIN Protection VCV Q3 VBAT ICC PGND PGND ICHG DP NTC Comparators USB Detection NTC DM SYS SYS Q4 Control Q4 BAT BAT DAC Charge & Discharge Control /QON I2C Interface /INT STAT SCL SDA /CE Figure 2. Block Diagram AN_SY6974B Rev.0.9 © 2020 Silergy Corp. Silergy Corp. Confidential- Prepared for Customer Use Only -6All Rights Reserved. AN_SY6974B Electrical Characteristics (VBUS_UVLOZVBAT, converter not switching VBUS> VBUS_UVLOZ, VBUS>VBAT, converter switching, VBAT=3.8V, ISYS=0A VBAT=4.2V, Boost mode, IBUS=0A, converter switching 3 mA 3.5 mA BUS/BAT Power up BUS Operating Range VBUS_OP 3.9 I2C VSLEEP VSLEEPZ VACOV VACOV_RC VBUS falling, REG06[7:6]=00 5.5 5.7 5.9 V VACOV VBUS rising, REG06[7:6]=11 13.8 14.1 14.4 V VACOV_RC VBUS falling, REG06[7:6]=11 13.5 13.8 14.1 V Battery for Active I2C, no BUS VBAT_UVLOZ Battery Depletion Threshold Battery Depletion Recovery Threshold Bad Adapter Detection Threshold Bad Adapter Detection Hysteresis Bad Adapter Detection Current Source Bad Source Detection Duration VBAT_DPL VBAT rising value to active I2C VBAT falling VBAT falling 2.15 2.1 1.8 2.3 2.3 2.0 2.5 V V V VBAT_DPLZ VBAT rising 2.3 2.55 2.7 V VBUSMIN VBUSMIN_HYST VBUS falling VBUS rising 3.6 3.7 100 3.8 V mV VBUS_UVLOZ 25 170 5.7 V V V mV mV V Sleep Mode Falling Threshold Sleep Mode Rising Threshold BUS over-Voltage Rising Threshold BUS over-Voltage Recovery Threshold BUS over-Voltage Rising Threshold BUS over-Voltage Recovery Threshold no 3.3 2.9 65 250 5.9 13.5 3.5 3.25 120 300 6.1 Rising value to active Falling value VBUS falling, VBUS-VBAT VBUS rising, VBUS-VBAT VBUS rising, REG06[7:6]=00 BUS for Active IC and Battery I2C, IBADSRC 30 mA tBADSRC 30 ms Power Path Management System Regulation Voltage VSYS_MAX System Regulation Voltage VSYS_MIN AN_SY6974B Rev.0.9 © 2020 Silergy Corp. ISYS = 0A, VBAT>VSYSMIN, BATFET off, VBAT up to 4.35V, VSYS=VBAT+50mV ISYS=0A, VBAT780mA ITERM =60mA, ICHG_REG ≤780mA ITERM = 180mA, ICHG_REG > 780mA VBAT falling VBAT rising VBAT