NB621EV-LF-P

NB621 8A, 25V, 600kHz Synchronous Step-Down Converter with Integrated LDO The Future of Analog IC Technology DESCRIPTION FEATURES The NB621 is a high frequency synchronous rectified step-down switch mode converter with a built in internal high side power MOSFET and integrated LDO. It offers a very compact solution to achieve 8A continuous output current over a wide input, load and line range. • • • • • • • • • • • • Current mode operation provides fast transient response and eases loop stabilization. Full protection features include OCP and thermal shut down. The NB621 requires a minimum number of readily available standard external components and is available in a space saving 4mm x 5mm 28-pin QFN package. Wide 5.5V to 25V Operating Input Range 8A Output Current Internal Low RDSON Power MOSFETs Fixed 600kHz switching frequency Sync from 300kHz to 2MHz External Clock Integrated 100mA LDO Internal Compensation Power Good Output Integrated Bootstrap Diode OCP Protection and Thermal Shutdown Output Adjustable from 0.8V to 15V Available in 4mm x 5mm 28-pin QFN package. APPLICATIONS • • • • • • Notebook Systems and I/O Power Networking Systems Digital Set Top Boxes Personal Video Recorders Flat Panel Television and Monitors Distributed Power Systems All MPS parts are lead-free and adhere to the RoHS directive. For MPS green status, please visit MPS website under Products, Quality Assurance page. “MPS” and “The Future of Analog IC Technology” are registered trademarks of Monolithic Power Systems, Inc. TYPICAL APPLICATION (FOR NOTEBOOK) VIN 5.5-25V BST VIN 10uF 100nF 100K VOUT 2.0uH SELH SW VCC 1k 100K 1uF 61.9k NB621 AAM 22K SDRV 20K 2x47uF 82pF 20k PGOOD FB ON/OFF EN/SYNC ON/OFF ENLDO REGO LDO SS GND 4.7uF 22nF NB621 Rev. 1.0 1/21/2014 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2014 MPS. All Rights Reserved. 1 NB621 – 8A, 25V, 600kHz SYNCHRONOUS STEP-DOWN CONVERTER WITH INTEGRATED LDO ORDERING INFORMATION Part Number* Package Top Marking NB621EV QFN28 (4mmx5mm) N621EV * For Tape & Reel, add suffix –Z (e.g. NB621EV–Z); For RoHS compliant packaging, add suffix –LF (e.g. NB621EV–LF–Z). PACKAGE REFERENCE TOP VIEW N/C 28 22 SELH 21 IN 19 20 IN 18 IN N/C 6 17 IN GND 7 16 SW 2 N/C ENLDO 24 23 EN/SYNC SDRV 8 15 BST 1 N/C REGO LDO 27 26 25 PGOOD SW 3 SW 4 SW 5 Exposed pad on back side connected to GND 10 9 11 12 N/C AGND VCC AAM 13 SS IN 14 FB (4) ABSOLUTE MAXIMUM RATINGS (1) Thermal Resistance Supply Voltage VIN .......................................28V VSW ......................................–0.3V to VIN + 0.3V VBS ..................................................... VSW + 6V IVIN(RMS) ...........................................................3A ISW(RMS) ...........................................................3A All Other Pins................................ –0.3V to +6V (2) Continuous Power Dissipation (TA=+25°C ) ............................................................3.1W Junction Temperature.............................. 150°C Lead Temperature ................................... 260°C Storage Temperature.............. –65°C to +150°C Notes: 1) Exceeding these ratings may damage the device. 2) The maximum allowable power dissipation is a function of the maximum junction temperature TJ(MAX), the junction-toambient thermal resistance θJA, and the ambient temperature TA. The maximum allowable continuous power dissipation at any ambient temperature is calculated by PD(MAX)=(TJ(MAX)TA)/ θJA. Exceeding the maximum allowable power dissipation will cause excessive die temperature, and the regulator will go into thermal shutdown. Internal thermal shutdown circuitry protects the device from permanent damage. 3) The device is not guaranteed to function outside of its operating conditions. 4) Measured on JESD51-7, 4-layer PCB. Recommended Operating Conditions θJA θJC 4x5 QFN28..............................40.......9 °C/W (3) Supply Voltage VIN .......................... 5.5V to 25V Output Voltage VOUT........................ 0.8V to 15V Operating Junct. Temp (TJ)..... –20°C to +125°C NB621 Rev. 1.0 1/21/2014 www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2014 MPS. All Rights Reserved. 2 NB621 – 8A, 25V, 600kHz SYNCHRONOUS STEP-DOWN CONVERTER WITH INTEGRATED LDO ELECTRICAL CHARACTERISTICS VIN = 12V, TA = +25°C, unless otherwise noted. Parameters Symbol Supply Current (Shutdown) Supply Current (Quiescent) (5) High Side Switch On Resistance Switch Leakage (5) Current Limit Oscillator Frequency IIN IIN HSW RDS-ON SW LKG ILIMIT FSW Fold-back Frequency Maximum Duty Cycle Sync Frequency Range Feedback Voltage Feedback Current Soft Start Charging Current FFB DMAX FSYNC VFB IFB ISS EN/SYNC Input Low Voltage EN/SYNC Input High Voltage VILEN VIHEN EN Input Current (5) Power Good Delay Power Good Sink Current Capability Power Good Leakage Current VIN Under Voltage Lockout Threshold Rising VIN Under Voltage Lockout Threshold Hysteresis VCC Under Voltage Lockout Threshold Rising VCC Under Voltage Lockout Threshold Hysteresis VCC Regulator VCC Load Regulation NB621 Rev. 1.0 1/21/2014 Min VENLDO = 0V VEN = 2V, VFB = 1V VEN = 0V, VSW = 0V Typ Max Units 30 1.3 50 0 TBD TBD μA mA mΩ μA A kHz 10 9.5 VFB = 0.75V 600 VFB = 100mV VFB = 700mV 0.25 90 85 0.3 788 VFB = 800mV VSS=0V 808 10 10 2 828 50 0.4 2 VEN = 2V VEN = 0V fSW % MHz mV nA μA V V ENTd-Off PGVth-Hi PGVth-Lo 2 0 5 0.9 0.7 μsec VFB VFB PGTd 0.42 Tss IEN EN Turn Off Delay Power Good Threshold Rising Power Good Threshold Falling Condition μA (6) VPG Sink 4mA 0.4 V IPG_LEAK VPG = 3.3V 10 nA INUVVth VENLDO=open 5.06 V INUVHYS VENLDO=open 450 mV VCCUVVth VENLDO=open VCCUVHYS VENLDO=open VCC 3.8 4.5 ICC=20mA 4.0 4.2 V 880 mV 5 5 V % www.MonolithicPower.com MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2014 MPS. All Rights Reserved. 3 NB621 – 8A, 25V, 600kHz SYNCHRONOUS STEP-DOWN CONVERTER WITH INTEGRATED LDO ELECTRICAL CHARACTERISTICS (continued) VIN = 12V, TA = +25°C, unless otherwise noted. Parameters Symbol (5) LDD Switch On Resistance LDO Output Voltage LDO Output Current Switch Over Threshold (Rising) RLDO VLDO ILDO VSWO Switch Over Hysteresis VSWO-HYS SELH Input Low Voltage SELH Input High Voltage ENLDO Input Low Voltage VILENLDO ENLDO Input High Voltage VIHENLDO Thermal Shutdown VILSELH VIHSELH Condition VLDO=5V, ILDO=100mA SELH=0V, ILDO