MP4423HGQ-Z

MP4423H High Efficiency 3A, 36V, Synchronous Step Down Converter The Future of Analog IC Technology DESCRIPTION FEATURES The MP4423H is a high-frequency, synchronous, rectified, step-down, switch-mode converter with built-in power MOSFETs. It offers a very compact solution to achieve a 3A continuous output current with excellent load and line regulation over a wide input supply range. The MP4423H has synchronous mode operation for higher efficiency over the output current load range. • Current-mode operation provides fast transient response and eases loop stabilization. • • • • • • • • Full protection features include over-current protection and thermal shut down. The MP4423H requires a minimal number of readily-available standard external components, and is available in a space-saving QFN-8 (3mmx3mm) package. • • • • Wide 4V to 36V Continuous Operating Input Range 85mΩ/55mΩ Low RDS(ON) Internal Power MOSFETs High-Efficiency Synchronous Mode Operation Default 410kHz Switching Frequency Synchronizes to a 200kHz to 2.2MHz External Clock High Duty Cycle for Automotive Cold-crank Power-Save Mode Internal Soft-Start Power Good OCP Protection and Hiccup Thermal Shutdown Output Adjustable from 0.8V Available in an QFN-8 (3mmx3mm) package APPLICATIONS • • • Automotive Industrial Control System Distributed Power Systems All MPS parts are lead-free and adhere to the RoHS directive. For MPS green status, please visit MPS website under Quality Assurance. “MPS” and “The Future of Analog IC Technology” are Registered Trademarks of Monolithic Power Systems, Inc. TYPICAL APPLICATION MP4423H Rev. 1.0 www.MonolithicPower.com 8/18/2014 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2014 MPS. All Rights Reserved. 1 MP4423H – 36V, 3A SYNCHRONOUS STEP-DOWN CONVERTER ORDERING INFORMATION Part Number* MP4423HGQ Package QFN-8 (3mmx3mm) Top Marking See Below * For Tape & Reel, add suffix –Z (e.g. MP4423HGQ–Z) TOP MARKING ALN: product code of MP4423HGQ; Y: year code; LLL: lot number; PACKAGE REFERENCE TOP VIEW FB 1 8 PG VCC 2 7 IN EN/SYNC 3 6 SW BST 4 5 GND QFN-8 (3mmx3mm) MP4423H Rev. 1.0 www.MonolithicPower.com 8/18/2014 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2014 MPS. All Rights Reserved. 2 MP4423H – 36V, 3A SYNCHRONOUS STEP-DOWN CONVERTER ABSOLUTE MAXIMUM RATINGS (1) Thermal Resistance VIN ................................................ -0.3V to 40V VSW ................................................ -0.3V to 41V VBS ....................................................... VSW+6V All Other Pins ................................ -0.3V to 6V (2) (3) Continuous Power Dissipation (TA = +25°C) QFN-8 (3mmx3mm) ................................. 2.27W Junction Temperature .............................. 150°C Lead Temperature ................................... 260°C Storage Temperature ................. -65°C to 150°C QFN-8 (3mmx3mm) .............. 55 ...... 13 ... °C/W Recommended Operating Conditions Continuous Supply Voltage VIN .......... 4V to 36V Output Voltage VOUT................... 0.8V to 0.9xVIN Operating Junction Temp. (TJ). -40°C to +125°C (4) θJA θJC Notes: 1) Absolute maximum ratings are rated under room temperature unless otherwise noted. Exceeding these ratings may damage the device. 2) About the details of EN pin’s ABS MAX rating, please refer to page 12, Enable/SYNC Control section. 3) 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. 4) Measured on JESD51-7, 4-layer PCB. MP4423H Rev. 1.0 www.MonolithicPower.com 8/18/2014 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2014 MPS. All Rights Reserved. 3 MP4423H – 36V, 3A SYNCHRONOUS STEP-DOWN CONVERTER ELECTRICAL CHARACTERISTICS VIN = 12V, TJ = +25°C, unless otherwise noted. Parameter Symbol Supply Current (Shutdown) ISHDN Supply Current (Quiescent) IQ HS Switch-ON Resistance Condition Min Typ VEN = 0V Max Units 8 μA VEN = 2V, VFB = 1V 0.5 0.7 mA RON_HS VBST-SW =5V 85 105 mΩ LS Switch-ON Resistance RON_LS VCC =5V 55 75 mΩ Switch Leakage ILKG VEN = 0V, VSW =12V 1 μA Current Limit SW ILIMIT Under 40% Duty Cycle 3.2 4.4 5.5 A fSW VFB=750mV 320 410 500 kHz Fold-Back Frequency fFB VFB65%). A power supply between 2.5V and 5V can be used to power the external bootstrap diode and VCC or VOUT is the good choice of this power supply in the circuit as shown in Figure 6. VCC External BST diode 1N4148 BST VCC/V OUT R BST C BST L SW VOUT C OUT Figure 6: Optional External Bootstrap Diode to Enhance Efficiency The recommended external BST diode is IN4148, and the BST capacitor value is 0.1µF to 1μF. MP4423H Rev. 1.0 www.MonolithicPower.com 8/18/2014 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2014 MPS. All Rights Reserved. 15 MP4423H – 36V, 3A SYNCHRONOUS STEP-DOWN CONVERTER PCB Layout PCB layout, especially the input capacitor and VCC capacitor placement, is very important to achieve stable operation. For the best results, follow these guidelines: 1) Place the ceramics input capacitor as close to IN and GND pins as possible, especially the small package size (0603) input bypass capacitor. Keep the connection of input capacitor and IN pin as short and wide as possible. 2) Place the VCC capacitor to VCC pin and GND pin as close as possible. Make the trace length of VCC pin-VCC capacitor anode-VCC capacitor cathode-chip GND pin as short as possible. 3) Use large ground plane directly connect to GND pin. Add vias near the GND pin if bottom layer is ground plane. 4) Route SW, BST away from sensitive analog areas such as FB. 5) Place the T-type feedback resistor close to chip to ensure the trace which connects to FB pin as the short as possible. Top Layer Bottom Layer Figure 7: Recommended PCB Layout MP4423H Rev. 1.0 www.MonolithicPower.com 8/18/2014 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2014 MPS. All Rights Reserved. 16 MP4423H – 36V, 3A SYNCHRONOUS STEP-DOWN CONVERTER TYPICAL APPLICATION CIRCUITS Figure 8: 3.3V Output Typical Application Circuit MP4423H Rev. 1.0 www.MonolithicPower.com 8/18/2014 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2014 MPS. All Rights Reserved. 17 MP4423H – 36V, 3A SYNCHRONOUS STEP-DOWN CONVERTER PACKAGE INFORMATION QFN-8 (3mmx3mm) NOTICE: The information in this document is subject to change without notice. Users should warrant and guarantee that third party Intellectual Property rights are not infringed upon when integrating MPS products into any application. MPS will not assume any legal responsibility for any said applications. MP4423H Rev. 1.0 www.MonolithicPower.com 8/18/2014 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2014 MPS. All Rights Reserved. 18