SiC403 Vishay Siliconix microBUCK SiC403 6 A, 28 V Integrated Buck Regulator with Programmable LDO DESCRIPTION FEATURES High efficiency > 95 % The Vishay Siliconix SiC403 is an advanced stand-alone synchronous buck regulator featuring integrated power 6 A continuous output current capability MOSFETs, bootstrap switch, and a programmable LDO in a Integrated bootstrap switch space-saving MLPQ 5 x 5 - 32 pin package. Programmable 200 mA LDO with bypass logic The SiC403 is capable of operating with all ceramic solutions Temperature compensated current limit and switching frequencies up to 1 MHz. The programmable Pseudo fixed-frequency adaptive on-time control frequency, synchronous operation and selectable All ceramic solution enabled power-save allow operation at high efficiency across the full range of load current. The internal LDO may be used to Programmable input UVLO threshold supply 5 V for the gate drive circuits or it may be bypassed Independent enable pin for switcher and LDO with an external 5 V for optimum efficiency and used to drive Selectable ultra-sonic power-save mode external n-channel MOSFETs or other loads. Additional Programmable soft-start features include cycle-by-cycle current limit, voltage Soft-shutdown soft-start, under-voltage protection, programmable 1 % internal reference voltage over-current protection, soft shutdown and selectable power-save. The Vishay Siliconix SiC403 also provides an Power good output enable input and a power good output. Under and over voltage protection Material categorization: For definitions of compliance please see www.vishay.com/doc 99912 PRODUCT SUMMARY Input Voltage Range 3 V to 28 V APPLICATIONS Output Voltage Range 0.75 V to 5.5 V Notebook, desktop, and server computers Operating Frequency 200 kHz to 1 MHz Digital HDTV and digital consumer applications Continuous Output Current 6 A Networking and telecommunication equipment Peak Efficiency 95 % at 300 kHz Printers, DSL, and STB applications Package MLPQ 5 mm x 5 mm Embedded applications Point of load power supplies TYPICAL APPLICATION CIRCUIT 3.3 V EN/PSV (Tri-State) PGOOD LDO EN V OUT 32 31 30 29 28 27 26 25 V OUT LX FB 1 24 V OUT PAD 1 LX 2 23 V P DD GND A 3 GND 22 A P GND GND PAD 3 4 21 P FBL GND 5 LX 20 V IN PAD 2 V P IN GND 19 6 SS P V GND IN 7 18 BST P GND 8 17 SiC403 (MLP 5 x 5-32L) Document Number: 66550 For technical support, please contact: analogswitchtechsupport vishay.com www.vishay.com S12-0628-Rev. C, 19-Mar-12 1 This document is subject to change without notice. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc 91000 V ENL IN 9 V T IN ON 10 A V GND IN 11 EN PSV NC 12 LX LX 13 I LIM NC 14 P P GND GOOD 15 P GND LX 16SiC403 Vishay Siliconix PIN CONFIGURATION (TOP VIEW) 32 31 30 29 28 27 26 25 LX FB 1 24 PAD 1 V OUT 2 23 LX A V 3 GND DD 22 P GND PAD 3 A 4 21 GND P GND FBL LX 5 20 P GND PAD 2 V IN 6 19 P GND V IN SS 7 18 P GND P 17 GND BST 8 PIN DESCRIPTION Pin Number Symbol Description Feedback input for switching regulator. Connect to an external resistor divider from output to program 1FB output voltage. 2V Output voltage input to the controller. Additionally may be used to by pass LDO to supply V directly. OUT DD Bias for internal logic circuitry and gate drivers. Connect to external 5V power supply or configure 3V DD the internal LDO for 5 V. 4, 30, PAD 1 A Analog ground GND Feedback input for internal LDO. Connect to an external resistor divider from V to A to program DD GND 5FBL LDO output. 6, 9-11, PAD 2 V Power stage input (HS FET Drain) IN 7 SS Connect to an external capacitor to A to program softstart ramp GND 8 BST Bootstrap pin. A capacitor is connected between BST and LX to provide HS driver voltage. 12 NC Not internally connected 13, 23-25, 28, PAD 3 LX Switching node (HS FET Source and LS FET Drain) 14 NC Not internally connected 15-22 P Power ground (LS FET Source) GND 26 P Open-drain power good indicator. Externally pull-up resistor is required. GOOD 27 I Connect to an external resistor between I and LX to program over current limit LIM LIM Tri-state pin. Pull low to A to disable the regulator. Float to enable forced continuous current GND 29 EN/PSV mode. Pull high to V to enable power save mode. DD 31 T Connect to an external resistor to A program on-time ON GND 32 ENL Enable input for internal LDO. Pull down to A to disable internal LDO. GND ORDERING INFORMATION Part Number Package SiC403CD-T1-GE3 MLPQ55-32 SiC403DB Evaluation board www.vishay.com For technical support, please contact: analogswitchtechsupport vishay.com Document Number: 66550 2 S12-0628-Rev. C, 19-Mar-12 This document is subject to change without notice. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc 91000 ENL V 9 IN V TON IN 10 V A IN 11 GND NC 12 EN PSV LX 13 LX I NC 14 LIM P GND 15 P GOOD LX P 16 GND