BOOT P GND A P GND GOOD f EN SW SiC476, SiC477, SiC478, SiC479 www.vishay.com Vishay Siliconix 4.5 V to 55 V Input, 3 A, 5 A, 8 A, 12 A microBUCK DC/DC Converter FEATURES Versatile - Single supply operation from 4.5 V to 55 V input voltage - Adjustable output voltage down to 0.8 V - Scalable solution 3 A (SiC479), 5 A (SiC478), 8 A (SiC477), 12 A (SiC476) - Output voltage tracking and sequencing with pre-bias start up - 1 % output voltage accuracy at -40 C to +125 C Internal compensation Highly efficient LINKS TO ADDITIONAL RESOURCES - 98 % peak efficiency - 4 A supply current at shutdown - 156 A operating current not switching Design Tool Evaluation Design Tools Highly configurable Boards - Adjustable switching frequency from 100 kHz to 2 MHz DESCRIPTION - Adjustable soft start and selectable preset 100 %, 75 %, and 50 % current limit The SiC47x is a family of wide input voltage high efficiency - 2 modes of operation, forced continuous conduction or synchronous buck regulators with integrated high side and power save mode low side power MOSFETs. Its power stage is capable of Robust and reliable supplying high continuous current at up to 2 MHz switching - Output over voltage protection frequency. This regulator produces an adjustable output - Output under voltage / short circuit protection with auto voltage down to 0.8 V from 4.5 V to 55 V input rail retry to accommodate a variety of applications, includin g - Power good flag and over temperature protection - Supported by Vishay PowerCAD online design computing, consumer electronics, telecom, and industrial. simulation SiC47xs architecture delivers ultrafast transient response Material categorization: for definitions of compliance with minimum output capacitance and tight ripple regulation please see www.vishay.com/doc 99912 at very light load. The device is internally compensated and APPLICATIONS is stable with any capacitor. No external ESR network is Industrial and automation required for loop stability purpose. The device also Home automation incorporates a power saving scheme that significantly Industrial and server computing increases light load efficiency. The regulator integrates a full Networking, telecom, and base station power supplies protection feature set, including over current protection Wall transformer regulation Robotics (OCP), output overvoltage protection (OVP), short circuit High end hobby electronics: remote control cars, planes, protection (SCP), output undervoltage protection (UVP) and and drones thermal shutdown (OTP). It also has UVLO for input rail and Battery management systems a user programmable soft start. Power tools Vending, ATM, and slot machines The SiC47x family is available in 3 A, 5 A, 8 A, 12 A pin compatible 5 mm by 5 mm lead (Pb)-free power enhanced Axis Title MLP55-27L package. 100 10000 V = 24 V, V = 12 V IN OUT 98 TYP ICAL APPLICATION CIRCUIT 96 94 C 1000 BOOT Input V CIN 92 Phase V 4.5 V to 60 V OUT DC DC V = 48 V, V = 12 V IN OUT SW V IN SiC476 90 SiC477 V V = 24 V, V = 5 V DD IN OUT C SiC478 IN V V OUT 88 DRV SiC479 R NC SS up 100 86 V I FB C OUT LIMIT MODE NC R down 84 C ss V = 48 V, V = 5 V IN OUT 82 R MODE 80 10 R fsw 012345678 I - Output Current (A) OUT Fig. 1 - Typical Application Circuit Fig. 2 - SiC477 Efficiency vs. Output Current S21-0231-Rev. E, 15-Mar-2021 Document Number: 77113 1 For technical questions, contact: powerictechsupport vishay.com 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 2nd line eff - Efficiency (%) 1st line 2nd line SiC476, SiC477, SiC478, SiC479 www.vishay.com Vishay Siliconix PIN CONFIGURATION V 1 1 V CIN 19 SS SS 19 CIN 28 A GND 18 NC NC 18 P 28 AGND 2 GOOD 2 P GOOD 17 P P 17 GND GND EN 3 3 EN 16 V V 16 DRV DRV BOOT 4 4 BOOT 15 GL GL 15 30 14 SW SW 14 29 PHASE VIN 5 29 PGND 5 PHASE V 30 P IN 13 SW SW 13 GND PHASE 6 6 PHASE 12 SW SW 12 Fig. 3 - Pin Configuration PIN DESCRIPTION PIN NUMBER SYMBOL DESCRIPTION Supply voltage for internal regulators V and V . This pin should be tied to V , but can also be DD DRV IN 1V CIN connected to a lower supply voltage (> 5 V) to reduce losses in the internal linear regulators Open-drain power good indicator - high impedance indicates power is good. An external pull-up 2P GOOD resistor is required Enable pin. Tie high / low to enable / disable the IC accordingly. This is a high voltage compatible pin, 3EN can be tied to 55 V 4 BOOT High side driver bootstrap voltage 5, 6 PHASE Return path of high side gate driver 7, 8, 29 V Power stage input voltage. Drain of high side MOSFET IN 9, 10, 11, 17, 30 P Power ground GND 12, 13, 14 SW Power stage switch node 15 GL Low side MOSFET gate signal Supply voltage for internal gate driver. When using the internal LDO as a bias power supply, V is DRV 16 V DRV the LDO output. Connect a 4.7 F decoupling capacitor to P GND 18, 21 NC No connection internally Set the soft start ramp by connecting a capacitor to A . An internal current source will charge the GND 19 SS capacitor 20 V Output voltage sense point for internal ripple injection components OUT Feedback input for switching regulator used to program the output voltage - connect to an external 22 V FB resistor divider from V to A OUT GND 23, 28 A Analog ground GND 24 f Set the on-time by connecting a resistor to A SW GND 25 I Set the current limit by connecting I pin to A , float or V LIMIT LIMIT GND DD 26 V Bias supply for the IC. V is an LDO output, connect a 1 F decoupling capacitor to A DD DD GND 27 Mode Set various operation modes by connecting a resistor to A . See specification table for details GND S21-0231-Rev. E, 15-Mar-2021 Document Number: 77113 2 For technical questions, contact: powerictechsupport vishay.com 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 27 MODE V 7 IN 26 V DD V 8 IN I 25 LIM f 24 SW P 9 23 A GND GND 22 V P 10 FB GND P 11 21 NC GND 20 V OUT 20 V OUT P 11 21 NC GND P 10 22 V GND FB P 9 23 A GND GND 24 f SW 25 I LIM V 8 IN 26 V DD V 7 IN 27 MODE