NCP81274 8/7/6/5/4/3/2/1 Phase Buck Controller with PWM VID 2 and I C Interface The NCP81274 is a multiphase synchronous controller optimized www.onsemi.com for new generation computing and graphics processors. The device is capable of driving up to 8 phases and incorporates differential voltage and phase current sensing, adaptive voltage positioning and PWM VID interface to provide and accurately regulated power for computer or graphic controllers. The integrated power saving 1 40 interface (PSI) allows for the processors to set the controller in one of QFN40 three modes, i.e. all phases on, dynamic phases shedding or fixed low CASE 485CR phase count mode, to obtain high efficiency in light-load conditions. The dual edge PWM multiphase architecture ensures fast transient MARKING DIAGRAM response and good dynamic current balance. 1 Features ON NCP Compliant with NVIDIA OVR4+ Specifications 81274 Supports Up to 8 Phases AWLYYWW 4.5 V to 20 V Supply Voltage Range 250 kHz to 1.2 MHz Switching Frequency (8 Phase) NCP81274 = Specific Device Code Power Good Output A = Assembly Location WL = Wafer Lot Under Voltage Protection (UVP) YY = Year Over Voltage Protection (OVP) WW = Work Week = Pb-Free Package Over Current Protection (OCP) (Note: Microdot may be in either location) Per Phase Over Current Protection Startup into Pre-Charged Loads while Avoiding False OVP PIN CONNECTIONS Configurable Adaptive Voltage Positioning (AVP) High Performance Operational Error Amplifier True Differential Current Balancing Sense Amplifiers for Each Phase REFIN 1 30 COMP 2 29 VREF FB Phase-to-Phase Dynamic Current Balancing 3 28 DIFF VRMP PWM8/SS 4 27 FSW Current Mode Dual Edge Modulation for Fast Initial Response to NCP81274 5 26 PWM7/OCP LLTH/I2C ADD Transient Loading (TOP VIEW) 6 25 IOUT PWM6/LPC1 7 24 PWM5/LPC2 ILIM Power Saving Interface (PSI) Tab: GROUND 8 23 PWM4/PHTH1 CSCOMP Automatic Phase Shedding with User Settable Thresholds 9 22 PWM3/PHTH2 CSSUM 10 21 CSREF PWM2/PHTH3 2 PWM VID and I C Control Interface Compact 40 Pin QFN Package (5 5 mm Body, 0.4 mm Pitch) This Device is Pb-Free and is RoHS Compliant Typical Applications ORDERING INFORMATION GPU and CPU Power Device Package Shipping Graphic Cards NCP81274MNTXG QFN40 5000/Tape & Reel Desktop and Notebook Applications (Pb-Free) For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging Specification Brochure, BRD8011/D. Semiconductor Components Industries, LLC, 2017 1 Publication Order Number: June, 2017 Rev. 15 NCP81274/D PWM1/ 40 PHTH4 11 VID BUFF 12 39 PWM VID DRON 13 38 PGOOD CSP8 14 37 CSP7 PSI CSP6 15 36 EN 16 35 CSP5 SCL 17 34 CSP4 SDA 18 33 CSP3 VCC 32 VSN CSP2 19 20 31 VSP CSP1NCP81274 Figure 1. Typical Controller Application Circuit www.onsemi.com 2 TP45 TP46 TP47 TP48 TP49 TP50 TP51 VCC DUT VSN sense J4 R38 SDA 2.2R SCL C5 J3 C17 EN 1000pF 1uF PSI PWM VID in PGOOD J1 TP1 C2 VSP sense R37 TP52 TP53 TP54 TP36 TP44 4.7nF 6.19k TP37 R16 REFIN R21 TP42 C18 309R C15 16.5k R43 R49 U1 R9 TP38 C3 TP43 9.69k VIN 49.9R 2.2nF 680pF TP39 1k 4.7nF C16 TP55 TP57 TP58 TP59 R48 TP56 C4 1 30 TP41 REFIN COMP 68pF C1 VREF 1k 10nF 2 29 TP40 0.01uF VREF FB 3 28 VRAMP DIFF 4 27 PWM8 PWM8/SS FSW 5 26 PWM7 PWM7/OCP LLTH/I2C ADD NCP81274 6 25 PWM6 PWM6/LPC1 IOUT 7 24 PWM5 PWM5/LPC2 ILIM 8 23 PWM4 PWM4/PHTH1 CSCOMP 9 22 PWM3 PWM3/PHTH2 CSSUM 10 21 PWM2/PHTH3 CSREF PWM2 PWM1 41 C13 PWM1/PHTH4 PAD 390nF R22 R18 R10 R14 TP62 R7 R13 R2 R4 1k 33k 68k 10k 1k 10k 10k 10k C6 DRON 0.1uF R1DNP 1 VCC DUT DNP R3 C7 0.1uF DNP R5 C8 0.1uF TP60 R6DNP C9 0.1uF DNP R8 C10 0.1uF R11DNP C11 0.1uF DNP C12 0.1uF R12 C14 TP61 0.1uF R30 215k R29 215k R31 215k R33 215k R34 215k R35 215k R36 215k R32 215k R152k32 SWN8 R17 2k32 SWN7 R192k32 SWN6 R202k32 2 SWN5 R232k32 SWN4 2k32 R24 R25 SWN3 4.32k R26 2k32 SWN2 2k32 R27 R28 SWN1 20.5k 11 40 VID BUFF 12 39 DRON PWM VID 13 38 CSP8 PGOOD 14 37 CSP7 PSI 15 36 CSP6 EN 16 35 CSP5 SCL 17 34 CSP4 SDA 18 33 CSP3 VCC 19 32 CSP2 VSN 20 31 CSP1 VSP 0R R142 R39 CSN8 R143 0R R40 10R CSN7 10R R144 0R R41 CSN6 10R R42 R145 0R CSN5 10R R44 R146 0R CSN4 10R R R45 R147 0 CSN3 10R R1480R R46 CSN2 10R R149 0R R47 CSN1 10R R51 R50 75k 165k RT1 220k 1000pF C19 R1270R R54 51k 36pF C20 R1260R R55 47k C21 470pF R124 10k 0R R56 R57 26.1k R1250R 1