RT8172AGQW

® RT8172A Dual Single-Phase PWM Controller for CPU and GPU Core Power Supply General Description The RT8172A is a dual single-phase PWM controller with integrated MOSFET drivers, compliant with Intel IMVP7 Pulse Width Modulation Specification to support both CPU core and GPU core power. This part adopts G-NAVPTM (Green-Native AVP), which is Richtek's proprietary topology derived from finite DC gain compensator in constant ontime control mode. The G-NAVPTM makes this part an easy setting PWM controller to meet all Intel AVP (Active Voltage Positioning) mobile CPU/GPU requirements. The RT8172A uses SVID interface to control an 8-bit DAC for output voltage programming. The built-in high accuracy DAC converts the received VID code into a voltage value ranging from 0V to 1.52V with 5mV step voltage. The system accuracy of the controller can reach 0.8%. The RT8172A operates in continuous conduction mode or diode emulation mode, according to the SVID command. The maximum efficiency can reach up to 90% in different operating modes according to different load conditions. The droop function (load line) can be easily programmed by setting the DC gain of the error amplifier. With proper compensation, the load transient response can achieve optimized AVP performance. The output voltage transition slew rate is set via the SVID interface. The RT8172A supports both DCR and sense resistor current sensing. The RT8172A provides VR_READY and thermal throttling output signals for IMVP7 CPU and GPU core. This part also features complete fault protection functions including over-voltage, under-voltage, negative-voltage, over-current and thermal shutdown. The RT8172A is available in the WQFN-40L 5x5 small footprint package. Features                 Dual Single-Phase PWM Controller for CPU Core and GPU Core Power IMVP7 Compatible Power Management States Serial VID Interface G-NAVPTM Topology AVP for CPU VR Only 0.5% DAC Accuracy 0.8% System Accuracy Differential Remote Voltage Sensing Built-in ADC for Platform Programming  SETINI/SETINIA for CPU/GPU Core VR Initial Startup Voltage  TMPMAX to Set Platform Maximum Temperature  ICCMAX/ICCMAXA for CPU/GPU Core VR Maximum Current Power Good Indicator : VR_READY/VRA_READY for CPU/GPU Core Power Thermal Throttling Indicator : VRHOT Diode Emulation Mode at Light Load Condition Fast Line/Load Transient Response Switching Frequency up to 1MHz per Phase OVP, UVP, NVP, OTP, UVLO, OCP RoHS Compliant and Halogen Free Simplified Application Circuit VR_READY VRA_READY VRHOT VCLK VDIO ALERT RT8172A VR_READY VRA_READY PHASE VRHOT VCLK PHASEA VDIO ALERT Copyright © 2013 Richtek Technology Corporation. All rights reserved. DS8172A-00 November 2013 MOSFET VCORE MOSFET VGPU is a registered trademark of Richtek Technology Corporation. www.richtek.com 1 RT8172A Applications  Ordering Information RT8172A Package Type QW : WQFN-40L 5x5 (W-Type) Lead Plating System G : Green (Halogen Free and Pb Free) Note : Richtek products are :  RoHS compliant and compatible with the current requirements of IPC/JEDEC J-STD-020.  Suitable for use in SnPb or Pb-free soldering processes. UGATE1 PHASE1 LGATE1 PVCC LGATEA PHASEA UGATEA BOOTA EN TONSETA  (TOP VIEW) IMVP7 Intel CPU/GPU Core Power Supply Laptop Computers AVP Step-Down Converter 40 39 38 37 36 35 34 33 32 31 BOOT1 TONSET ISEN1P ISEN1N COMP FB RGND GFXPS2 VCC SETINI 1 30 2 29 3 28 4 27 5 26 GND 25 6 24 7 8 41 23 22 9 21 10 ISENAP ISENAN COMPA FBA RGNDA VCLK VDIO ALERT VRA_READY VR_READY 11 12 13 14 15 16 17 18 19 20 SETINIA TMPMAX ICCMAX ICCMAXA TSEN OCSET TSENA OCSETA IBIAS VRHOT  Pin Configurations WQFN-40L 5x5 Marking Information RT8172AGQW : Product Number RT8172A GQW YMDNN YMDNN : Date Code Copyright © 2013 Richtek Technology Corporation. All rights reserved. www.richtek.com 2 is a registered trademark of Richtek Technology Corporation. DS8172A-00 November 2013 RT8172A Table 1. IMVP7/VR12 Compliant VID Table VID7 VID6 VID5 VID4 VID3 VID2 VID1 VID0 H1 H0 VDAC Voltage 0 0 0 0 0 0 0 0 0 0 0.000 0 0 0 0 0 0 0 1 0 1 0.250 0 0 0 0 0 0 1 0 0 2 0.255 0 0 0 0 0 0 1 1 0 3 0.260 0 0 0 0 0 1 0 0 0 4 0.265 0 0 0 0 0 1 0 1 0 5 0.270 0 0 0 0 0 1 1 0 0 6 0.275 0 0 0 0 0 1 1 1 0 7 0.280 0 0 0 0 1 0 0 0 0 8 0.285 0 0 0 0 1 0 0 1 0 9 0.290 0 0 0 0 1 0 1 0 0 A 0.295 0 0 0 0 1 0 1 1 0 B 0.300 0 0 0 0 1 1 0 0 0 C 0.305 0 0 0 0 1 1 0 1 0 D 0.310 0 0 0 0 1 1 1 0 0 E 0.315 0 0 0 0 1 1 1 1 0 F 0.320 0 0 0 1 0 0 0 0 1 0 0.325 0 0 0 1 0 0 0 1 1 1 0.330 0 0 0 1 0 0 1 0 1 2 0.335 0 0 0 1 0 0 1 1 1 3 0.340 0 0 0 1 0 1 0 0 1 4 0.345 0 0 0 1 0 1 0 1 1 5 0.350 0 0 0 1 0 1 1 0 1 6 0.355 0 0 0 1 0 1 1 1 1 7 0.360 0 0 0 1 1 0 0 0 1 8 0.365 0 0 0 1 1 0 0 1 1 9 0.370 0 0 0 1 1 0 1 0 1 A 0.375 0 0 0 1 1 0 1 1 1 B 0.380 0 0 0 1 1 1 0 0 1 C 0.385 0 0 0 1 1 1 0 1 1 D 0.390 0 0 0 1 1 1 1 0 1 E 0.395 0 0 0 1 1 1 1 1 1 F 0.400 0 0 1 0 0 0 0 0 2 0 0.405 0 0 1 0 0 0 0 1 2 1 0.410 0 0 1 0 0 0 1 0 2 2 0.415 Copyright © 2013 Richtek Technology Corporation. All rights reserved. DS8172A-00 November 2013 is a registered trademark of Richtek Technology Corporation. www.richtek.com 3 RT8172A VID7 VID6 VID5 VID4 VID3 VID2 VID1 VID0 H1 H0 DAC Voltage 0 0 1 0 0 0 1 1 2 3 0.420 0 0 1 0 0 1 0 0 2 4 0.425 0 0 1 0 0 1 0 1 2 5 0.430 0 0 1 0 0 1 1 0 2 6 0.435 0 0 1 0 0 1 1 1 2 7 0.440 0 0 1 0 1 0 0 0 2 8 0.445 0 0 1 0 1 0 0 1 2 9 0.450 0 0 1 0 1 0 1 0 2 A 0.455 0 0 1 0 1 0 1 1 2 B 0.460 0 0 1 0 1 1 0 0 2 C 0.465 0 0 1 0 1 1 0 1 2 D 0.470 0 0 1 0 1 1 1 0 2 E 0.475 0 0 1 0 1 1 1 1 2 F 0.480 0 0 1 1 0 0 0 0 3 0 0.485 0 0 1 1 0 0 0 1 3 1 0.490 0 0 1 1 0 0 1 0 3 2 0.495 0 0 1 1 0 0 1 1 3 3 0.500 0 0 1 1 0 1 0 0 3 4 0.505 0 0 1 1 0 1 0 1 3 5 0.510 0 0 1 1 0 1 1 0 3 6 0.515 0 0 1 1 0 1 1 1 3 7 0.520 0 0 1 1 1 0 0 0 3 8 0.525 0 0 1 1 1 0 0 1 3 9 0.530 0 0 1 1 1 0 1 0 3 A 0.535 0 0 1 1 1 0 1 1 3 B 0.540 0 0 1 1 1 1 0 0 3 C 0.545 0 0 1 1 1 1 0 1 3 D 0.550 0 0 1 1 1 1 1 0 3 E 0.555 0 0 1 1 1 1 1 1 3 F 0.560 0 1 0 0 0 0 0 0 4 0 0.565 0 1 0 0 0 0 0 1 4 1 0.570 0 1 0 0 0 0 1 0 4 2 0.575 0 1 0 0 0 0 1 1 4 3 0.580 0 1 0 0 0 1 0 0 4 4 0.585 0 1 0 0 0 1 0 1 4 5 0.590 Copyright © 2013 Richtek Technology Corporation. All rights reserved. www.richtek.com 4 is a registered trademark of Richtek Technology Corporation. DS8172A-00 November 2013 RT8172A VID7 VID6 VID5 VID4 VID3 VID2 VID1 VID0 H1 H0 DAC Voltage 0 1 0 0 0 1 1 0 4 6 0.595 0 1 0 0 0 1 1 1 4 7 0.600 0 1 0 0 1 0 0 0 4 8 0.605 0 1 0 0 1 0 0 1 4 9 0.610 0 1 0 0 1 0 1 0 4 A 0.615 0 1 0 0 1 0 1 1 4 B 0.620 0 1 0 0 1 1 0 0 4 C 0.625 0 1 0 0 1 1 0 1 4 D 0.630 0 1 0 0 1 1 1 0 4 E 0.635 0 1 0 0 1 1 1 1 4 F 0.640 0 1 0 1 0 0 0 0 5 0 0.645 0 1 0 1 0 0 0 1 5 1 0.650 0 1 0 1 0 0 1 0 5 2 0.655 0 1 0 1 0 0 1 1 5 3 0.660 0 1 0 1 0 1 0 0 5 4 0.665 0 1 0 1 0 1 0 1 5 5 0.670 0 1 0 1 0 1 1 0 5 6 0.675 0 1 0 1 0 1 1 1 5 7 0.680 0 1 0 1 1 0 0 0 5 8 0.685 0 1 0 1 1 0 0 1 5 9 0.690 0 1 0 1 1 0 1 0 5 A 0.695 0 1 0 1 1 0 1 1 5 B 0.700 0 1 0 1 1 1 0 0 5 C 0.705 0 1 0 1 1 1 0 1 5 D 0.710 0 1 0 1 1 1 1 0 5 E 0.715 0 1 0 1 1 1 1 1 5 F 0.720 0 1 1 0 0 0 0 0 6 0 0.725 0 1 1 0 0 0 0 1 6 1 0.730 0 1 1 0 0 0 1 0 6 2 0.735 0 1 1 0 0 0 1 1 6 3 0.740 0 1 1 0 0 1 0 0 6 4 0.745 0 1 1 0 0 1 0 1 6 5 0.750 0 1 1 0 0 1 1 0 6 6 0.755 0 1 1 0 0 1 1 1 6 7 0.760 0 1 1 0 1 0 0 0 6 8 0.765 0 1 1 0 1 0 0 1 6 9 0.770 Copyright © 2013 Richtek Technology Corporation. All rights reserved. DS8172A-00 November 2013 is a registered trademark of Richtek Technology Corporation. www.richtek.com 5 RT8172A VID7 VID6 VID5 VID4 VID3 VID2 VID1 VID0 H1 H0 DAC Voltage 0 1 1 0 1 0 1 0 6 A 0.775 0 1 1 0 1 0 1 1 6 B 0.780 0 1 1 0 1 1 0 0 6 C 0.785 0 1 1 0 1 1 0 1 6 D 0.790 0 1 1 0 1 1 1 0 6 E 0.795 0 1 1 0 1 1 1 1 6 F 0.800 0 1 1 1 0 0 0 0 7 0 0.805 0 1 1 1 0 0 0 1 7 1 0.810 0 1 1 1 0 0 1 0 7 2 0.815 0 1 1 1 0 0 1 1 7 3 0.820 0 1 1 1 0 1 0 0 7 4 0.825 0 1 1 1 0 1 0 1 7 5 0.830 0 1 1 1 0 1 1 0 7 6 0.835 0 1 1 1 0 1 1 1 7 7 0.840 0 1 1 1 1 0 0 0 7 8 0.845 0 1 1 1 1 0 0 1 7 9 0.850 0 1 1 1 1 0 1 0 7 A 0.855 0 1 1 1 1 0 1 1 7 B 0.860 0 1 1 1 1 1 0 0 7 C 0.865 0 1 1 1 1 1 0 1 7 D 0.870 0 1 1 1 1 1 1 0 7 E 0.875 0 1 1 1 1 1 1 1 7 F 0.880 1 0 0 0 0 0 0 0 8 0 0.885 1 0 0 0 0 0 0 1 8 1 0.890 1 0 0 0 0 0 1 0 8 2 0.895 1 0 0 0 0 0 1 1 8 3 0.900 1 0 0 0 0 1 0 0 8 4 0.905 1 0 0 0 0 1 0 1 8 5 0.910 1 0 0 0 0 1 1 0 8 6 0.915 1 0 0 0 0 1 1 1 8 7 0.920 1 0 0 0 1 0 0 0 8 8 0.925 1 0 0 0 1 0 0 1 8 9 0.930 1 0 0 0 1 0 1 0 8 A 0.935 1 0 0 0 1 0 1 1 8 B 0.940 1 0 0 0 1 1 0 0 8 C 0.945 1 0 0 0 1 1 0 1 8 D 0.950 Copyright © 2013 Richtek Technology Corporation. All rights reserved. www.richtek.com 6 is a registered trademark of Richtek Technology Corporation. DS8172A-00 November 2013 RT8172A VID7 VID6 VID5 VID4 VID3 VID2 VID1 VID0 H1 H0 DAC Voltage 1 0 0 0 1 1 1 0 8 E 0.955 1 0 0 0 1 1 1 1 8 F 0.960 1 0 0 1 0 0 0 0 9 0 0.965 1 0 0 1 0 0 0 1 9 1 0.970 1 0 0 1 0 0 1 0 9 2 0.975 1 0 0 1 0 0 1 1 9 3 0.980 1 0 0 1 0 1 0 0 9 4 0.985 1 0 0 1 0 1 0 1 9 5 0.990 1 0 0 1 0 1 1 0 9 6 0.995 1 0 0 1 0 1 1 1 9 7 1.000 1 0 0 1 1 0 0 0 9 8 1.005 1 0 0 1 1 0 0 1 9 9 1.010 1 0 0 1 1 0 1 0 9 A 1.015 1 0 0 1 1 0 1 1 9 B 1.020 1 0 0 1 1 1 0 0 9 C 1.025 1 0 0 1 1 1 0 1 9 D 1.030 1 0 0 1 1 1 1 0 9 E 1.035 1 0 0 1 1 1 1 1 9 F 1.040 1 0 1 0 0 0 0 0 A 0 1.045 1 0 1 0 0 0 0 1 A 1 1.050 1 0 1 0 0 0 1 0 A 2 1.055 1 0 1 0 0 0 1 1 A 3 1.060 1 0 1 0 0 1 0 0 A 4 1.065 1 0 1 0 0 1 0 1 A 5 1.070 1 0 1 0 0 1 1 0 A 6 1.075 1 0 1 0 0 1 1 1 A 7 1.080 1 0 1 0 1 0 0 0 A 8 1.085 1 0 1 0 1 0 0 1 A 9 1.090 1 0 1 0 1 0 1 0 A A 1.095 1 0 1 0 1 0 1 1 A B 1.100 1 0 1 0 1 1 0 0 A C 1.105 1 0 1 0 1 1 0 1 A D 1.110 1 0 1 0 1 1 1 0 A E 1.115 1 0 1 0 1 1 1 1 A F 1.120 1 0 1 1 0 0 0 0 B 0 1.125 1 0 1 1 0 0 0 1 B 1 1.130 Copyright © 2013 Richtek Technology Corporation. All rights reserved. DS8172A-00 November 2013 is a registered trademark of Richtek Technology Corporation. www.richtek.com 7 RT8172A VID7 VID6 VID5 VID4 VID3 VID2 VID1 VID0 H1 H0 DAC Voltage 1 0 1 1 0 0 1 0 B 2 1.135 1 0 1 1 0 0 1 1 B 3 1.140 1 0 1 1 0 1 0 0 B 4 1.145 1 0 1 1 0 1 0 1 B 5 1.150 1 0 1 1 0 1 1 0 B 6 1.155 1 0 1 1 0 1 1 1 B 7 1.160 1 0 1 1 1 0 0 0 B 8 1.165 1 0 1 1 1 0 0 1 B 9 1.170 1 0 1 1 1 0 1 0 B A 1.175 1 0 1 1 1 0 1 1 B B 1.180 1 0 1 1 1 1 0 0 B C 1.185 1 0 1 1 1 1 0 1 B D 1.190 1 0 1 1 1 1 1 0 B E 1.195 1 0 1 1 1 1 1 1 B F 1.200 1 1 0 0 0 0 0 0 C 0 1.205 1 1 0 0 0 0 0 1 C 1 1.210 1 1 0 0 0 0 1 0 C 2 1.215 1 1 0 0 0 0 1 1 C 3 1.220 1 1 0 0 0 1 0 0 C 4 1.225 1 1 0 0 0 1 0 1 C 5 1.230 1 1 0 0 0 1 1 0 C 6 1.235 1 1 0 0 0 1 1 1 C 7 1.240 1 1 0 0 1 0 0 0 C 8 1.245 1 1 0 0 1 0 0 1 C 9 1.250 1 1 0 0 1 0 1 0 C A 1.255 1 1 0 0 1 0 1 1 C B 1.260 1 1 0 0 1 1 0 0 C C 1.265 1 1 0 0 1 1 0 1 C D 1.270 1 1 0 0 1 1 1 0 C E 1.275 1 1 0 0 1 1 1 1 C F 1.280 1 1 0 1 0 0 0 0 D 0 1.285 1 1 0 1 0 0 0 1 D 1 1.290 1 1 0 1 0 0 1 0 D 2 1.295 1 1 0 1 0 0 1 1 D 3 1.300 1 1 0 1 0 1 0 0 D 4 1.305 1 1 0 1 0 1 0 1 D 5 1.310 Copyright © 2013 Richtek Technology Corporation. All rights reserved. www.richtek.com 8 is a registered trademark of Richtek Technology Corporation. DS8172A-00 November 2013 RT8172A VID7 VID6 VID5 VID4 VID3 VID2 VID1 VID0 H1 H0 DAC Voltage 1 1 0 1 0 1 1 0 D 6 1.315 1 1 0 1 0 1 1 1 D 7 1.320 1 1 0 1 1 0 0 0 D 8 1.325 1 1 0 1 1 0 0 1 D 9 1.330 1 1 0 1 1 0 1 0 D A 1.335 1 1 0 1 1 0 1 1 D B 1.340 1 1 0 1 1 1 0 0 D C 1.345 1 1 0 1 1 1 0 1 D D 1.350 1 1 0 1 1 1 1 0 D E 1.355 1 1 0 1 1 1 1 1 D F 1.360 1 1 1 0 0 0 0 0 E 0 1.365 1 1 1 0 0 0 0 1 E 1 1.370 1 1 1 0 0 0 1 0 E 2 1.375 1 1 1 0 0 0 1 1 E 3 1.380 1 1 1 0 0 1 0 0 E 4 1.385 1 1 1 0 0 1 0 1 E 5 1.390 1 1 1 0 0 1 1 0 E 6 1.395 1 1 1 0 0 1 1 1 E 7 1.400 1 1 1 0 1 0 0 0 E 8 1.405 1 1 1 0 1 0 0 1 E 9 1.410 1 1 1 0 1 0 1 0 E A 1.415 1 1 1 0 1 0 1 1 E B 1.420 1 1 1 0 1 1 0 0 E C 1.425 1 1 1 0 1 1 0 1 E D 1.430 1 1 1 0 1 1 1 0 E E 1.435 1 1 1 0 1 1 1 1 E F 1.440 1 1 1 1 0 0 0 0 F 0 1.445 1 1 1 1 0 0 0 1 F 1 1.450 1 1 1 1 0 0 1 0 F 2 1.455 1 1 1 1 0 0 1 1 F 3 1.460 1 1 1 1 0 1 0 0 F 4 1.465 1 1 1 1 0 1 0 1 F 5 1.470 1 1 1 1 0 1 1 0 F 6 1.475 1 1 1 1 0 1 1 1 F 7 1.480 1 1 1 1 1 0 0 0 F 8 1.485 Copyright © 2013 Richtek Technology Corporation. All rights reserved. DS8172A-00 November 2013 is a registered trademark of Richtek Technology Corporation. www.richtek.com 9 RT8172A VID7 VID6 VID5 VID4 VID3 VID2 VID1 VID0 H1 H0 DAC Voltage 1 1 1 1 1 0 0 1 F 9 1.490 1 1 1 1 1 0 1 0 F A 1.495 1 1 1 1 1 0 1 1 F B 1.500 1 1 1 1 1 1 0 0 F C 1.505 1 1 1 1 1 1 0 1 F D 1.510 1 1 1 1 1 1 1 0 F E 1.515 1 1 1 1 1 1 1 1 F F 1.520 Copyright © 2013 Richtek Technology Corporation. All rights reserved. www.richtek.com 10 is a registered trademark of Richtek Technology Corporation. DS8172A-00 November 2013 RT8172A Functional Pin Description Pin No. Pin Name Pin Function CPU VR Bootstrap Supply for High-Side Gate Driver. This pin powers the high-side MOSFET drivers. Connect this pin to the PHASE1 pin with a bootstrap capacitor. Single-Phase CPU VR On-Time Setting Pin. Connect this pin to VIN with a resistor to set ripple size in PWM mode. 1 BOOT1 2 TONSET 3 ISEN1P Positive Current Sense Input of CPU VR. 4 ISEN1N Negative Current Sense Input of CPU VR. 5 COMP CPU VR Compensation Node. This pin is the output of the error amplifier. 6 FB CPU VR Feedback Voltage Input. This pin is the inverting input node of the error amplifier. 7 RGND Return Ground for CPU VR. This pin is the inverting input node for differential remote voltage sensing. 8 GFXPS2 Set Pin for GPU VR Operation Mode. Logic-high on this pin will force the GPU VR to enter DCM. 9 VCC Controller Power Supply Input. Connect this pin to GND via a ceramic capacitor larger than 1F. 10 SETINI ADC Input for Single-Phase CPU VR VBOOT Voltage Setting. 11 SETINIA ADC Input for Single-Phase GPU VR VBOOT Voltage Setting. 12 TMPMAX ADC Input for Single-Phase CPU VR Maximum Temperature Setting. 13 ICCMAX ADC Input for Single-Phase CPU VR Maximum Current Setting. 14 ICCMAXA ADC Input for Single-Phase GPU VR Maximum Current Setting. 15 TSEN Thermal Monitor Sense Input Pin for CPU VR. 16 OCSET Single-Phase CPU VR Over-Current Protection Threshold Setting. Connect a resistive voltage divider from VCC to ground, and connect the joint of the voltage divider to the OCSET pin. The voltage, VOCSET , at this pin sets the ov er current threshold, ILIMIT, for CPU VR. 17 TSENA Thermal Monitor Sense Input for GPU VR. Single-Phase GPU VR Over-Current Protection Threshold Setting. Connect a resistive voltage divider from VCC to ground, and connect the joint of the v oltage divider to the OCSETA pin. The voltage, VOCSETA, at this pin sets the ov er-current threshold, I LIMIT , for GPU VR. Internal Bias Current Setting. Connect a 53.6k resistor from this pin to GND to set the internal bias current. 18 OCSETA 19 IBIAS 20 VRHOT Thermal Monitor Output (Active-Low). 21 VR_READY CPU VR Voltage Ready Indicator. This pin has an open-drain output. 22 VRA_READY GPU VR Voltage Ready Indicator. This pin has an open-drain output. 23 ALERT Alert Line of SVID Interface (active low). This pin has an open drain output. 24 VDIO Data Transmission Line of SVID Interface. 25 VCLK Clock Signal Line of SVID Interface. 26 RGNDA Return Ground for Single-Phase GPU VR. This pin is the inverting input node for differential remote voltage sensing. Copyright © 2013 Richtek Technology Corporation. All rights reserved. DS8172A-00 November 2013 is a registered trademark of Richtek Technology Corporation. www.richtek.com 11 RT8172A Pin No. Pin Name Pin Function 27 FBA GPU VR Feedback Voltage Input. This pin is the inverting input node of the error amplifier. 28 COMPA Single-Phase GPU VR Compensation Node. This pin is the output of the error amplifier. 29 ISENAN Negative Current Sense Input of Single-Phase GPU VR. 30 ISENAP Positive Current Sense Input of Single-Phase GPU VR. 31 TONSETA Single-Phase GPU VR On-Time Setting. Connect this pin to VIN with a resistor to set ripple size in PWM mode. 32 EN Voltage Regulator Enable Signal Input Pin. 33 BOOTA GPU VR Bootstrap Supply for High-Side Gate Driv er. This pin powers the high-side MOSFET drivers. Connect this pin to the PHASEA pin with a bootstrap capacitor. 34 UGATEA High-Side Gate Driver of GPU VR. This pin drives the high-side MOSFET of GPU VR. 35 PHASEA Switch Node of GPU VR. This pin is the return node of the high-side MOSFET driver for GPU VR. Connect this pin to the joint of the Source of high-side MOSFET, Drain of the low-side MOSFET, and the output inductor. 36 LGATEA Low-Side Gate Driver of GPU VR. This pin drives the low side MOSFET of GPU VR. 37 PVCC MOSFET Driver Power Supply Pin. Connect this pin to GND via a ceramic capacitor larger than 1F. 38 LGATE1 Low-Side Gate Driver of CPU VR. This pin drives the low-side MOSFET of CPU VR. 39 PHASE1 Switch Node of CPU VR. This pin is the return node of the high-side driver for CPU VR. Connect this pin to the joint of the Source of high-side MOSFET, Drain of the low-side MOSFET, and the output inductor. 40 UGATE1 High-Side Gate Driver of CPU VR. This pin drives the high-side MOSFET of CPU VR. GND Ground of Low-Side MOSFET Driver. The exposed pad must be soldered to a large PCB and connected to GND for maximum power dissipation. 41 (Exposed Pad) Copyright © 2013 Richtek Technology Corporation. All rights reserved. www.richtek.com 12 is a registered trademark of Richtek Technology Corporation. DS8172A-00 November 2013 RT8172A VR_READY VRA_READY VRHOT VCC EN ICCMAXA ICCMAX TSEN TSENA SETINI SETINIA TMPMAX ALERT VDIO VCLK Function Block Diagram UVLO MUX From Control Logic ADC SVID XCVR RGNDA Control & Protection Logic DAC Soft-Start & Slew Rate Control VREFA FBA ERROR AMP + - PWM CMP Offset Cancellation GFXPS2 TON Time Generator + - BOOTA COMPA UGATEA Driver Logic Control IBIAS From Control Logic RGND TONSETA LGATEA To Protection Logic DAC OVP/UVP/NVP OCP PHASEA PVCC 10 + ISENAP - ISENAN OCSETA Soft-Start & Slew Rate Control FB VREF ERROR AMP + - PWM CMP Offset Cancellation + TON Time Generator TONSET - COMP BOOT1 UGATE1 To Protection Logic ISEN1P ISEN1N + 10 - OCP OVP/UVP/NVP Driver Logic Control PHASE1 LGATE1 OCSET Copyright © 2013 Richtek Technology Corporation. All rights reserved. DS8172A-00 November 2013 is a registered trademark of Richtek Technology Corporation. www.richtek.com 13 RT8172A Operation The RT8172A adopts the G-NAVPTM (Green Native AVP) which is Richtek's proprietary topology derived from finite DC gain of EA amplifier with current mode control, making it easy to set the droop to meet all Intel CPU requirements of AVP (Adaptive Voltage Positioning). The RT8172A adopts the G-NAVPTM controller, which is one type of current mode constant on-time control with DC offset cancellation. The approach not only can improve DC offset problem for increasing system accuracy but also can have fast transient response for saving BOM. For the RT8172A, when current feedback signal reaches comp signal to generate an on-time width to achieve PWM modulation. Control & Protection Logic  The registers that save the pin setting data from ADC output  The control logic also generate the digital code of the VID that relative to VSET.  Control the on phase of PWM and the on time interval of PWM according to PWMCMP output.  Control the power on sequence.  Control the protection behavior.  Control the operational phase number. Offset Cancellation TON GEN Cancel the current/voltage ripple issue to get the accurate VSEN. Generate the UGATEx pulse according to the phase control signal from the loop control protection logic. UVLO SVID XCVR Interface Detect the VCC voltage and issue POR signal as VCC is high enough.   The interface that receive the SVID signal from CPU and sent the relative signals to Loop Control Protection logic to execute the action by CPU. The SVID logic that control the ADC timing. DAC Generate a analog signal according the digital code generated by Control Logic. Soft-Start & Slew Rate Control Control the Dynamic VID slew rate of VSET according to the SetVID fast or SetVID slow. Copyright © 2013 Richtek Technology Corporation. All rights reserved. www.richtek.com 14 is a registered trademark of Richtek Technology Corporation. DS8172A-00 November 2013 RT8172A Absolute Maximum Ratings               (Note 1) PVCC, VCC to GND ------------------------------------------------------------------------------------RGNDx to GND ------------------------------------------------------------------------------------------TONSETx to GND ---------------------------------------------------------------------------------------Other Pins -------------------------------------------------------------------------------------------------BOOTx to PHASEx -------------------------------------------------------------------------------------PHASEx to GND DC -----------------------------------------------------------------------------------------------------------