PWM DC/DC Controllers with VID Inputs for Portable GPU Core-Voltage Regulator ISL95874, ISL95875, ISL95876 Features The ISL95874, ISL95875, ISL95876 ICs are Single-Phase Input Voltage Range: 3.3V to 25V Synchronous-Buck PWM regulators featuring Intersils Output Voltage Range: 0.5V to 5V 4 proprietary R Technology. The wide 3.3V to 25V input voltage Precision Regulation range is ideal for systems that run on battery or AC-adapter 4 -Proprietary R Frequency Control Loop power sources. The ISL95875 and ISL95876 are low-cost solutions for applications requiring dynamically selected - 0.5% System Accuracy Over -10C to +100C slew-rate controlled output voltages. The soft-start and dynamic Optimal Transient Response setpoint slew-rates are capacitor programmed. Voltage 4 - Intersils R Modulator Technology identification logic-inputs select four (ISL95875, ISL95876) resistor-programmed setpoint reference voltages that directly set Output Remote Sense the output voltage of the converter between 0.5V and 1.5V, and Extremely Flexible Output Voltage Programmability up to 5V with a feedback voltage divider. - 2-Bit VID Selects Four Independent Setpoint Voltages for 3 4 Compared with R modulator, the R modulator has equivalent ISL95875 and ISL95876 light-load efficiency, faster transient performance, accurately - Simple Resistor Programming of Setpoint Voltages regulated frequency control and all internal compensation. These updates, together with integrated MOSFET drivers and Schottky Selectable 300kHz, 500kHz, 600kHz or 1MHz PWM Frequency bootstrap diode, allow for a high-performance regulator that is in Continuous Conduction highly compact and needs few external components. The Automatic Diode Emulation Mode for Highest Efficiency differential remote sensing for output voltage and selectable Power-Good Monitor for Soft-Start and Fault Detection switching frequency are another two new functions. For maximum efficiency, the converter automatically enters Applications diode-emulation mode (DEM) during light-load conditions, such as system standby. Mobile PC Graphical Processing Unit VCC Rail Mobile PC I/O Controller Hub (ICH) VCC Rail Mobile PC Memory Controller Hub (GMCH) VCC Rail R VCC +5V C VCC C PVCC V IN 3.3V TO 25V CIN Q HS 1 12 GND R BOOT FB1 RTN1 2 11 RTN V UGATE L OUT O 0.5V TO 3.3V 3 10 EN GPIO PHASE Q LS 4 9 CO SREF PGOOD C SEN RTN1 C BOOT R O 0 R FB R OFS FIGURE 1. ISL95874 APPLICATION SCHEMATIC WITH ONE OUTPUT VOLTAGE SETPOINT AND DCR CURRENT SENSE March 2, 2012 CAUTION: These devices are sensitive to electrostatic discharge follow proper IC Handling Procedures. 1 1-888-INTERSIL or 1-888-468-3774 Copyright Intersil Americas Inc. 2011, 2012. All Rights Reserved FN7933.1 Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries. All other trademarks mentioned are the property of their respective owners. R OFS1 C SOFT 5 16 PGND FSEL 15 6 LGATE FB 14 7 PVCC OCSET 13 8 VCC VO R PGOOD R OCSETISL95874, ISL95875, ISL95876 Application Schematics: ISL95874 R VCC +5V C VCC C PVCC V IN 3.3V TO 25V CIN Q GND BOOT HS 112 R FB1 RTN1 RTN UGATE 2 11 V L OUT O 0.5V TO 3.3V EN PHASE GPIO 310 Q SREF PGOOD LS CO 4 9 C SEN RTN1 C BOOT R O R FB 0 R OFS FIGURE 2. ISL95874 APPLICATION SCHEMATIC WITH ONE OUTPUT VOLTAGE SETPOINT AND DCR CURRENT SENSE R VCC +5V C VCC C PVCC V IN 3.3V TO 25V CIN Q GND BOOT HS 112 R FB1 RTN1 RTN UGATE 2 11 V L OUT O R SEN 0.5V TO 3.3V EN PHASE 310 GPIO Q LS SREF PGOOD CO 4 9 C SEN RTN1 C BOOT R O R FB R 0 OFS FIGURE 3. ISL95874 APPLICATION SCHEMATIC WITH ONE OUTPUT VOLTAGE SETPOINT AND RESISTOR CURRENT SENSE FN7933.1 2 March 2, 2012 R OFS1 R OFS1 C C SOFT SOFT FSEL FSEL PGND PGND 5 16 5 16 LGATE LGATE FB FB 6 15 6 15 OCSET PVCC OCSET PVCC 7 14 7 14 VCC VCC VO VO 8 13 8 13 R R PGOOD PGOOD R OCSET R OCSET