ADP3110A

Dual Bootstrapped, 12 V MOSFET Driver with Output Disable ADP3110A FEATURES All-in-one synchronous buck driver Bootstrapped high-side drive One PWM signal generates both drives Anticross conduction protection circuitry OD for disabling the driver outputs Meets CPU VR requirement when used with Analog Devices Flex-Mode™ 1 controller GENERAL DESCRIPTION The ADP3110A is a dual, high voltage MOSFET driver optimized for driving two N-channel MOSFETs, the two switches in a nonisolated synchronous buck power converter. Each driver is capable of driving a 3000 pF load with a 25 ns propagation delay and a 30 ns transition time. One of the drivers can be bootstrapped and is designed to handle the high voltage slew rate associated with floating high-side gate drivers. The ADP3110A includes overlapping drive protection to prevent shoot-through current in the external MOSFETs. The OD pin shuts off both the high-side and the low-side MOSFETs to prevent rapid output capacitor discharge during system shutdown. The ADP3110A is specified over the commercial temperature range of 0°C to 85°C and is available in an 8-lead SOIC_N or an 8-lead LFCSP_VD package. 1 APPLICATIONS Multiphase desktop CPU supplies Single-supply synchronous buck converters Flex-Mode™ is protected by U.S. Patent 6683441; other patents pending. FUNCTIONAL BLOCK DIAGRAM 12V VCC 4 D1 BST 1 ADP3110A LATCH R1 R2 Q S DELAY CBST2 CBST1 DRVH RG IN 2 8 Q1 TO INDUCTOR RBST SW 7 CMP VCC 6 DRVL 5 CMP 1V CONTROL LOGIC Q2 Figure 1. Rev. 0 Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.461.3113 ©2006 Analog Devices, Inc. All rights reserved. 05832-001 OD 3 DELAY PGND 6 ADP3110A TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 4 ESD Caution.................................................................................. 4 Pin Configuration and Function Descriptions............................. 5 Timing Characteristics..................................................................... 6 Typical Performance Characteristics ............................................. 7 Theory of Operation .........................................................................9 Low-Side Driver ............................................................................9 High-Side Driver ...........................................................................9 Overlap Protection Circuit...........................................................9 Application Information................................................................ 10 Supply Capacitor Selection ....................................................... 10 Bootstrap Circuit........................................................................ 10 MOSFET Selection..................................................................... 10 PC Board Layout Considerations............................................. 11 Outline Dimensions ....................................................................... 13 Ordering Guide .......................................................................... 13 REVISION HISTORY 3/06—Revision 0: Initial Version Rev. 0 | Page 2 of 16 ADP3110A SPECIFICATIONS VCC = 12 V, BST = 4 V to 26 V, TA = 25°C, unless otherwise noted. 1 Table 1. Parameter DIGITAL INPUTS (PWM, OD) Input Voltage High 2 Input Voltage Low2 Input Current2 Hysteresis2 HIGH-SIDE DRIVER Output Resistance, Sourcing Current Output Resistance, Sinking Current Output Resistance, Unbiased Transition Times Propagation Delay Times Symbol Conditions Min 2.0 −1 90 BST to SW = 12 V BST to SW = 12 V BST to SW = 0 V BST to SW = 12 V, CLOAD = 3 nF, see Figure 4 BST to SW = 12 V, CLOAD = 3 nF, see Figure 4 BST to SW = 12 V, CLOAD = 3 nF, see Figure 4 BST to SW = 12 V, CLOAD = 3 nF, see Figure 4 See Figure 3 See Figure 3 SW to PGND 0.8 +1 250 2.6 1.4 10 40 30 45 25 20 40 10 2.5 1.4 10 40 20 15 30 20 110 110 95 4.15 BST = 12 V, IN = 0 V VCC rising 2 1.5 350 190 190 150 13.2 5 3.0 3.4 1.8 50 30 35 40 35 3.4 1.8 55 45 65 35 35 55 Typ Max Unit V V μA mV Ω Ω kΩ ns ns ns ns ns ns kΩ Ω Ω kΩ ns ns ns ns ns ns ns ns V mA V mV trDRVH tfDRVH tpdhDRVH tpdlDRVH t pdl OD tpdh OD SW Pull-Down Resistance LOW-SIDE DRIVER Output Resistance, Sourcing Current Output Resistance, Sinking Current Output Resistance, Unbiased Transition Times Propagation Delay Times trDRVL tfDRVL tpdhDRVL tpdlDRVL t pdl OD OD VCC = PGND CLOAD = 3 nF, see Figure 4 CLOAD = 3 nF, see Figure 4 CLOAD = 3 nF, see Figure 4 CLOAD = 3 nF, see Figure 4 See Figure 3 See Figure 3 SW = 5 V SW = PGND tpdh Timeout Delay SUPPLY Supply Voltage Range2 Supply Current2 UVLO Voltage2 Hysteresis2 1 2 VCC ISYS All limits at temperature extremes are guaranteed via correlation using standard statistical quality control (SQC) methods. Specifications apply over the full operating temperature range TA = 0°C to 85°C. Rev. 0 | Page 3 of 16 ADP3110A ABSOLUTE MAXIMUM RATINGS Table 2. Parameter VCC BST DC