The ISL6420B simplifies the implementation of a complete control and protection scheme for a high-performance DC/DC buck converter. It is designed to drive N-Channel MOSFETs in a synchronous rectified buck topology. The ISL6420B integrates control, output adjustment, monitoring and protection functions into a single package. Additionally, the IC features an external reference voltage tracking mode for externally referenced buck converter applications and DDR termination supplies, as well as a voltage margining mode for system testing in networking DC/DC converter applications. The ISL6420B provides simple, single feedback loop, voltage mode control with fast transient response. The output voltage of the converter can be precisely regulated to as low as 0. 6V. The operating frequency is fully adjustable from 100kHz to 1. 4MHz. High frequency operation offers cost and space savings. The error amplifier features a 15MHz gain-bandwidth product and 6V/µs slew rate that enables high converter bandwidth for fast transient response. The PWM duty cycle ranges from 0% to 100% in transient conditions. Selecting the capacitor value from the ENSS pin to ground sets a fully adjustable PWM soft-start. Pulling the ENSS pin LOW disables the controller. The ISL6420B monitors the output voltage and generates a PGOOD (power good) signal when soft-start sequence is complete and the output is within regulation. A built-in overvoltage protection circuit prevents the output voltage from going above typically 115% of the set point. Protection from overcurrent conditions is provided by monitoring the rDS(ON) of the upper MOSFET to inhibit the PWM operation appropriately. This approach simplifies the implementation and improves efficiency by eliminating the need for a current sensing resistor.

Features

  • Operates From:
  • 4.5V to 5.5V Input
  • 5.5V to 28V Input
  • 0.6V Internal Reference Voltage
  • ±2.0% Reference Accuracy
  • Resistor-Selectable Switching Frequency
  • 100kHz to 1.4MHz
  • Voltage Margining and External Reference Tracking Modes
  • Output can Sink or Source Current
  • Lossless, Programmable Overcurrent Protection
  • Uses Upper MOSFET's rDS(ON)
  • Programmable Soft-Start
  • Drives N-Channel MOSFETs
  • Simple Single-Loop Control Design
  • Voltage-Mode PWM Control
  • Fast Transient Response
  • High-Bandwidth Error Amplifier
  • Full 0% to 100% Duty Cycle
  • Extensive Circuit Protection Functions
  • PGOOD, Overvoltage, Overcurrent, Shutdown
  • Diode Emulation during Startup for Pre-Biased Load Applications
  • Offered in 20 Ld QFN and QSOP Packages
  • QFN (4x4) Package
  • QFN compliant to JEDEC PUB95 MO-220 QFN -Quad Flat No Leads - Product Outline
  • QFN Near Chip Scale Package Footprint; Improves PCB Efficiency, Thinner in Profile
  • Pb-Free (RoHS Compliant)

Applications

  • Power Supplies for Microprocessors/ASICs Embedded Controllers DSP and Core Processors DDR SDRAM Bus Termination
  • Ethernet Routers and Switchers
  • High-Power DC/DC Regulators
  • Distributed DC/DC Power Architecture
  • Personal Computer Peripherals
  • Externally Referenced Buck Converters

Product Options

Part Number Part Status Pkg. Type Carrier Type MOQ Buy Sample
Active QSOP Tube 580
Availability
Active QSOP Reel 250
Availability
Active QSOP Reel 1000
Availability
Active QFN Tube 75
Availability
Active QFN Reel 250
Availability
Active QFN Reel 1000
Availability

Documentation & Downloads

Title Other Languages Type Format File Size Date
Datasheets & Errata
ISL6420B Datasheet Datasheet PDF 1.06 MB
User Guides & Manuals
ISL6420BEVAL7Z User Guide Manual PDF 866 KB
ISL6420BEVAL6Z User Guide Manual PDF 868 KB
ISL6420BEVAL1Z User Guide Manual PDF 1.09 MB
Application Notes & White Papers
Five Easy Steps to Create a Multi-Load Power Solution White Paper PDF 846 KB
AN1681: Grounding Techniques Application Note PDF 509 KB
AN1684: Nonideality of Ground Application Note PDF 397 KB
PCNs & PDNs
PCN15046 - Wafer Fabrication Site Change for Listed Intersil Products - Global Foundry P6 Process transfer to Palm Bay - Phase II Product Change Notice PDF 398 KB
PCN13060 - Test Site Change for the Listed Intersil Products Product Change Notice PDF 223 KB
PCN13037 - Alternate Bond Wire Material for Assembly of the Listed Intersil QSOP Packaged Product Product Change Notice PDF 268 KB
PCN13025 - Alternate Bond Wire Material and Manufacturing Facilities for Assembly of the Listed Intersil DFN/QFN Packaged Products - Advanced Semiconductor Engineering (ASECL) - Chung-Li , Taiwan and STATS ChipPAC (SCM) - Kuala Lumpur, Mal Product Change Notice PDF 106 KB
PCN13009 - Alternate Bond Wire Material and Manufacturing Facilities for Assembly of the Listed Intersil DFN/QFN Packaged Products - Advanced Semiconductor Engineering (ASECL) - Chung-Li (ASECL), Taiwan and STATS ChipPAC (SCM) - Kuala Lump Product Change Notice PDF 173 KB

Boards & Kits

Part Number Title Type Company
ISL6420BEVAL1Z Advanced Single Synchronous Buck PWM Controller Evaluation Board Evaluation Renesas
ISL6420BEVAL2Z Advanced Single Synchronous Buck PWM Controller Evaluation Board Evaluation Renesas