ISL6228: High-Performance Dual-Output Buck Controller for Notebook Applications

The ISL6228 IC is a dual channel synchronous-buck PWM controller featuring Intersil's Robust Ripple Regulator (R3) technology that delivers truly superior dynamic response to input voltage and output load transients. Integrated MOSFET drivers and bootstrap diodes result in fewer components and smaller implementation area.

Intersil's R3 technology combines the best features of fixedfrequency and hysteretic PWMs while eliminating many of their shortcomings. R3 technology employs an innovative modulator that synthesizes an AC ripple voltage signal VR, analogous to the output inductor ripple current. The AC signal VR enters a window comparator where the lower threshold is the error amplifier output VCOMP, and the upper threshold is a programmable voltage reference VW, resulting in generation of the PWM signal. The voltage reference VW sets the steady-state PWM frequency. Both edges of the PWM can be modulated in response to input voltage transients and output load transients, much faster than conventional fixedfrequency PWM controllers. Unlike a conventional hysteretic converter, each channel of the ISL6228 has an error amplifier that provides ±1% voltage regulation at the FB pin.

The ISL6228 has a 1.5ms digital soft-start and can be started into a pre-biased output voltage. A resistor divider is used to program the output voltage setpoint. The ISL6228 operates in continuous-conduction-mode (CCM) in heavy load, and in diode-emulation-mode (DEM) in light load to improve light-load efficiency. In CCM, the controller always operates as a synchronous rectifier. In DEM, the low-side MOSFET is permitted to stay off, blocking negative current flow into the low-side MOSFET from the output inductor.

Key Features
  • High performance R3 technology
  • Fast transient response
  • ±1% regulation accuracy: -10°C to +100°C
  • Individual power stage input rail for each channel
  • Wide input voltage range: +3.3V to +25V
  • Output voltage range: +0.6V to +5V
  • Diode emulation mode for increased light load efficiency
  • Programmable PWM frequency: 200kHz to 600kHz
  • Pre-biased output start-up capability
  • Integrated MOSFET drivers and bootstrap diode
  • Internal digital soft-start
  • Power good monitor
  • Fault protection
    • Undervoltage protection
    • Soft crowbar overvoltage protection
    • Inductor DCR overcurrent protection
    • Over-temperature protection
    • Fault identification by PGOOD pull-down resistance
  • Pb-free available (RoHS compliant)
Applications
  • General purpose switching buck regulators
  • PCI express graphical processing unit
  • Auxiliary power rail
  • VRM
  • Network adapter
Typical Diagram
Application Notes
TitleTypeUpdatedSizeOther Languages
AN1652: iSim:PE Users GuidePDF13 Nov 20141.45 MB
Datasheets
TitleTypeUpdatedSizeOther Languages
ISL6228 DatasheetPDF17 Nov 2014462 KB简体中文
User Guides
TitleTypeUpdatedSizeOther Languages
ISL6228HIEVAL3Z User GuidePDF11 Dec 2014906 KB
ISL6228LOEVAL3Z User GuidePDF04 Dec 2014904 KB
ISL8200MEVAL2PHZ User GuidePDF13 Nov 2014680 KB
ISL6228EVAL3Z User GuidePDF13 Nov 2014895 KB
White Papers
TitleTypeUpdatedSizeOther Languages
Five Easy Steps to Create a Multi-Load Power SolutionPDF30 Jan 2017502 KB
Order Information
Part NumberPackage TypeWeight(g)PinsMSL RatingPeak Temp (°C)RoHS Status
ISL6228HRTZ28 Ld TQFN0.037283260RoHS
ISL6228HRTZ-T28 Ld TQFN T+R0.037283260RoHS
ISL6228IRTZ28 Ld TQFN0.037283260RoHS
ISL6228IRTZ-T28 Ld TQFN T+R0.037283260RoHS
ISL6228EVAL3ZN/ARoHS
ISL6228HIEVAL3ZN/ARoHS
ISL6228LOEVAL3ZN/ARoHS
ISL6228 Datasheet 17 Nov 2014
ISL6228 Datasheet 17 Nov 2014
28 Ld TQFN T+R ISL6228
ISL6228
AN1652: iSim:PE Users Guide 13 Nov 2014
ISL6228HIEVAL3Z User Guide 11 Dec 2014
ISL6228LOEVAL3Z User Guide 04 Dec 2014
ISL8200MEVAL2PHZ User Guide 13 Nov 2014
ISL6228EVAL3Z User Guide 13 Nov 2014
Five Easy Steps to Create a Multi-Load Power Solution 30 Jan 2017