March 9, 2006
Single-Phase Buck PWM Controller with
Integrated High Speed MOSFET Driver
and Pre-Biased Load Capability
The ISL6540 is a single-phase voltage-mode PWM controller
with input voltage feedforward compensation to maintain a
constant loop gain for optimal transient response, especially for
applications with a wide input voltage range. Its integrated high
speed synchronous rectified MOSFET drivers and other
sophisticated features provide complete control and protection
for a DC/DC converter with minimum external components,
resulting in minimum cost and less engineering design efforts.
The output voltage of the converter can be precisely regulated
with an internal reference voltage of 0.591V, and has a system
tolerance of ±0.85% over commercial temperature and line load
variations. An external voltage can be used in place of the
internal reference for voltage tracking/DDR applications.
The ISL6540 has an internal linear regulator or external linear
regulator drive options for applications with only a single supply
rail. The internal oscillator is adjustable from 250kHz to 2MHz.
The integrated voltage margining, programmable pre-biased
soft-start, differential remote sensing amplifier, and
programmable input voltage POR features enhance the
(28 LD 5x5 QFN)
28 27 26 25 24 23 22
8 9 10 11 12 13 14
• VIN and Power Rail Operation from +3.3V to +20V
• Fast Transient Response - 0 to 100% Duty Cycle
- 15MHz Bandwidth Error Amplifier with 6V/µs Slew Rate
- Voltage-Mode PWM Leading and Trailing-edge
- Input Voltage Feedforward Compensation
• 2.9V to 5.6V High Speed 2A/4A MOSFET Gate Drivers
- Tri-state for Power Stage Shutdown
• Internal Linear Regulator (LR) - 5.6V Bias from VIN
• External LR Drive for Optimal Thermal Performance
• Voltage Margining with Independently Adjustable Upper and
Lower Settings for System Stress Testing & Over Clocking
• Reference Voltage I/O for DDR/Tracking Applications
• Precise 0.591V Internal Reference with Buffered Output
- ±0.85%/±1.25% Over Commercial/Industrial Range
• Source and Sink Overcurrent Protections
- Low- and High-Side MOSFET rDS(ON) Sensing
• Overvoltage and Undervoltage Protections
• Small Converter Size - QFN package
• Oscillator Programmable from 250kHz to 2MHz
• Differential Remote Voltage Sensing with Unity Gain
• Programmable Soft-start with Pre-Biased Load Capability
• Power Good Indication with Programmable Delay
• EN Input with Voltage Monitoring Capability
• Pb-Free Plus Anneal Available (RoHS Compliant)
• Power Supply for some Microprocessors and GPUs
• Wide and Narrow Input Voltage Range Buck Regulators
• Point of Load Applications
• Low-Voltage and High Current Distributed Power Supplies
TEMP. PACKAGE PKG.
MARKING RANGE (°C) (Pb-Free) DWG. #
ISL6540CRZ ISL6540CRZ 0 to 70 28 Ld QFN L28.5x5
ISL6540CRZA ISL6540CRZ 0 to 70 28 Ld QFN L28.5x5
ISL6540IRZ ISL6540IRZ -40 to 85 28 Ld QFN L28.5x5
ISL6540IRZA ISL6540IRZ -40 to 85 28 Ld QFN L28.5x5
*Add “-T” suffix for tape and reel.
NOTE: Intersil Pb-free plus anneal products employ special Pb-free
material sets; molding compounds/die attach materials and 100% matte
tin plate termination finish, which are RoHS compliant and compatible
with both SnPb and Pb-free soldering operations. Intersil Pb-free
products are MSL classified at Pb-free peak reflow temperatures that
meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020.
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774 | Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright Intersil Americas Inc. 2006. All Rights Reserved
All other trademarks mentioned are the property of their respective owners.