January 17, 2006
Synchronous Buck Pulse-Width
Modulator (PWM) Controller
The ISL6535 is a high performance synchronous controller
for demanding DC/DC converter applications. It provides
overcurrent fault protection and is designed to safely startup
into prebiased output loads.
The output voltage of the converter can be precisely
regulated to as low as 0.597V, with a maximum tolerance of
±1% over the commercial temperature range, and ±1.5%
over the industrial temperature range.
The ISL6535 provides simple, single feedback loop, voltage-
mode control with fast transient response. It includes a
triangle-wave oscillator that is adjustable from below 50kHz
to over 1.5MHz. Full (0% to 100%) PWM duty cycle support
The error amplifier features a 15MHz gain-bandwidth
product and 6V/µs slew rate which enables high converter
bandwidth for fast transient performance.
The ISL6535's overcurrent protection monitors the current
by using the rDS(ON) of the upper MOSFET which eliminates
the need for a current sensing resistor.
(14 LD NARROW SOIC AND 16 LD QFN)
16 15 14 13
• Operates from +12V Input
• Excellent Output Voltage Regulation
- 0.597V Internal Reference
- ±1% Over the Commercial Temperature Range
- ±1.5% Over the Industrial Temperature Range
• Simple Single-Loop Control Design
- Voltage-Mode PWM Control
• Fast Transient Response
- High-Bandwidth Error Amplifier
- Full 0% to 100% Duty Ratio
- Leading and Falling Edge Modulation
• Small Converter Size
- Constant Frequency Operation
- Oscillator Programmable from 50kHz to Over 1.5MHz
• 12V High Speed MOSFET Gate Drivers
- 2.0A Source/3A Sink at 12V Low Side Gate Drive
- 1.25A Source/2A Sink at 12V High Side Gate Drive
- Drives Two N-Channel MOSFETs
• Overcurrent Fault Monitor
- High-Side MOSFET’s rDS(ON) Sensing
- Reduced ~120ns Blanking Time
• Converter can Source and Sink Current
• Soft-Start Done and an External Reference Pin for
Tracking Applications are Available in the QFN Package
• Pin Compatible with ISL6522
• Supports Start-Up into Prebiased Loads
• Pb-Free Plus Anneal Available (RoHS Compliant)
• Power Supply for some Pentium®, PowerPC™, as well as
• High-Power 12V Input DC/DC Regulators
• Low-Voltage Distributed Power Supplies
ISL6535CBZ 6535CBZ 0 to 70 14 Ld SOIC M14.15
ISL6535IBZ 6535IBZ -40 to 85 14 Ld SOIC M14.15
ISL6535CRZ 6535CRZ 0 to 70 16 Ld 4x4 QFN L16.4x4
ISL6535IRZ 6535IRZ -40 to 85 16 Ld 4x4 QFN L16.4x4
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.
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Copyright Intersil Americas Inc. 2006. All Rights Reserved
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