IR3651SPBF International Rectifier, IR3651SPBF Datasheet - Page 18

• Manufacturer Part Number: IR3651SPBF
• Description: IC CTLR SYNC PWM BUCK 14-SOIC
• Manufacturer: International Rectifier

Specifications of IR3651SPBF

• Pwm Type: Voltage Mode
• Number Of Outputs: 1
• Frequency - Max: 460kHz
• Duty Cycle: 80%
• Voltage - Supply: 4.5 V ~ 13.2 V
• Buck: Yes
• Boost: No
• Flyback: No
• Inverting: No
• Doubler: No
• Divider: No
• Cuk: No
• Isolated: No
• Operating Temperature: 0°C ~ 125°C
• Package / Case: 14-SOIC (3.9mm Width), 14-SOL
• Frequency-max: 460kHz
• Package: 14-Pin SOIC (NB)
• Circuit: Sync PWM Controller
• Vcc (min): 4.5
• Vcc (max): 13.2
• Iout (a): 25
• Switch Freq (khz): programmable to 400kHz
• Pbf: PbF Option Available
• For Use With: IRDC3651 - KIT REF DESIGN SYNCH BUCK REG
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

12/07/2010
Layout Consideration
The layout is very important when designing high
frequency switching converters. Layout will affect
noise pickup and can cause a good design to
perform with less than expected results.
Start to place the power components, make all
the connection in the top layer with wide, copper
filled areas.
The inductor, output capacitor and the MOSFET
should be close to each other as possible. This
helps to reduce the EMI radiated by the power
traces due to the high switching currents through
them. Place input capacitor directly to the drain of
the high-side MOSFET, to reduce the ESR
replace the single input capacitor with two
parallel units
Part Marking Information
.
The feedback part of the system should be kept
away from the inductor and other noise sources.
The
capacitors for Vcc, DRVc and Vb should be close
to respective pins. It is important to place the
feedback
resistors and compensation components close to
Fb and Comp pins.
In multilayer PCB use one layer as power ground
plane and have a control circuit ground (analog
ground), to which all signals are referenced. The
goal is to localize the high current path to a
separate loop that does not interfere with the
more sensitive analog control function. These two
grounds must be connected together on the PC
board layout at a single point.
critical
components
bypass
components
including
IR3651SPBF
such
feedback
as
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