iru3055 International Rectifier Corp., iru3055 Datasheet - Page 16

• Manufacturer Part Number: iru3055
• Description: 5-bit Programmable 3-phase Synchronous Buck Controller Ic -
• Manufacturer: International Rectifier Corp.

IRU3055
Component Connection
• No data bus should be passing through the switching
regulator especially close to the fast transition nodes
such as PWM drivers or the inductor voltage.
•
to ground, another layer as power layer for the constant
power input and output such as 5V, 12V, and 1.5V out-
put. Connect all grounds to the ground plane using di-
rect vias to the ground plane.
•
plane to connect the high current path connections ei-
ther using component side or the solder side. These
connections include:
Connect the rest of the components using the shortest
trace possible.
16
If possible, using four layer board, dedicate one layer
Use large and low impedance/low inductance PCB
(a) Input capacitor to the drain of high side MOSFET
Q1, Q3 and Q5.
(b) The interconnection between source of high side
MOSFET such as Q1 and low side MOSFET such
as Q2.
(c) From drain of low side MOSFET to output Induc-
tor .
(d) From output inductor to output capacitor. Make
sure the impedance from output inductor to output
voltage slot (also the voltage feedback sensing point)
are as identical or symmetrical as possible.
(e) From each output capacitor to output slot.
(f) From input inductor to input capacitor.
www.irf.com
08/13/02
Rev. 1.4