MULTIPHSPOL-RD Silicon Laboratories Inc, MULTIPHSPOL-RD Datasheet - Page 21

• Manufacturer Part Number: MULTIPHSPOL-RD
• Description: KIT REFERENCE DESIGN FOR SI825X
• Manufacturer: Silicon Laboratories Inc
• Type: Other Power Managementr

Specifications of MULTIPHSPOL-RD

• Main Purpose: DC/DC, Step Down
• Outputs And Type: 1, Non-Isolated
• Voltage - Output: 3.3V
• Current - Output: 40A
• Voltage - Input: 10 ~ 15V
• Regulator Topology: Buck
• Frequency - Switching: 391kHz
• Board Type: Fully Populated
• Utilized Ic / Part: SI8250, SI8251, SI8252
• Input Voltage: 10 V to 15 V
• Output Voltage: 3.3 V
• Interface Type: USB
• Product: Power Management Modules
• Supply Current: 10 A
• For Use With/related Products: Si8250
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Power - Output: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1323

6. Layout Considerations
The mixed-signal nature of the Si8250/1/2 mandates
clean bias supplies and ground returns. It is best to
provide separate ground planes for analog, digital, and
power switch returns. These planes should tie together
at only one point to eliminate the possibility of circulating
ground currents. For best performance, the V
should be decoupled from the main supply. The LQFP-
32 package provides the best noise performance
because it has separate analog and digital V
ground inputs (V
lengths as short
10 uF
as possible
Keep trace
DDA
lengths as short
10 uF
as possible
Keep trace
, GNDA).
GNDA
0.1 uF
Figure 10. Power Supply Connections for LQFP-32 Package
Figure 11. Power Supply Connections for QFN-28 Package
0.1 uF
GNDA
V
500 mA, 40 Ω
Si8250/1/2
Ferrite bead
DDA
DD
DD
supply
GND
VDD
V
GND
500 mA, 40 Ω
and
Ferrite bead
DD
Rev. 1.0
Si8250/1/2
As shown in Figure 10, the V
consisting of a 1 Ω resistor in series with a 500 mA,
40 Ω ferrite bead and a parallel combination of a 10 µF
with a 0.1 µF high-frequency bypass capacitor. All
connections should be kept as short as possible. V
and GNDA should be connected into their respective
ground planes. The QFN-28 package shares analog
and digital power with ground on the same pins. Power
supply decoupling is shown in Figure 11. Again, all
connections should be kept as short as possible.
10 uF
1 Ω
0.1 uF
1 Ω
DDA
Si8250/1/2
2.5 V
is decoupled by a filter
2.5 V
DDA
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