Si3460-EVB
Rev. 1.2
19
Not Recom
m
en
ded
for N
ew D
esigns.
Please Co
ns
id
er Si3462 for
N
ew
D
esigns.
9. BOM Component Considerations
See Section
“10. Bill of Materials”.
To achieve optimal performance and full specification compliance, Silicon Labs strongly encourages the use of the
components and vendor part numbers listed in the BOM. If alternate components must be substituted, please note
the following recommendations for components in the power section.
The digital control loop for the dc-dc converter has been optimized for stability with the ~41 µF total output
capacitance and 150 µH shielded inductor (L1). Capacitors C19, C20, C3, and C14 must provide suitably
low ESR for ripple considerations.
Diode D8 must have suitable high voltage and low recovery time. A Schottky diode works well.
Diode D12 must not clamp at 57 V and must clamp to <100 V under worst case surge conditions.
Transistors M1 and M2 are sized for overall efficiency. The larger FQD8P10 can be used in both places, if
desired.
The FET gate driver should be capable of sinking and sourcing approximately 2 A.
Heat dissipating components must be separated from each other and moved away from components that
are heat-sensitive. An example would be moving heat-dissipating inductor L1 so that it is kept away from
electrolytic capacitors C19 and C20.
For better electromagnetic interference (EMI) performance, high current carrying inductors must be of the
shielded type.
Other component considerations:
Resistors R23, R25 and the programming header J6 are used for development purposes only. The Si3460
is not user programmable, and it is not recommended these components be included in actual layouts
(short R23 and R25, and remove J6).
