SC403MLTRT Semtech, SC403MLTRT Datasheet - Page 27

• Manufacturer Part Number: SC403MLTRT
• Manufacturer: Semtech

Specifications of SC403MLTRT

• Lead Free Status / Rohs Status: Supplier Unconfirmed

SC403
Applications Information (continued)
that frequency tends to falls slightly with increasing input
voltage.
The switching frequency also varies with load current as a
result of the power losses in the MOSFETs and the induc-
tor. For a conventional PWM constant-frequency con-
verter, as load increases the duty cycle also increases
slightly to compensate for IR and switching losses in the
MOSFETs and inductor. A constant on-time converter
must also compensate for the same losses by increasing
the effective duty cycle (more time is spent drawing
energy from V
as losses increase). The on-time is essen-
IN
tially constant for a given V
/V
combination, to offset
OUT
IN
the losses the off-time will tend to reduce slightly as load
increases. The net effect is that switching frequency
increases slightly with increasing load.
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