Texas Instruments SLVU013, Руководство пользователя

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2-1 Design Procedure
Design Procedure
The SLVP111–114 are dc-dc synchronous buck converter evaluation modules
(EVMs) that provide a regulated output voltage at up to 6 A with a power input
voltage range of 4.5 V to 6 V. A low power 12-V, 20-mA source is also required
to power the TPS56xx controller. The controller operates
at a nominal
frequency of 135 kHz for 5 V input and 3.3 V output. To provide the highest level
of performance, the EVM converters use
hysteretic, or ripple, control.
Hysteretic-controlled synchronous buck converters have several advantages
over conventional PWM-controlled power supplies:
Correction of output voltage variations caused by output-load or input-
voltage transients is extremely fast.
The user controls output ripple by adjusting the operational parameters of
the converter, instead of relying on brute force methods requiring the
choice of an output filter.
Hysteretic control sets the operational frequency of the converter. For a
given set of external components, the lower the permissible ripple setting,
the higher the operational frequency.
There is no control loop to design.
Topic Page
2.1 TPS56xx Functions 2–2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 External Component Selection 2–14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chapter 2