LM2672MX-12 NSC [National Semiconductor], LM2672MX-12 Datasheet - Page 12

• Manufacturer Part Number: LM2672MX-12
• Manufacturer: NSC [National Semiconductor]

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7. Frequency Synchronization (optional)
The LM2672 (oscillator) can be synchronized to run with an
external oscillator, using the sync pin (pin 3). By doing so, the
LM2672 can be operated at higher frequencies than the
standard frequency of 260 kHz. This allows for a reduction in
the size of the inductor and output capacitor.
As shown in the drawing below, a signal applied to a RC filter at
the sync pin causes the device to synchronize to the frequency
of that signal. For a signal with a peak-to-peak amplitude of 3V
or greater, a 1 k
values.
LM2672 Series Buck Regulator Design Procedure (Fixed Output)
PROCEDURE (Fixed Output Voltage Version)
resistor and a 100 pF capacitor are suitable
12
7. Frequency Synchronization (optional)
For all applications, use a 1 k
for the RC filter.
EXAMPLE (Fixed Output Voltage Version)
resistor and a 100 pF capacitor
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