MP2207 – 16V, 4A, 1.3MHz SYNCHRONOUS STEP-DOWN CONVERTER

MP2207 Rev. 0.92

www.MonolithicPower.com

10

9/1/2010

MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.

Preliminary Specifications Subject to Change

© 2010 MPS. All Rights Reserved.

Output Capacitor Selection

The output capacitor keeps output voltage ripple

small and ensures regulation loop stable. The

output capacitor impedance shall be low at the

switching frequency. Ceramic capacitors with

X5R or X7R dielectrics are recommended. If

electrolytic capacitor is used, pay attention to

output ripple voltage, extra heating, and the

selection of feedback resistor R1 (refer to “Output

Voltage Setting” section) due to large ESR of

approximately:

OUT

IN

OUT

OUT

IN

OSC

OSC

Vx(V

V

)

1

V

x(ESR

)

V xf

xL

8xf

xC3

−

Δ≤

+

External Schottky Diode

For this part, an external schottky diode is

recommended to be placed close to "SW" and

"GND" pins, especially when the output current is

larger than 2A.

With the external schottky diode, the voltage

spike and negative kick on "SW" pin can be

minimized; moreover, the conversion efficiency

can also be improved a little.

For the external schottky diode selection, it's

noteworthy that the maximum reverse voltage

rating of the external diode should be larger than

the maximum input voltage. As for the current

rating of this diode, 0.5A rating should be

sufficient.