MP2313 – 24V, 1A SYNC STEP DOWN CONVERTER

MP2313 Rev. 1.0

www.MonolithicPower.com

15

9/1/2014

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OUT

OUT

OUT

ESR

IN

S1

VV

ΔV1

R

fL

V

⎛⎞

=× −

×

⎜⎟

×

⎝⎠

The characteristics of the output capacitor also

affect the stability of the regulation system. The

MP2313 can be optimized for a wide range of

capacitance and ESR values.

External Bootstrap Diode

An external bootstrap diode may enhance the

efficiency of the regulator, the applicable

conditions of external BST diode are:

Duty cycle is high: D=

IN

OUT

V

V

>65%

In these cases, an external BST diode is

recommended from the VCC pin to BST pin, as

shown in Figure 8.

MP2313

Figure 8: Add Optional External

Bootstrap Diode to Enhance Efficiency

The recommended external BST diode is

IN4148, and the BST cap is 0.1─1μF.

PCB layout is very important to achieve stable

operation. Please follow these guidelines and

take Figure 9 as reference.

1) Keep the connection of input ground and

GND pin as short and wide as possible.

2) Keep the connection of input capacitor and

IN pin as short and wide as possible.

3) Ensure all feedback connections are short

and direct. Place the feedback resistors and

compensation components as close to the chip

as possible.

4) Route SW away from sensitive analog areas

such as FB.

Notes:

6) The recommended layout is based on the Figure 10 Typical

Application circuit on the page 16.

C1

C6

R1

R2

C5

R4

C4

6

7

8

1

GND

C3

R3

5

3

2

4

R5

C2

L1

C1

C6

R1

R2

C5

R4

C4

6

7

8

1

GND

C3

R3

5

3

2

4

R5

C2

L1

Figure 9: Sample Board Layout