MP9928—4V TO 60V SYNCHRONOUS STEP-DOWN CONTROLLER

MP9928 Rev. 1.0

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22

5/20/2016

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3. Route the sensing traces (SENSE+, SENSE-)

in paired way with smallest closed area.

Avoid crossing noisy areas such as SW or

high-side gate drive traces. Place the filter

capacitor for the current sense signal as

close to the IC pins as possible.

4. A short and wide type resistor is recommend

for current sense.

5. VCC1 and VCC2 capacitors should be placed

as close as possible to VCC1 pin and VCC2

pin.

6. Layout the gate drive traces as directly as

possible. Layout the forward and return

traces close together, either running side by

side or on top of each other on adjacent

layers to minimize the inductance of the gate

drive path.

7. The ground return of input/output capacitor

should be tied close with large GND copper

area, and then connect to IC GND pin

through single point.

8. For heavy load, suggest layout large copper,

more layers and more vias for heat sink.

Figure 8 shows the recommended components

place for MP9928 in TSSOP20-EP package.

Figure 9 shows the recommended components

place for MP9928 in QFN20 package. For the

layout, the corresponding schematic can be

found on Figure 10.

R2

R1

R9

R6

C7

C5

C4

C3

C2A

C2B

L2

C11

R14

M1

M2

C8

C1C

C1A

C1B

R6

R15

R20

R19

R12

R11

R7

VIN

GND

VOUT

GND

D1

R13

Bottom Layer

Top Layer

Via

Figure 8: Layout Recommendation

2

C2A

C2B

L1

R6

R15

R20

R19

R12

R11

R1

R2

C3

C4

C5

C6

C7

R8

R9

C1C

D1

C11

R14

VOUT

GND

Bottom Layer

Top Layer

Via

GND

VIN

R7

Figure 9: Layout Recommendation

Design Example

Below

is

a

design

example

following

the

application

guidelines

for

the

following

specifications:

Table 3: Design Example

6V to 60 V

5V

0A-7A

Figure

10

shows

the

detailed

application

schematic, and it is the basis for the typical

performance waveforms. This circuit can work

For more detailed device applications, please

refer to the related Evaluation Board Datasheets