9

Layout Considerations

As in all switching power supplies, the layout is an important

step in the design process, more so at high peak currents

and switching frequencies. Improper layout practice will give

rise to Stability and EMI issues. It is recommended that wide

and short traces are used for the main current paths. The

input capacitor should be placed as close as possible to the

IC pins. This applies to the output inductor and capacitor as

well. The analog ground, GND, and the power ground,

PGND, need to be separated. Use a common ground node

to minimize the effects of ground noise.

Performance Curves and Waveforms

FIGURE 4. ISL6410 EFFICIENCY vs LOAD CURRENT

FIGURE 5. ISL6410 VIN vs EFFICIENCY

FIGURE 6. ISL6410A EFFICIENCY vs LOAD CURRENT

FIGURE 7. ISL6410A EFFICIENCY vs VIN

1000

100

50

100

80

50

IOUT LOAD CURRENT (mA)

90

70

60

VOUT = 1.8V

VOUT = 1.2V

VOUT = 1.5V

3.3

2.9

90

80

70

60

VIN INPUT VOLTAGE (V)

3.1

3.5

50

IOUT = 200mA

IOUT = 600mA

100

1000

100

50

100

80

50

IOUT LOAD CURRENT (mA)

90

70

60

VOUT = 3.3V

VOUT = 1.2V

VOUT = 1.8V

5.6

5.0

4.4

VIN (V)

4.8

5.2

4.6

5.4

90

80

70

60

50

100

IOUT = 600mA

IOUT = 200mA

ISL6410, ISL6410A