Feb21-07

SP7662 Evaluation Manual

©2007 Sipex Corporation

Page 3 of 11

Adjusting the Current downward is controlled by adjusting R8.













⋅

⋅

+

⋅

=

DCR)

(Imax

-

60mV

DCR)

(Imax

60mV)

-

(Vout

R4

R8

Equation 3

Where

DCR is the Inductor winding resistance

Further details on the current limit can be found in the SP7662 data sheet.

For the Inter-Technical Inductor on this demo board DCR= 4.1m

Ω nominal.

POWER SUPPLY DATA

The SP7662ER is designed with an very accurate 2.0% reference over line, load and

temperature. Figure 1 data shows a typical SP7662 evaluation board efficiency plot, with

efficiencies up to 93% and output currents up to 12A. The output voltage ripple of less than

30mV at full load and the LX node are shown in figure 2. Figures 3 and 4 illustrate a 6A-to-12A

and 0A-to-12A Load Step. Short circuit and current limit are shown in Figures 5 and 6. Typical

startup characteristics into a full load and no load are shown in figures 7 and 8. All data was

While data on individual power supply boards may vary, the capability of the SP7662ER

of achieving high accuracy over a range of load conditions shown here is quite impressive and

desirable for accurate power supply design.

7662 Efficiency

12Vin - 3.3Vout - 12Amps

76.00

78.00

80.00

82.00

84.00

86.00

88.00

90.00

92.00

94.00

96.00

02

46

8

10

12

Iout (Amps)

Figure 1. Efficiency vs Load