AN2544

Circuit operation

13/17

1.9

Performance

Regulation for the VIPer22A-E and VIPer12A-E can be seen below. Keep in mind that the

buck topology will peak charge at zero load. DZ1 will clamp the voltage to 3 - 4 V above the

output. Load regulation is taken from 0.03 A to 0.35 A.

Note:

The following measurements were taken on the appropriate version of the boards.

Discrepancy of measurements can be present, which is to be expected due to the 5%

tolerance of the Zener and equipment used for the measurements. The measurements

shown are at room temperature. If higher operating temperatures are used, current loads

must be adjusted accordingly.

Table 5.

VIPer22ADIP-E, 12 V at 350 mA

VIPer22 buck 12 V / 350 mA

Vin

12 V load

12 V

W in

Efficiency

0

15.81

0.12

0.03

12.58

0.45

0.35

11.7

5.64

72.6%

0.35

12.21

6.12

69.8%

MIN

11.7

MAX

12.58

DELTA

0.88

Line reg.

6.0%

+/- % load reg (.03 to max)

3.8%

Ripple

52

0.12

Short circuit

ok

Table 6.

VIPer12ADIP-E, 12 V at 200 mA

VIPer12 buck 12 V / 200 mA #1

Vin

12 V load

12 V

W in

Efficiency

0

15.6

0.15

0.03

12.7

0.495

0.2

11.85

3.06

77.5%

0.2

12.1

3.25

74.5%

MIN

11.85

MAX

12.7

DELTA

0.85

Line Reg.

2.9%

+/- % load reg (.03 to max)

3.6%