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7

LS-SERIES

(28V Input, Single/Dual Output)

LS Series Output Voltage Adjustment

Output of LS series can be adjusted to be greater or less than the nominal output voltage with an external

resistor. However, the ranges of the output voltages are limited depending on the model as specified in

Table 1 and 2. An approximate value of the resistor can be determined using the following formula.

For Single Output Model:

Radj = A - (B x Vout)

(C x Vout) - D

For Dual Output Model:

Radj =

A - (B x 2Vout)

(C x 2Vout) - D

Where:

Radj is the value of the external resistor in kilo-ohms, Rdown or Rup in Figure 1 or 2.

Power rating of the resistor shall be

≥ 0.125W. Metal film resistor with temperature coefficient

of

≤ ±50 ppm and tolerance of ≤ 1% is recommended. However, the final selection is dependent

on specific design requirements.

Vout is the desired output voltage in volts.

A, B, C, and D are unique constants depending on the model as shown in Table 1

for single output models and Table 2 for dual output models.

Table 1: Single Output Voltage Ranges and Constants

Model

Output Voltage Range

(V) (1)

AB

C

D

1.500 to 1.600

69.65

32.39

8.75

13.13

1.400 to 1.500

56.85

40.47

7.14

10.72

2.500 to 2.750

48.42

13.04

3.52

8.81

2.250 to 2.500

39.52

21.19

2.88

7.19

3.300 to 3.630

43.48

9.25

2.50

8.25

2.970 to 3.300

35.48

16.18

2.04

6.73

5.000 to 5.500

119.48

20.00

2.27

11.36

4.500 to 5.000

97.52

29.31

1.85

9.27

12.000 to 13.200

295.22

19.98

2.27

27.24

10.800 to 12.000

241.01

53.31

1.85

22.24

15.000 to 16.500

370.61

19.98

2.27

34.05

13.500 to 15.000

302.55

63.61

1.85

27.80

LS2805S

LS2812S

LS2815S

LS2801R5S

LS2802R5S

LS2803R3S