Application Notes

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Adjusting the Output Voltage of the PTH03050W &

PTH05050W Wide-Output Adjust Power Modules

value higher than 0.8 V. The adjustment range of the

the PTH05050W (5-V input) from 0.8 V to 3.6 V. The

adjustment method requires the addition of a single

the preferred value of the external resistor for a number

of standard voltages, along with the actual output volt-

age that this resistance value provides.

For other output voltages the value of the required resistor

can either be calculated using the following formula, or

simply selected from the range of values given in Table 2-2.

Figure 2-1 shows the placement of the required resistor.

= 10 k

Ω ·

0.8 V

– 2.49 k

Ω

Notes:

1. Modules that operate from a 3.3-V input bus should

not be adjusted higher than 2.5 V.

2. A 0.05-W resistor may be used. The tolerance should

be 1%, with temperature stability of 100 ppm/°C (or

better). Place the resistor as close to the regulator as

possible. Connect the resistor directly between pins 5

and 1 using dedicated PCB traces.

the stability of the regulator.

0.800

Open

0.825

318 k

Ω

0.850

158 k

Ω

0.875

104 k

Ω

0.900

77.5 k

Ω

0.925

61.5 k

Ω

0.950

50.8 k

Ω

0.975

43.2 k

Ω

1.000

37.5 k

Ω

1.025

33.1 k

Ω

1.050

29.5 k

Ω

1.075

26.6 k

Ω

1.100

24.2 k

Ω

1.125

22.1 k

Ω

1.150

20.4 k

Ω

1.175

18.8 k

Ω

1.200

17.5 k

Ω

1.225

16.3 k

Ω

1.250

15.3 k

Ω

1.275

14.4 k

Ω

1.300

13.5 k

Ω

1.325

12.7 k

Ω

1.350

12.1 k

Ω

1.375

11.4 k

Ω

1.400

10.8 k

Ω

1.425

10.3 k

Ω

1.450

9.82 k

Ω

1.475

9.36 k

Ω

1.50

8.94 k

Ω

1.55

8.18 k

Ω

1.60

7.51 k

Ω

1.65

6.92 k

Ω

1.70

6.4 k

Ω

1.75

5.93 k

Ω

1.80

5.51 k

Ω

1.85

5.13 k

Ω

1.90

4.78 k

Ω

1.95

4.47 k

Ω

698

Ω

3.309V

2.5 V

2.21 k

Ω

2.502 V

2 V

4.12 k

Ω

2.010 V

1.8 V

5.49 k

Ω

1.803 V

1.5 V

8.87 k

Ω

1.504 V

1.2 V

17.4 k

Ω

1.202 V

1 V

36.5 k

Ω

1.005 V

0.8 V

Open

0.8 V

PTH03050W & PTH05050W

Table 2-2; Output Voltage Set-Point Resistor Values

2.00

4.18 k

Ω

2.05

3.91 k

Ω

2.10

3.66 k

Ω

2.15

3.44 k

Ω

2.20

3.22 k

Ω

2.25

3.03 k

Ω

2.30

2.84 k

Ω

2.35

2.67 k

Ω

2.40

2.51 k

Ω

2.45

2.36 k

Ω

2.50

2.22 k

Ω

2.55

2.08 k

Ω

2.60

1.95 k

Ω

2.65

1.83 k

Ω

2.70

1.72 k

Ω

2.75

1.61 k

Ω

2.80

1.51 k

Ω

2.85

1.41 k

Ω

2.90

1.32 k

Ω

2.95

1.23 k

Ω

3.00

1.15 k

Ω

3.05

1.07 k

Ω

3.10

988

Ω

3.15

914

Ω

3.20

843

Ω

3.25

775

Ω

3.30

710

Ω

3.35

647

Ω

3.40

587

Ω

3.45

529

Ω

3.50

473

Ω

3.55

419

Ω

3.60

367

Ω

V

IN

C

IN

100 µF

(Required)

C

OUT

100 µF

(Optional)

GND

V

OUT

R

SET

1 %

0.1 W

PTH03050W

15

6

3

4

2

Track

V

IN

V

O

GND

Inhibit