Application Notes

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PT6650 Series

Adjusting the Output Voltage of the

PT6650 5-A 24-V Bus Converter Series

The output voltage of the PT6650 Series ISRs may be

adjusted higher or lower than the factory trimmed pre-

set voltage with the addition of a single external resistor.

Table 3-1 gives the allowable adjustment range for each

Adjust Up:

An increase in the output voltage is obtained

7-10 (GND).

Adjust Down:

To decrease the output voltage, add a resis-

Refer to Figure 3-1 and Table 3-2 for both the placement and

Notes:

location. Place the resistor as close to the ISR as possible.

3. If the remote sense feature is being used, connecting the

Sense) can benefit load regulation.

4. Adjustments to the output voltage may place additional

limits on the input voltage for the part. The revised limits

must comply with the following requirements.

5. For output voltages above 12.5 Vdc, the maximum output

current must be limited to 4 Adc.

also be calculated using the following formulae.

=

=

Figure 3-1

Table 3-1

PT6650 ADJUSTMENT AND FORMULA PARAMETERS

Series Pt #

PT6652

PT6651

PT6653

PT6654

PT6656

PT6655

2.5 V

3.3 V

5 V

9 V

12 V

15 V

1.8 V

2.2 V

3 V

6 V

9 V

10 V

4.3 V

4.7 V

6.5 V

10.2 V

13.6 V

17 V

Ω

Ω

Ω

Ω

Ω)

4.99

4.22

2.49

2

2

2

Ω

Ω

Ω

Ω

Ω)

2.49

4.99

4.99

12.7

12.7

12.7

C

in

+

C

out

+

(R1)

Adj Down

R2

Adjust

Up

Vo

COM

COM

Vin

L

O

A

D

PT6650

11,12,13

14

7,8,9,10

4,5,6

Vin

V o

GND

Vo(adj)

STBY

3

Vsense

1