GE Industrial Solutions JNC350R Series - Manual (Page 9)

Data Sheet
August 9, 2010
JNC350R Power Modules; DC-DC Converters
18 – 36 Vdc Input; 28Vdc Output; 350W Output
LINEAGE POWER 9
Feature Description (continued)
Examples:
To trim down the output of a nominal 28V module to
16.8V
100
28
8 . 16 28
%


 
V
V V
∆% = 40
 





 
 k R
down adj
2
40
100
R
adj - down
= 0.5 k 
To trim up the output of a nominal 28V module to
30.8V
100
28
28 8 . 30
%


 
V
V V
Δ% = 10




  


 


k R
up adj 10
) 10 2 ( 100 (
10 225 . 1
) 10 100 ( 28
R
adj - up
= 239.4 kΩ
Modules with the –T Option
Trim Down – Decrease Output Voltage
With an external resistor (R
adj-down
) between the TRIM
and SENSE(+) pins, the output voltage set point
(V
o,adj
) decreases (see Figure 15). The following
equation determines the required external-resistor
value to obtain a percentage output voltage change of
%.
For output voltages: 28V
 








 k R
down adj
2 . 111
%
45 . 10631
Where,
100 %
,
, 

 
nom o
desired nom o
V
V V
V
desired
= Desired output voltage set point (V).
Figure 15. Circuit Configuration to Decrease
Output Voltage, JNC350R-T option.
Trim Up – Increase Output Voltage
With an external resistor ( R
adj-up
) connected between
the SENSE(-) and TRIM pins , the output voltage set
point ( V
o, ad j
) increases (see Figure 16).
The following equation determines the required
external-resistor value to obtain a percentage output
voltage change of
%.
For output voltages: 28V
 







 k R
up adj
%
5 . 488
Where,
100 %
,
, 

 
nom o
nom o desired
V
V V
V
desired
= Desired output voltage set point (V).
Figure 16. Circuit Configuration to Increase
Output Voltage, JNC350Rx-T option.