GE Industrial Solutions QPW050-060 Series User Manual
Page 13
Data Sheet
February 2, 2011
QPW050/060 Series Power Modules; DC-DC converters
36-75Vdc Input; 1.2Vdc to 3.3Vdc Output
LINEAGE
POWER
13
Feature Description
(continued)
Output Voltage Set-Point Adjustment (Trim)
For output voltages: 1.5V – 3.3V
K
R
down
adj
2
.
10
%
510
For output voltage: 1.2V
K
R
down
adj
49
.
33
%
1
.
1299
Where,
100
%
,
,
nom
o
desired
nom
o
V
V
V
V
desired
= Desired output voltage set point (V).
With an external resistor connected between the
TRIM and SENSE(+) pins (Radj-up), the output
voltage set point (Vo,adj) increases (see Figure 37).
The following equation determines the required
external-resistor value to obtain a percentage output
voltage change of
%.
For output voltages: 1.5V – 3.3V
K
V
R
nom
o
up
adj
2
.
10
%
510
%
*
225
.
1
%
100
*
*
1
.
5
,
For output voltage: 1.2V
K
V
R
nom
o
up
adj
49
.
33
%
1
.
1299
%
*
6
.
0
%
100
*
*
769
.
9
,
Where,
100
%
,
,
nom
o
nom
o
desired
V
V
V
V
desired
= Desired output voltage set point (V).
The voltage between the Vo(+) and Vo(-) terminals
must not exceed the minimum output overvoltage
shut-down value indicated in the Feature
Specifications table. This limit includes any increase
in voltage due to remote-sense compensation and
output voltage set-point adjustment (trim). See Figure
35.
Although the output voltage can be increased by both
the remote sense and by the trim, the maximum
increase for the output voltage is not the sum of both.
The maximum increase is the larger of either the
remote sense or the trim.
The amount of power delivered by the module is
defined as the voltage at the output terminals
multiplied by the output current. When using remote
sense and trim, the output voltage of the module can
be increased, which at the same output current would
increase the power output of the module. Care should
be taken to ensure that the maximum output power of
the module remains at or below the maximum rated
power.
Figure 36. Circuit Configuration to Decrease
Output Voltage .
Figure 37. Circuit Configuration to Increase
Output Voltage.
Examples:
To trim down the output of a nominal 3.3V
module (QPW050A0F) to 3.1V
100
3
.
3
1
.
3
3
.
3
%
V
V
V
∆% = 6.06
K
R
down
adj
2
.
10
06
.
6
510
R
adj-down
= 73.96
k
To trim up the output of a nominal 3.3V module
(QPW050A0F) to 3.6V
100
3
.
3
3
.
3
6
.
3
%
V
V
V