2 × 12a digital dual microdlynx, Non-isolated dc-dc power modules, Datasheet – GE Industrial Solutions 2 × 12A Digital Dual Output MicroDLynx User Manual
Page 15: Ω − = k vo rtrim 6 . 0 12

GE
Datasheet
2 × 12A Digital Dual MicroDlynx
TM
: Non-Isolated DC-DC Power Modules
4.5Vdc –14.4Vdc input; 0.51Vdc to 5.5Vdc output; 2 × 12A Output Current
February 14, 2014
©2014 General Electric Corporation. All rights reserved.
Page 15
Figure 41. Output Voltage vs. Input Voltage Set Point Area
plot showing limits where the output voltage can be set
for different input voltages.
V
O1
(+)
TRIM2
GND
R
trim2
LOAD
V
IN1
(+)
ON/OFF1
VS+1
SIG_GND
V
O2
(+)
VS+2
TRIM1
ON/OFF2
V
IN2
(+)
R
trim1
Caution – Do not connect SIG_GND to GND elsewhere in the
layout
Figure 42. Circuit configuration for programming output
voltage using an external resistor.
Without an external resistor between Trim and SIG_GND
pins, each output of the module will be 0.6Vdc.To calculate
the value of the trim resistor, Rtrim for a desired output
voltage, should be as per the following equation:
(
)
Ω
−
=
k
Vo
Rtrim
6
.
0
12
Rtrim is the external resistor in kΩ
Vo is the desired output voltage.
Table 1 provides Rtrim values required for some common
output voltages.
Table 1
V
O, set
(V)
Rtrim (KΩ)
0.6 Open
0.9 40
1.0 30
1.2 20
1.5 13.33
1.8 10
2.5 6.316
3.3 4.444
5.0 2.727
Digital Output Voltage Adjustment
Please see the Digital Feature Descriptions section.
Remote Sense
The power module has a Remote Sense feature to minimize
the effects of distribution losses by regulating the voltage
between the sense pins (VS+ and VS-) for each of the 2
outputs. The voltage drop between the sense pins and the
VOUT and GND pins of the module should not exceed 0.5V. If
there is an inductor being used on the module output, then
the tunable loop feature of the module should be used to
ensure module stability with the proposed sense point
location. If the simulation tools and loop feature of the
module are not being used, then the remote sense should
always be connected before the inductor. The sense trace
should also be kept away from potentially noisy areas of the
board
Analog Voltage Margining
Output voltage margining can be implemented in the
module by connecting a resistor, R
margin-up
, from the Trim pin
to the ground pin for margining-up the output voltage and
by connecting a resistor, R
margin-down
, from the Trim pin to
output pin for margining-down. Figure 43 shows the circuit
configuration for output voltage margining. The POL
Programming Tool, available
at www.lineagepower.com
under the Downloads section, also calculates the values of
R
margin-up
and R
margin-down
for a specific output voltage and %
margin. Please consult your local Lineage Power technical
representative for additional details.
0
2
4
6
8
10
12
14
16
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
Input V
o
ltage
(v
)
Output Voltage (V)
Lower
Upper
Vo1
MODULE
SIG_GND
Trim1
Q1
Rtrim1
Rmargin-up
Q2
Rmargin-down