GE Industrial Solutions 12A Analog SlimLynx Open Frame - Manual (Page 14)

GE
Data Sheet
12A Analog SlimLynx TM Open Frame: Non-Isolated DC-DC Power Modules
3Vdc –14.4Vdc input; 0.6Vdc to 5.5Vdc output; 12A Output Current
February 19, 2014 ©2014 General Electric Corporation. All rights reserved. Page 14
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,
the 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
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-). The voltage drop
between the sense pins and the VOUT and GND pins of the
module should not exceed 0.5V.
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 GE Critical Power
technical representative for additional details.
Figure 43. Circuit Configuration for margining Output
voltage.
Output Voltage Sequencing
The power module includes a sequencing feature, EZ-
SEQUENCE that enables users to implement various types of
output voltage sequencing in their applications. This is
accomplished via an additional sequencing pin. When not
using the sequencing feature, leave it unconnected.
The voltage applied to the SEQ pin should be scaled down by
the same ratio as used to scale the output voltage down to
the reference voltage of the module. This is accomplished by
an external resistive divider connected across the
sequencing voltage before it is fed to the SEQ pin as shown
in Fig. 44. In addition, a small capacitor (suggested value
100pF) should be connected across the lower resistor R1.
For all SlimLynx modules, the minimum recommended delay
between the ON/OFF signal and the sequencing signal is
10ms to ensure that the module output is ramped up
according to the sequencing signal. This ensures that the
module soft-start routine is completed before the
sequencing signal is allowed to ramp up.
Figure 44. Circuit showing connection of the sequencing
signal to the SEQ pin.
When the scaled down sequencing voltage is applied to the
SEQ pin, the output voltage tracks this voltage until the
Vo
MODULE
SIG_GND
Trim
Q1
Rtrim
Rmargin-up
Q2
Rmargin-down
100 pF
SlimLynx Module
R1=Rtrim
20K
SIG_GND
SEQ
SEQ
V