GE Industrial Solutions 6A Austin MicroLynx II - Manual (Page 14)

GE Energy
Data Sheet
6A Austin MicroLynx TM II: Non-Isolated DC-DC Power Modules
8.3Vdc –14Vdc input; 0.75Vdc to 5.5Vdc output; 6A Output Current
October 16, 2012 ©2012 General Electric Company. All rights reserved. Page 14
Feature Descriptions (continued)
Voltage Sequencing
Austin MicroLynx TM II 12V series of modules include a
sequencing feature, EZ-SEQUENCE TM 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, either
tie the SEQ pin to V
IN
or leave it unconnected.
When an analog voltage is applied to the SEQ pin, the output
voltage tracks this voltage until the output reaches the set-
point voltage. The SEQ voltage must be set higher than the
set-point voltage of the module. The output voltage follows the
voltage on the SEQ pin on a one-to-one volt basis. By
connecting multiple modules together, customers can get
multiple modules to track their output voltages to the voltage
applied on the SEQ pin.
For proper voltage sequencing, first, input voltage is applied to
the module. The On/Off pin of the module is left unconnected
(or tied to GND for negative logic modules or tied to V
IN
for
positive logic modules) so that the module is ON by default.
After applying input voltage to the module, a minimum of
10msec delay is required before applying voltage on the SEQ
pin. During this time, potential of 50mV (± 10 mV) is maintained
on the SEQ pin. After 10msec delay, an analog voltage is
applied to the SEQ pin and the output voltage of the module
will track this voltage on a one-to-one volt bases until output
reaches the set-point voltage. To initiate simultaneous
shutdown of the modules, the SEQ pin voltage is lowered in a
controlled manner. Output voltage of the modules tracks the
voltages below their set-point voltages on a one-to-one basis.
A valid input voltage must be maintained until the tracking and
output voltages reach ground potential to ensure a controlled
shutdown of the modules.
When using the EZ-SEQUENCE
TM feature to control start-up of
the module, pre-bias immunity feature during start-up is
disabled. The pre-bias immunity feature of the module relies
on the module being in the diode-mode during start-up. When
using the EZ-SEQUENCE
TM feature, modules goes through an
internal set-up time of 10msec, and will be in synchronous
rectification mode when voltage at the SEQ pin is applied. This
will result in sinking current in the module if pre-bias voltage is
present at the output of the module. When pre-bias immunity
during start-up is required, the EZ-SEQUENCE
TM feature must
be disabled. For additional guidelines on using EZ-SEQUENCE TM
feature of Austin MicroLynx TM II 12V, contact A GE Energy
technical representative for preliminary application note on
output voltage sequencing using Austin Lynx II series.