GE Industrial Solutions 12V Mega TLynx - Manual (Page 12)

Data Sheet
May 4, 2012 12V Mega TLynx TM : Non-Isolated DC-DC Power Modules:
6.0 – 14Vdc Input; 0.8Vdc to 3.63Vdc Output; 30A output current
LINEAGE POWER 12
Overtemperature Protection
To provide protection in a fault condition, the unit is
equipped with a thermal shutdown circuit. The unit
will shutdown if the overtemperature threshold of
125
o C is exceeded at the thermal reference point
T
ref
. The thermal shutdown is not intended as a
guarantee that the unit will survive temperatures
beyond its rating. Once the unit goes into thermal
shutdown it will then wait to cool before attempting
to restart.
Input Undervoltage Lockout
At input voltages below the input undervoltage
lockout limit, the module operation is disabled. The
module will begin to operate at an input voltage
above the undervoltage lockout turn-on threshold.
Output Voltage Programming
The output voltage of the 12V Mega TLynx TM can
be programmed to any voltage from 0.8dc to
3.63Vdc by connecting a resistor (shown as R
trim
in
Figure 31) between Trim and GND pins of the
module. Without an external resistor between Trim
and GND pins, the output of the module will be
0.8Vdc. To calculate the value of the trim resistor,
R
trim
for a desired output voltage, use the following
equation:
Ω




−
=
8 . 0
8000
Vo
R
trim
R
trim
is the external resistor in Ω
Vo is the desired output voltage
By using a ±0.5% tolerance trim resistor with a TC
of ±100ppm, a set point tolerance of ±1.5% can be
achieved as specified in the electrical specification.
Table 1 provides Rtrim values required for some
common output voltages. The POL Programming
Tool, available at
www.lineagepower.com under the
Design Tools section, helps determine the required
external trim resistor needed for a specific output
voltage.
Table 1
V
O, set
(V) Rtrim (KΩ)
0.8 Open
1.0 40
1.2 20
1.5 11.429
1.8 8
2.5 4.706
3.3 3.2
V
O
(+)
TRIM
GND
R
tri m
LOAD
V
IN
(+)
ON/OFF
SENSE
Figure 31. Circuit configuration to program
output voltage using an external resistor.
Remote Sense
The 12V Mega TLynx TM power modules have a
Remote Sense feature to minimize the effects of
distribution losses by regulating the voltage at the
SENSE pin. The voltage between the SENSE pin
and VOUT pin must not exceed 0.5V. Note that the
output voltage of the module cannot exceed the
specified maximum value. This includes the voltage
drop between the SENSE and Vout pins. When the
Remote Sense feature is not being used, connect
the SENSE pin to the VOUT pin.
Voltage Margining
Output voltage margining can be implemented in
the 12V Mega TLynx
TM modules 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 32 shows
the circuit configuration for output voltage
margining. The POL Programming Tool, available
at
www.lineagepower.com under the Design Tools
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.
Monotonic Start-up and Shutdown
The 12V Mega TLynx TM modules have monotonic
start-up and shutdown behavior for any combination
of rated input voltage, output current and operating
temperature range.
Startup into Pre-biased Output
The 12V Mega TLynx TM modules can start into a
prebiased output as long as the prebias voltage is
0.5V less than the set output voltage. Note that
prebias operation is not supported when output
voltage sequencing is used.