QBDW033A0B41Z Datasheet, PDF (9/17 Pages) Lineage Power Corporation – QBDW033A0B Series Power Modules; DC-DC Converters

Advanced Data Sheet
February 10, 2011
QBDW033A0B Series Power Modules; DC-DC Converters
36-75V_dc Input; 9.6-12V_dc Output; 33A Output Current
Feature Descriptions (continued)
Remote Sense
Remote sense minimizes the effects of distribution losses
by regulating the voltage at the remote-sense connections
(See Figure 11). The voltage between the remote-sense
pins and the output terminals must not exceed the output
voltage sense range given in the Feature Specifications
table:
[VO(+) – VO(–)] – [SENSE(+) – SENSE(–)]  0.5 V
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 (Maximum rated power = Vo,set x
Io,max).
SENSE(+)
SENSE(–)
SUPPLY _II
CONTACT
RESISTANCE
VI(+)
VI(-)
VO(+)
VO(–)
IO
LOAD
CONTACT AND
DISTRIBUTION LOSSE
Figure 11. Circuit Configuration for remote sense
.
Configurable Control Pins
The QBDW033A0B contains two configurable control pins,
T/C1 and C2, referenced to the module secondary
SIGGND. See Mechanical Views for pin locations. The
following table list the available factory configurations for
the functions assigned to these pins. Additional
configurations can accomplished via the PMBus interface.
Following the tables, there is a feature description for each
function.
Pin Designation/Function
T/C1
Trim TM
Load Share CS
C2
Power Good PG
Power Good PG
Factory
Configuration
Modules without -P
Modules with -P
C2 Pin Designation/Function Configurable via PMBus
Power Good PG
On/Off(o)
Trim, Output Voltage Programming, TM
Trimming allows the output voltage set point to be
increased or decreased; this is accomplished by connecting
an external resistor between the TRIM pin and either the
VO(+) pin or the VO(-) pin.
VO(+)
Rtrim-up
T/C 1
QBDW033A0B
V O( -)
LO AD
Rtri m-dow n
Figure 12. Circuit Configuration to Trim Output Voltage.
Connecting an external resistor (Rtrim-down) between the
T/C1 pin and the Vo(-) (or Sense(-)) pin decreases the
output voltage set point. To maintain set point accuracy, the
trim resistor tolerance should be ±1.0%.
The following equation determines the required external
resistor value to obtain a percentage output voltage change
of Δ%
R_{trim  down}

 511
 _{ %}

10
.22



Where
%


V_o
,
set ^{ V}desired
V_{o, set}
 ^{ 100}
For example, to trim-down the output voltage of the module
by 20% to 9.6V, Rtrim-down is calculated as follows:
 %  20
R_{trim  down}

 511
 ₂₀
 10.22_{}
R_{trim down}  15 .3k
Connecting an external resistor (Rtrim-up) between the T/C1
pin and the VO(+) (or Sense (+)) pin increases the output
voltage set point. The following equations determine the
required external resistor value to obtain a percentage
output voltage change of Δ%:
R_{trim  up}

 5.11  V_{o, set}  (100  %)


1.225  %

511
%
 10.22 _{}

Where
%


V _desired
V_o
,
 V_o
set
,
set
 ^{ 100}
For example, to trim-up the output voltage of the module by
5% to 12.6V, Rtrim-up is calculated is as follows:
%  5
R_{trim up}

 5.11  12 .0  (100

1.225  5
 5)

511
5

10
.22



R_{trim up}  102 .2
LINEAGE POWER
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