FW330 Lineage Power, FW330 Datasheet - Page 15

• Manufacturer Part Number: FW330
• Description: Fw330 Power Modules Dc-dc Converters 36 To 75 Vdc Input, 3.6, 3.3, 2.5, 2.0, Or 1.8 Vdc Output; 180 W To 330 W
• Manufacturer: Lineage Power

April 3, 2008
Feature Descriptions
Output Voltage Set-Point Adjustment
(Trim)
Figure 25. Resistor Selection for Increased Output
Output Overvoltage Protection
The output overvoltage shutdown consists of control
circuitry, independent of the primary regulation loop,
that monitors the voltage on the output terminals. The
control loop of the over voltage protection has a higher
voltage set point than the primary loop (see Feature
Specifications table). This provides a redundant volt-
age control that reduces the risk of output overvoltage
and latches the converter off if an overvoltage occurs.
Recovery from latched shutdown is accomplished by
cycling the dc input power off for at least 1.0 second or
by toggling the primary or secondary referenced
remote on/off signal for at least 1.0 second.
The overvoltage shutdown set point can be lowered by
placing a resistor between the overvoltage trim
(OVTRIM) pin and SENSE(–) pin. This feature is useful
if the output voltage of the converter has been trimmed
down and a corresponding reduction in overvoltage trip
point is desired.
The resistance required from a given overvoltage nom-
inal set point is derived from the following equation:
Lineage Power
100k
R
10k
1M
1k
ov
0
-
(continued)
adj
=
Voltage
⎛
⎝
4.3 2 V
------------------------------------ -
% CHANGE IN OUTPUT VOLTAGE (Δ%)
V
2
ov-set
1.8 V
2.0 V
2.5 V
–
–
ov-set
4.3
36 to 75 Vdc Input, 3.6, 3.3, 2.5, 2.0, or 1.8 Vdc Output; 180 W to 330 W
4
⎞ kΩ
⎠
(continued)
6
3.3 V
3.6 V
8
8-2820 (F)
10
Where:
R
V
Output Current Monitor
The CURRENT MON pin provides a dc voltage propor-
tional to the dc output current of the module given in
the Feature Specifications table. For example, on the
FW330Y1, the V/A ratio is set at 45 mV/A ± 10% @
70 °C case. At a full load current of 100 A, the voltage
on the CURRENT MON pin is 4.5 V. The current moni-
tor signal is referenced to the SENSE(–) pin on the
secondary and is supplied from a source impedance of
approximately 20 kΩ. It is recommended that the CUR-
RENT MON pin be left open when not in use, although
no damage will result if the CURRENT MON pin is
shorted to secondary ground. Directly driving the CUR-
RENT MON pin with an external source will detrimen-
tally affect operation of the module and should be
avoided.
Module Synchronization
Any module can be synchronized to any other module
or to an external clock using the SYNC IN or SYNC
OUT pins. The modules are not designed to operate in
a master/slave configuration; that is, if one module
fails, the other modules will continue to operate.
SYNC IN Pin
This pin can be connected either to an external clock or
directly to the SYNC OUT pin of another module.
If an external clock signal is applied to the SYNC IN
pin, the signal must be a 500 kHz (±50 kHz) square
wave with a 4 Vp-p amplitude. Operation outside this
frequency band will detrimentally affect the perfor-
mance of the module and must be avoided.
If the SYNC IN pin is connected to the SYNC OUT pin
of another module, the connection should be as direct
as possible, and the V
shorted together.
Unused SYNC IN pins should be tied to V
SYNC IN pin is not used, the module will operate from
its own internal clock.
ov-set
ov-adj
is the value of an external resistor between the
OVTRIM pin and SENSE(–) pin.
is the nominal adjusted set point of the overvolt-
age shutdown threshold.
I
(–) pins of the modules must be
I
(–). If the
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