JFW100B Lineage Power, JFW100B Datasheet - Page 13

• Manufacturer Part Number: JFW100B
• Manufacturer: Lineage Power

April 2008
Feature Descriptions
Output Voltage Set-Point Adjustment
(Trim)
Figure 23. Resistor Selection for Decreased
With an external resistor connected between the
V
age set point (V
Figure 24. Circuit Configuration to Increase
The following equation determines the required exter-
nal-resistor value to obtain a percentage output voltage
change of ý%.
The test results for this configuration are displayed in
Figure 25.
Lineage Power
O
TRIM and SENSE(+) pins (R
100k
R
100
10k
1M
1k
V
ON/OFF
CASE
V
adj-up
I
I
(+)
(–)
0
(continued)
Output Voltage
Output Voltage
=
⎛
⎝
SENSE(+)
SENSE(–)
V
------------------------------------- -
% CHANGE IN OUTPUT VOLTAGE (Δ%)
O, adj
V
O
O
1.225Δ%
(
10
V
TRIM
V
100
O
O
) increases (see Figure 24).
(+)
(–)
dc-dc Converters; 36 Vdc to 75 Input, Vdc 12 Vdc Output; 50 W to 150 W
+
Δ%
)
20
(continued)
–
adj-up
(
--------------------------------- -
100
R
adj-up
), the output volt-
Δ%
+
2Δ%
30
R
)
⎞ kΩ
⎠
LOAD
8-715 (C).g
8-879 (C)
40
The voltage between the V
must not exceed the output overvoltage shutdown volt-
age. This limit includes any increase in voltage due to
remote-sense compensation and output voltage set-
point adjustment (trim).
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. Consult the factory if you
need to increase the output voltage more than the
above limitation.
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.
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 clamp has a higher voltage set point
than the primary loop (see Feature Specifications
table). This provides a redundant voltage control that
reduces the risk of output overvoltage and latches the
converter off if an overvoltage occurs.
100k
10M
10k
1M
0
Voltage
% CHANGE IN OUTPUT VOLTAGE (Δ%)
2
4
O
(+) and V
6
O
(–) terminals
8
8-2083 (C)
10
13