GE Industrial Solutions LC-LW015-Series - Manual (Page 16)

16 16 Lineage Power
Data Sheet
March 27, 2008 18 Vdc to 36 Vdc or 36 Vdc to 75 Vdc Inputs, 10 W and 15 W
LC/LW010- and LC/LW015-Series Power Modules:
Feature Descriptions
(continued)
Output Voltage Adjustment (Optional on
Single-Output Units)
Output voltage set-point adjustment allows the user to
increase or decrease the output voltage set point of a
module. This is accomplished by connecting an exter-
nal resistor between the TRIM pin and either the V
O
(+)
or V
O
(–) pins. With an external resistor between the
TRIM and V
O
(+) pins (R adj-down ), the output voltage set
point (V
O, adj
) decreases (see Figure 39). The following
equation determines the required external resistor
value to obtain an output voltage change from V
O, nom
to V
O, adj
:
where R adj-down is the resistance value connected
between TRIM and V
O
(+), and G, H, and L are defined
in the following table.
8-715(C).e
Figure 39. Circuit Configuration to Decrease
Output Voltage
With an external resistor connected between the TRIM
and V
O
(–) pins (R
adj-up
), the output voltage set point
(V
O, adj
) increases (see Figure 40). The following equa-
tion determines the required external resistor value to
obtain an output voltage from V
O, nom
to V
O, adj
:
where R adj-up is the resistance value connected
between TRIM and V
O
(–), and the values of G, H, K,
and L are shown in the following table:
The combination of the output voltage adjustment
and the output voltage tolerance cannot exceed 110%
(125% for the D) of the nominal output voltage between
the V
O
(+) and V
O
(–) terminals.
8-715(C).d
Figure 40. Circuit Configuration to Increase Output
Voltage
The L-Series power modules have a fixed current-limit
set point. Therefore, as the output voltage is adjusted
down, the available output power is reduced. In addi-
tion, the minimum output current is a function of the
output voltage. As the output voltage is adjusted down,
the minimum required output current can increase
(i.e., minimum power is constant).
Synchronization (Optional)
With external circuitry, the unit is capable of synchroni-
zation from an independent time base with a switching
rate of 256 kHz. Other frequencies may be available;
please consult the factory for application guidelines
and/or a description of the external circuit needed to
use this feature.
R
adj-down
V
O adj ,
L – ( )
G
V
O nom ,
V
O adj ,
– ( )
--------------------------------------- H – Ω =
V I (+)
V I (–)
V O (+)
V O (-)
TRIM
R adj-down
R LOAD
R
adj-up
GL
V
O adj ,
L – ( )
K – [ ]
----------------------------------------- H –
⎝ ⎠
⎛ ⎞
Ω =
G H K L
Lx010, 5A 5110 2050 2.5 2.5
Lx010, 5B 10,000 5110 9.5 2.5
Lx010, 5C 10,000 5110 NA 2.5
Lx010, 5D 5110 2050 0.76 1.23
Lx010, 5F 5110 2050 0.75 2.5
V I (+)
V I (-)
V O (+)
V O (-)
TRIM
R adj-up
R LOAD