Datasheet

DS_E36SR12004_06192012
9
Output Voltage Adjustment (TRIM)
To increase or decrease the output voltage set point,
connect an external resistor between the TRIM pin
and either the SENSE(+) or SENSE(-). The TRIM
pin should be left open if this feature is not used.
Figure 18: Circuit configuration for trim-down (decrease
output voltage)
If the external resistor is connected between the
TRIM and SENSE (-) pins, the output voltage set
point decreases (Fig. 18). The external resistor
value required to obtain a percentage of output
voltage change △% is defined as:
()
Ω−
∆
=− KdownRtrim 10
510
Ex. When Trim-down -20% (12V×0.8=9.6V)
() Ω=−=− KdownRtrim 5.1510
20
510
Figure 19: Circuit configuration for trim-up (increase output
voltage
If the external resistor is connected between the TRIM
and SENSE (+) the output voltage set point increases
(Fig. 19). The external resistor value required to obtain
a percentage output voltage change △% is defined
as:
()
Ω−
∆
−
∆
∆+
=− KupRtrim 10
510
1.225
) (100 Vo1.5
Ex. When Trim-up +10% (12V×1.1=13.2V)
()
Ω=−−
×
+
×
×
=− KupRtrim 55.48810
10
510
101.225
) 10(100 121.5
The output voltage can be increased by both the remote
sense and the trim, however the maximum increase is
the larger of either the remote sense or the trim, not the
sum of both.
When using remote sense and trim, the output voltage
of the module is usually increased, which increases the
power output of the module with the same output
current.
Care should be taken to ensure that the maximum
output power of the module remains at or below the
maximum rated power.