DS_E36SC3R335_03282013

8

FEATURES DESCRIPTIONS (CON.)

If the remote sense feature is not used to regulate the

output at the point of load, please connect SENSE(+) to

Vo(+) and SENSE(–) to Vo(–) at the module.

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 does not exceed the maximum rated

power.

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 16: 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









−

∆

=

−

K

down

Rtrim

2

.

10

511

Ex. When Trim-down -10% (3.3V×0.9=2.97V)

()

()

Ω

=

Ω









−

=

−

K

K

down

Rtrim

9

.

40

2

.

10

10

511

Figure 17: 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

−

∆

−

∆

∆

+

=

−

K

up

Rtrim

2

.

10

511

1.225

)

(100

Vo

11

.

5

Ex. When Trim-up +10% (3.3V×1.1=3.63V)

()

Ω

=

−

−

×

+

×

×

=

−

K

up

Rtrim

12

.

90

2

.

10

10

511

10

225

.

1

)

10

100

(

3

.

3

11

.

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.