Delta Electronics H48SL manual Features Descriptions Con, Output Voltage Adjustment TRIM, ⎝ ∆%

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FEATURES DESCRIPTIONS (CON.)

FEATURES DESCRIPTIONS (CON.)

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 22: 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. 22) The external resistor value required to obtain a percentage of output voltage change % is defined as:

Rtrim down=

100

ΚΩ

2

 

∆%

 

 

Ex. When Trim-down -20%(1.5V×0.8=1.2V)

Vo

:= 1.5 V

∆ := 20

100

− 2 = 3

K Ω

 

 

Figure 23: 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. 23). The external resistor value required to obtain a percentage output voltage change % is defined as:

Vo⋅(100 + ∆%)

 

100 + 2∆%

 

Rtrim up=

 

 

ΚΩ

1.225⋅∆%

 

∆%

 

Ex. When Trim-up +10%(1.5V×1.1=1.65V)

Vo := 1.5V

∆ := 10

 

Vo⋅(100 + ∆ )

100 + 2⋅∆

= 1.469 KΩ

1.225⋅∆

 

 

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.

DS_H48SL1R560_10302006

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Contents DATASHEET DSH48SL1R56010302006 FEATURESOPTIONS APPLICATIONSDYNAMIC CHARACTERISTICS TECHNICAL SPECIFICATIONSINPUT CHARACTERISTICS OUTPUT CHARACTERISTICSELECTRICAL CHARACTERISTICS CURVES Figure 7 Turn-on transient at zero load current 2 ms/div. Top For Negative Remote On/Off LogicFor Positive Remote On/Off Logic Figure 5 Turn-on transient at zero load current 2 ms/div. TopFigure 8 Output voltage response to step-change in load current 75%-50%-75% of Io, max di/dt = 0.1A/µs. Load cap 10µF, tantalum capacitor and 1µF ceramic capacitor. Top Trace Vout 100mV/div, Bottom Trace Iout 10A/div. Scope measurement should be made using a BNC cable length shorter than 20 inches. Position the load between 51 mm to 76 mm 2 inches to 3 inches from the module Figure 13 Output voltage noise and ripple measurement test setup Figure 14 Output voltage ripple at nominal input voltage and THERMAL CURVES NO HEATSINK, EITHER ORIENTATION Input Source Impedance Safety ConsiderationsSoldering and Cleaning Considerations DESIGN CONSIDERATIONSOver-Temperature Protection FEATURES DESCRIPTIONSOver-Current Protection Over-Voltage Protection⎝ ∆% FEATURES DESCRIPTIONS CONOutput Voltage Adjustment TRIM Thermal Derating Thermal Testing SetupTHERMAL CONSIDERATIONS Function Pin SpecificationMECHANICAL DRAWING NameMODEL NAME WARRANTYPART NUMBERING SYSTEM MODEL LIST