Datasheet

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t − Time − 20 ms/div
V
OU
T
(1 V/div)
V
IN
(10 V/div)
I
IN
(100 mA/div)
OutputVoltageTrimAdjustment
PTMA403033
PTMA402050
PTMA401120
SLTS259B–FEBRUARY2006–REVISEDMAY2007
APPLICATIONINFORMATION(continued)
Figure13.Power-upWaveforms
Anexternalresistorisrequiredtoincreaseordecreasetheoutputvoltagesetpointofthemoduleby± 10 %.
Theresistor,R
TRIM
,mustbeconnectedbetweentheTRIMpin(pin 5)andV
O
+(pin4)todecreasetheoutput
voltage,orbetweentheTRIMpinandV
O
–(pin 6)toincreasetheoutputvoltage.A0.05-Wratedresistorcanbe
used.Thetoleranceshouldbe1%,withatemperaturestabilityof100ppm/°C(orbetter).Placetheresistor
closetotheconverterandconnectitusingdedicatedPCBtraces(seeFigure14).Table1givesthenearest
standardvalueofexternalresistorforthecommonvoltageswithineachmodel'sadjustrange.
Table1.StandardValuesofR
TRIM
forCommonOutputVoltages
PTMA403033PTMA402050PTMA401120
V
O
R
TRIM
(kΩ)V
O
R
TRIM
(kΩ)V
O
R
TRIM
(kΩ)
(required)(required)(required)
downupdownupdownup
3.0V118—4.5V18.7—10.8V64.9—
3.1V187—4.6V24.9—11.0V80.6—
3.2V392—4.7V35.7—11.2V105—
3.3Vopenopen4.8V57.6—11.4V143—
3.4V—2494.9V121—11.6V221—
3.5V—1245.0Vopenopen11.8V464—
3.6V—82.55.1V—12412.0Vopenopen
———5.2V—61.912.2V—118
———5.3V—40.212.4V—57.6
———5.4V—29.412.6V—36.5
———5.5V—23.212.8V—26.1
——————13.0V—19.6
——————13.2V—15.8
11
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