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ProgrammingtheTPS71501AdjustableLDORegulator
V
输出
V
REF
1
R1
R2
(3)
R1
V
输出
V
REF
1
R2
(4)
输出 voltAGE
程序编制 手册
输出
电压
R1 R2
1.8 v
2.8 v
5.0 v
392 m
Ω
1.07 m
Ω
2.55 m
Ω
806 k
Ω
806 k
Ω
806 k
Ω
V
输出
V
在
FB
R1
R2
地
在
TPS715A01
0.1
µ
F
0.47
µ
F
输出
TPS715A01
TPS715A33
SBVS047A–MAY2004–REVISEDDECEMBER2004
TheoutputvoltageoftheTPS715A01adjustableregulatorisprogrammedusinganexternalresistordivideras
showninfigure15.theoutputvoltageiscalculatedusingequation3:
在哪里:
•
V
REF
=1.205vtyp(theinternalreferencevoltage)
resistorsr1andr2shouldbechosenforapproximately1.5-µadividercurrent.lowervalueresistorscanbe
usedforimprovednoiseperformance,butthesolutionconsumesmorepower.higherresistorvaluesshouldbe
avoidedasleakagecurrentinto/outoffbacrossr1/r2createsanoffsetvoltagethatartificiallyin-
creases/decreasesthefeedbackvoltageandthuserroneouslydecreases/increasesv
O
.therecommended
designprocedureistochooseR2=1M
Ω
tosetthedividercurrentat1.5µa,andthencalculater1using
equation4:
figure15.tps715a01adjustableldoregulatorprogramming
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