Datasheet

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TYPICALCHARACTERISTICS
0
10
20
30
40
50
60
70
80
90
-50 -25 0 25 50 75 100 125 150
T -JunctionTemperature-°C
J
OnResistance-mW
V =12V
IN
V =4.5V
IN
0.8912
0.8910
0.8908
0.8906
0.8904
0.8902
0.8900
0.8898
−50 −25 0 25 50 75 100 125 150
V
ref
− Internal Voltage Reference − V
T
J
− Junction Temperature − 5C
VIN = 12 V
7.50
7.75
8
8.25
8.50
0 5 10 15 20 25
V -InputVoltage-V
I
CurrentLimit- A
T =25°C
J
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
700 kHz
600 kHz
500 kHz
400 kHz
300 kHz
200 kHz
I
O
> 0.5 A
Minimum Output Voltage − V
V
I
− Input Voltage − V
0
100
200
300
400
500
600
700
800
5 6 7 8 9
10 11 12 13 14 15 16 17 18 19 20
I
O
> 0.5 A
Maximum Switching Frequency − kHz
V
I
− Input Voltage − V
V
O
= 3.3 V
V
O
= 2.5 V
V
O
= 1.8 V
V
O
= 1.5 V
V
O
= 0.9 V
V
O
= 1.2 V
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
700 kHz
600 kHz
500 kHz
400 kHz
300 kHz
200 kHz
I
O
= 0 A
Minimum Output Voltage − V
V
I
− Input Voltage − V
0
100
200
300
400
500
600
700
800
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
I
O
< 0.1 A
Maximum Switching Frequency − kHz
V
I
− Input Voltage − V
V
O
= 3.3 V
V
O
= 2.5 V
V
O
= 0.9 V
V
O
= 1.8 V
V
O
= 1.5 V
V
O
= 1.2 V
50
75
100
125
150
175
200
225
200 300 400 500 600 700
RT Resistance − kW
Switching Frequency − kHz
0
2
4
6
8
10
12
14
0 5 10 15 20 25
− Output Voltage − V
V
O
V
I
− Input Voltage − V
TPS54550
SLVS623A–MARCH2006–REVISEDAPRIL2006
ONRESISTANCECURRENTLIMITINTERNALVOLTAGEREFERENCE
vsvsvs
JUNCTIONTEMPERATUREINPUTVOLTAGEJUNCTIONTEMPERATURE
Figure5.Figure6.Figure7.
MAXIMUMSWITCHING
MINIMUMOUTPUTVOLTAGEMINIMUMOUTPUTVOLTAGEFREQUENCY
vsvsvs
INPUTVOLTAGEINPUTVOLTAGEINPUTVOLTAGE
Figure8.Figure9.Figure10.
MAXIMUMSWITCHING
FREQUENCYMAXIMUMOUTPUTVOLTAGERTRESISTANCE
vsvsvs
INPUTVOLTAGEINPUTVOLTAGESWITCHINGFREQUENCY
Figure11.Figure12.Figure13.
13
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