Datasheet

TPS54380
SLVS454B − JANUARY 2003 − REVISED FEBRUARY 2005
www.ti.com
7
TYPICAL CHARACTERISTICS
Fi
g
ure 1
0
20
40
60
80
100
120
−40 0 25 85 125
I
O
= 3 A
V
I
= 3.3 V
T
J
− Junction Temperature − °C
Drain-Source On-State Resistance −
DRAIN-SOURCE ON-STATE RESISTANCE
vs
JUNCTION TEMPERATURE
Ω
Fi
g
ure 2
0
20
40
60
80
100
−40 0 25 85 125
I
O
= 3 A
V
I
= 5 V
T
J
− Junction Temperature − °C
Drain-Source On-State Resistance −
DRAIN-SOURCE ON-STATE RESISTANCE
vs
JUNCTION TEMPERATURE
Ω
Fi
g
ure 3
450
−40 0 25
f − Internally Set Oscillator Frequency −kHz
550
INTERNALLY SET OSCILLATOR
FREQUENCY
vs
JUNCTION TEMPERATURE
750
85 125
650
350
250
T
J
− Junction Temperature − °C
Figure 4
400
−40 0 25
f − Externally Set Oscillator Frequency − kHz
500
EXTERNALLY SET OSCILLATOR
FREQUENCY
vs
JUNCTION TEMPERATURE
800
85 125
700
300
200
T
J
− Junction Temperature − °C
600
RT = 68 k
RT = 100 k
RT = 180 k
Figure 5
0.889
−40 0 25
− Voltage Reference − V
VOLTAGE REFERENCE
vs
JUNCTION TEMPERATURE
0.895
85 125
0.893
0.887
0.885
T
J
− Junction Temperature − °C
0.891
V
ref
Figure 6
0.8850
0.8870
0.8890
0.8910
0.8930
0.8950
3456
f = 350 kHz
T
A
= 85°C
V
I
− Input Voltage − V
− Output Voltage Regulation − V
OUTPUT VOLTAGE REGULATION
vs
INPUT VOLTAGE
V
O
Figure 7
f − Frequency − Hz
60
40
0
0 10 100 1 k 10 k 100 k 1 M
Gain − dB
80
100
ERROR AMPLIFIER
OPEN LOOP RESPONSE
140
10 M
120
20
−20
Phase − Degrees
0
−20
−40
−60
−80
−100
−120
−140
−160
−180
−200
R
L
= 10 kΩ,
C
L
= 160 pF,
T
A
= 25°C
Phase
Gain
0
0.25
0.5
0.75
1
1.25
1.5
1.75
2
2.25
01234
I
L
− Load Current − A
Device Power Losses − W
DEVICE POWER LOSSES
vs
LOAD CURRENT
T
J
− 125°C
f
s
= 700 kHz
V
I
= 3.3 V
V
I
= 5 V
Figure 8