Datasheet

TPS78825, TPS78833
SLVS382A – JUNE 2001 – REVISED JULY 2001
5
www.ti.com
TYPICAL CHARACTERISTICS
Figure 10
3
OUTPUT VOLTAGE, ENABLE VOLTAGE
vs
TIME (START-UP)
V
O
t – Time – ms
0302010 40 50 7060 80 90 100
– Output Voltage – V
V
I
= 4.3 V
V
O
= 3.3 V
I
O
= 150 mA
C
o
= 10 µF
T
J
= 25°C
Enable Voltage – V
1
5
0
0
2
C
(SR)
= 0.01 µF
C
(SR)
= 0.1 µF
Figure 11
5.3
LINE TRANSIENT RESPONSE
t – Time – µs
0604020 80 100 140120 160 180 200
V
O
= 3.3 V
C
o
= 10 µF
4.3
20
0
V
O
– Output Voltage – mV V
I
– Input Voltage – V
–20
dv
dt
=
0.2 V
µs
Figure 12
t – Time – µs
LOAD TRANSIENT RESPONSE
0
0604020 80 100 140120 160 180
100
0
–50
–100
V
O
Output Voltage – mV
∆
– Change In
50
200
– Output Current – mA
I
O
V
I
= 4.3 V
V
O
= 3.3 V
C
o
= 10 µF
200
dI
dt
=
0.075 A
µs
1
0 60 90 120 150
100
I
O
– Output Current – mA
ESR – Equivalent Series Resistance – Ω
10
TYPICAL REGIONS OF STABILITY
EQUIVALENT SERIES RESISTANCE (ESR)
vs
OUTPUT CURRENT
0.1
V
I
= 4.3 V
V
O
= 3.3 V
C
o
= 4.7 µF
Region of Stability
Region of Instability
Fi
g
ure 13
I
O
– Output Current – mA
1
0 60 90 120 150
100
10
V
I
= 4.3 V
V
O
= 3.3 V
C
o
= 10 µF
TYPICAL REGIONS OF STABILITY
EQUIVALENT SERIES RESISTANCE (ESR)
vs
OUTPUT CURRENT
Region of Instability
Region of Stability
0.1
Figure 14
ESR – Equivalent Series Resistance – Ω