Data Sheet
ADP124/ADP125
–10
5
4
3
2
1
0
–20
I
I
I
I
I
I
= 100µA
= 1mA
= 10mA
= 100mA
= 300mA
= 500mA
OUT
OUT
OUT
OUT
OUT
OUT
V
= 4.2V
OUT
V
–30
–40
–50
–60
–70
–80
–90
–100
= 3.3V
OUT
V
= 2.8V
OUT
V
V
C
= V
+ 1V
= 50mV
IN
RIPPLE
= C
OUT
= 1µF
IN
OUT
10
100
1k
FREQUENCY (Hz)
10k
100k
10
100
1k
10k
100k
1M
10M
FREQUENCY (Hz)
Figure 19. Power Supply Rejection Ratio vs. Frequency, VOUT = 4.2 V, VIN = 5.2 V
Figure 22. Output Noise Spectrum, VIN = 5 V
–10
70
65
60
55
50
45
40
35
30
25
20
V
V
V
V
V
V
= 2.8V, I
= 3.3V, I
= 4.2V, I
= 2.8V, I
= 3.3V, I
= 4.2V, I
= 10mA
= 10mA
= 10mA
= 500mA
= 500mA
= 500mA
V
V
= 4.2V
= 3.3V
OUT
OUT
OUT
OUT
OUT
OUT
OUT
OUT
OUT
OUT
OUT
OUT
OUT
–20
–30
–40
–50
–60
–70
–80
–90
–100
OUT
V
= 2.8V
OUT
V
V
C
= V
+ 1V
= 50mV
IN
RIPPLE
= C
OUT
= 1µF
IN
OUT
10
100
1k
10k
100k
1M
10M
0.001
0.01
0.1
1
10
100
1k
I
LOAD
(mA)
FREQUENCY (Hz)
Figure 20. Power Supply Rejection Ratio vs. Frequency,
Various Output Voltages and Load Currents
Figure 23. Output Noise vs. Load Current and Output Voltage, VIN = 5 V
–10
–20
–30
–40
–50
–60
–70
–80
–90
–100
I
OUT
V
V
V
V
= 3.1V, I
= 3.3V, I
= 3.8V, I
= 4.8V, I
= 10mA
= 10mA
= 10mA
= 10mA
IN
IN
IN
IN
OUT
OUT
OUT
OUT
1mA TO 500mA LOAD STEP
1
V
OUT
2
V
V
V
V
= 3.1V, I
= 3.3V, I
= 3.8V, I
= 4.8V, I
= 500mA
= 500mA
= 500mA
= 500mA
IN
IN
IN
IN
OUT
OUT
OUT
OUT
V
V
= 4V
= 3.3V
IN
OUT
CH1 500mA Ω B CH2 50.0mV
M40.0µs
9.800%
A CH1 200mA
B
W
W
10
100
1k
10k
100k
1M
10M
T
FREQUENCY (Hz)
Figure 21. Power Supply Rejection Ratio vs. Headroom Voltage (VIN − VOUT),
OUT = 2.8 V
Figure 24. Load Transient Response, COUT = 1 μF
V
Rev. C | Page 9 of 20
ADI [ ADI ]
