Low Power-Loss Voltage Regulators
PQ20WZ51/PQ20WZ11
Fig.11 Dropout Voltage vs. Junction
Temperature (PQ20WZ11)
0.18
Fig.12 Quiescent Current vs. Junction
Temperature
5
4
3
2
1
0
VIN=5V
IO=0A
0.17
0.16
0.15
0.14
0.13
0.12
0.11
VC=2.7V
R1=2kΩ
R2=500Ω
V
IN=3.135V, Vc=2.7V, R
1
=2kΩ, R
2
=500Ω, I =0.5A
O
0.1
–25
0
25
50
75
100 125
–25
0
25
50
75 100 125
Junction temperature T
j
(˚C)
Junction temperature Tj (˚C)
Fig.13 Ripple Rejection vs. Input Ripple
Fig.14 Ripple Rejection vs. Output Current
Frequency
(PQ20WZ51)
80
80
75
75
70
65
60
55
70
65
60
55
50
45
40
PQ20WZ11
PQ20WZ51
T
=25˚C
Vj =5V
RIN=2kΩ
50
45
40
R1=0.5kΩ
I
O
=0.3A
T
=25˚C
Vj =5V
ei2(rms)=0.5V
f=120Hz (sine wave)
RIN=2kΩ
e
i(rms)=0.5V (sine wave)
R1
2
=0.5kΩ
RR=20 log(ei(rms)/eo(rms)
)
0
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
0.1
1
10
100
Output current I (A)
O
Input ripple frequency f (kHz)
Fig.15 Ripple Rejection vs. Output Current
Fig.16 Circuit Operating Current vs. Input
Voltage (PQ20WZ51)
(PQ20WZ11)
80
20
Vc=2.7V,
R
1
=2kΩ, R
2
=500Ω
75
70
65
60
55
(Vo=3.3V)
15
10
RL =6.6Ω
RL
=11Ω
T
=25˚C
Vj =5V
RIN=2kΩ
50
45
40
5
0
R1=0.5kΩ
ei2(rms)=0.5V
RL
=∞Ω
f=120Hz (sine wave)
0
1
2
3
4
5
6
0
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
Output current I
O
(A)
Input voltage VIN (V)
SHARP [ SHARP ELECTRIONIC COMPONENTS ]
