Chopper Regulators
Fig.10 Oscillation Frequency Fluctuation vs.
Junction Temperature
5
PQ1CG2032FZ/PQ1CG2032RZ
Fig.11 Overcurrent Detecting Level
Fluctuation vs. Junction Temperature
6
Overcurrent detecting level fluctuation (%)
125
Oscillation frequency fluctuation (%)
4
2
0
−2
−4
−6
−8
−25
0
−5
V
IN
=12V
V
O
=5V
−10
−25
0
25
50
75
100
0
25
50
75
100
125
Junction temperature T
j
(°C)
Junction temperature T
j
(°C)
Fig.12 Threshold Voltage vs. Junction
Temperature
Threshold voltage V
TH (ON) ,
V
TH (L) ,
V
TH (H)
(V)
Fig.13 Operating Dissipation Current vs.
Input Voltage
10
Operating dissipation current I
Q'
(mA)
3
V
TH(H)
2.5
V
IN
=12V
Tj=25°C
V
O
=5V
9
I
O
=1A
8
2
V
TH(L)
1.5
7
I
O
=3A
6
No load
5
1
0.5
0
−25
V
TH(ON)
0
25
50
75
100
125
0
10
20
Input voltage V
IN
(V)
30
40
Junction temperature T
j
(°C)
Fig.14 Block Diagram
1
V
IN
2
V
OUT
Voltage
regulator
ON/OFF
circuit
5
PWM COMP.
_
Soft start
ON/OFF
+
Overcurrent
detection
circuit
F/F
Q
R
S
Oscillator
_
+
ERROR AMP.
V
ref
4
O
ADJ
Overheat
detection
circuit
3
COM
SHARP [ SHARP ELECTRIONIC COMPONENTS ]
