Datasheet

MC34063A, MC33063A, NCV33063A
http://onsemi.com
7
1.25 V
Ref
Reg
V
out
5.0 V/500 mA
1.0 mH
V
out
+
100
Optional Filter
8
7
R
sc
0.33
6
V
in
25 V
100
+
R1 1.2 k
R2
3.6 k
SQ
R
Q2
Q1
I
pk
OSC
C
T
V
CC
+
−
Comp.
1
2
3
4
C
T
470
pF
470 C
O
+
5
L
1N5819
220 mH
Test Conditions Results
Line Regulation V
in
= 15 V to 25 V, I
O
= 500 mA 12 mV = ±0.12%
Load Regulation V
in
= 25 V, I
O
= 50 mA to 500 mA 3.0 mV = ±0.03%
Output Ripple V
in
= 25 V, I
O
= 500 mA 120 mVpp
Short Circuit Current
V
in
= 25 V, R
L
= 0.1 W
1.1 A
Efficiency V
in
= 25 V, I
O
= 500 mA 83.7%
Output Ripple With Optional Filter V
in
= 25 V, I
O
= 500 mA 40 mVpp
Figure 10. Step−Down Converter
11a. External NPN Switch 11b. External PNP Saturated Switch
8
7
6
R
sc
V
in
1
2
V
out
8
7
6
R
sc
V
in
1
2
V
Figure 11. External Current Boost Connections for I
C
Peak Greater than 1.5 A