lm2574dw ON Semiconductor, lm2574dw Datasheet - Page 21

• Manufacturer Part Number: lm2574dw
• Description: 0.5 A, Adjustable Output Voltage, Stepdown Switching Regulator
• Manufacturer: ON Semiconductor

NOTE: This picture does not show the complete circuit (see Figure 27).
1N5242
40 V Max
Unregulated
DC Input
+V
Figure 34. Undervoltage Lockout Circuit for
15 k
15 k
R2
Z1
R1
in
22 mF
C
in
68 k
R3
+V
Buck−Boost Converter
in
5
Q1
2N3904
Figure 35. 1.2 to 35 V Adjustable 500 mA Power Supply with Low Output Ripple
4
(12)
Pwr
Gnd
LM2574−ADJ
(6)
C
22 mF
+V
in
2
in
5
Sig
Gnd
(4)
(12)
3
LM2574−XX
3
ON/OFF
(14)
(5)
(3)
ON/OFF
(5)
7
1
Feedback
Output
and
2
4
Gnds
Pins
LM2574, NCV2574
−V
http://onsemi.com
D1
1N5819
and
(4)
(6)
out
150 mH
L1
21
Adjustable Output, Low−Ripple Power Supply
features an adjustable output voltage is shown in Figure 35.
input voltage ranges from roughly 3.0 to 40 V. In order to
achieve a 10 or more times reduction of output ripple, an
additional L−C filter is included in this circuit.
C
1000 mF
A 0.5 A output current capability power supply that
This regulator delivers 0.5 A into 1.2 to 35 V output. The
out
R2
50 k
R1
1.1 k
Optional Output
Ripple Filter
20 mH
100 mF
L2
C1
1.2 to 35 V @ 0.5 A
Voltage
Output