TC2574 Datasheet, PDF (20/25 Pages) TelCom Semiconductor, Inc – 0.5A Step-Down Switching Regulator

0.5A Step-Down Switching Regulator
TC2574
The TC2574–ADJ Step-Down Voltage Regulator with 5.0V @ 0.5A Output Power Capability.
Typical Application with Through-Hole PC Board Layout
Unregulated
DC Input
+Vin = 7.0 to 40 V
C1
22µF
+VIN
TC2574–ADJ
5
Feedback
1
Output
7
4 Pwr 2 Sig 3 ON/OFF
GND GND
L1
330µH
D1
1N5819
C2
220µF
L2
22µH
R2
6.12 kW
R1
2.0 kW
C3
100µF
Regulated
Output Filtered
VOUT _{= 5.0 V @ 0.5 A}
GND
GND
C1 – 22µF, 63V, Aluminum Electrolytic
C2 – 220µF, 16V, Aluminum Electrolytic
C3 – 100µF, 16V Aluminum Electrolytic
D1 – 1.0A, 40V, Schotty Rectifier, 1N5829
L1 – 330µH, RL–1284–330, Renco Electronics
L2 – 25µH, SFT52501, TDK
R1 – 2.0kΩ, 0.1%, 0.25W
R2 – 6.12kΩ, 0.1%, 0.25W
Output
Ripple Filter
Figure 20. Schematic Diagram of the 5.0V @ 0.5A Step-Down Converter Using the TC2574–ADJ
(An additional LC filter is included to achieve low output ripple voltage)
+
+VIN
C1
GND
TC2574
U1
D1
R1 R2
L1
C2
+
C3
+
GND
L2
VOUT
NOTE: Not to scale.
Figure 21. PC Board Layout Component Side
NOTE: Not to scale.
Figure 22. PC Board Layout Copper Side
TC2574-1 1/6/00
20