LM2576H National Semiconductor, LM2576H Datasheet - Page 12

• Manufacturer Part Number: LM2576H
• Description: SIMPLE SWITCHER 3A Step-Down Voltage Regulator
• Manufacturer: National Semiconductor

www.national.com
LM2576 Series Buck Regulator Design Procedure
Given:
V
V
I
F = Switching Frequency (Fixed at 52 kHz)
1. Programming Output Voltage (Selecting R1 and R2,
as shown in Figure 2)
Use the following formula to select the appropriate resis-
tor values.
R
efficient and stability with time, use 1% metal film resis-
tors)
LOAD
PROCEDURE (Adjustable Output Voltage Versions)
OUT
IN
1
(Max) = Maximum Input Voltage
can be between 1k and 5k. (For best temperature co-
(Max) = Maximum Load Current
= Regulated Output Voltage
FIGURE 7. LM2576(HV)-ADJ
12
Given:
V
V
I
F = 52 kHz
1. Programming Output Voltage (Selecting R1 and R2)
R
LOAD
OUT
IN
2
EXAMPLE (Adjustable Output Voltage Versions)
(Max) = 25V
= 1k (8.13 − 1) = 7.13k, closest 1% value is 7.15k
(Max) = 3A
= 10V
(Continued)
DS011476-13