LM2674LDX-3.3 National Semiconductor, LM2674LDX-3.3 Datasheet - Page 21

• Manufacturer Part Number: LM2674LDX-3.3
• Manufacturer: National Semiconductor

Specifications of LM2674LDX-3.3

• Dc To Dc Converter Type: Step Down
• Number Of Outputs: 1
• Pin Count: 16
• Input Voltage: 40V
• Output Voltage: 3.3V
• Switching Freq: 275KHz
• Output Current: 500mA
• Efficiency: 86%
• Package Type: LLP EP
• Output Type: Fixed
• Switching Regulator: Yes
• Mounting: Surface Mount
• Input Voltage (min): 8V
• Operating Temp Range: -40C to 125C
• Operating Temperature Classification: Automotive
• Lead Free Status / Rohs Status: Not Compliant

LM2674 Series Buck Regulator Design Procedure (Adjustable Output)
Note 8: The SC series of Os-Con capacitors (others are SA series)
Note 9: The voltage ratings of the surface mount tantalum chip and Os-Con capacitors are too low to work at these voltages.
(Continued)
Desg.
Cap.
Ref.
C10
C11
C12
C13
C14
C15
C16
C17
C18
C19
C20
C21
C22
C23
C24
C25
C1
C2
C3
C4
C5
C6
C7
C8
C9
#
594D Series
Sprague
(Note 9)
(Note 9)
(Note 9)
120/6.3
120/6.3
120/6.3
100/16
100/16
100/16
100/16
100/16
100/16
100/16
100/16
100/16
(µF/V)
68/10
68/10
47/20
47/20
47/20
68/25
33/25
33/25
33/35
33/35
Surface Mount
(2x) 33/25
(2x) 22/25
AVX TPS
(Note 9)
(Note 9)
(Note 9)
Series
100/10
100/10
100/10
100/10
100/10
100/10
100/10
100/10
100/16
100/16
100/16
100/16
100/16
100/16
(µF/V)
68/20
68/20
68/20
33/25
33/25
22/35
FIGURE 17. Output Capacitor Selection Table
Sanyo OS-CON
47/25 (Note 8)
33/25 (Note 8)
33/25 (Note 8)
Output Capacitor
SA Series
(Note 9)
(Note 9)
(Note 9)
(Note 9)
(Note 9)
100/10
100/10
100/35
100/10
100/10
100/10
100/16
100/16
100/16
(µF/V)
68/10
68/10
68/16
68/16
68/16
47/20
47/20
47/20
21
Sanyo MV-GX
Series
220/35
150/35
120/35
220/35
150/35
120/35
150/35
330/35
330/35
220/35
150/35
120/35
120/35
220/35
220/35
150/35
120/35
220/35
150/35
120/35
150/35
120/35
220/50
150/50
150/50
(µF/V)
Through Hole
PL Series
Nichicon
220/35
150/35
120/35
220/35
150/35
120/35
150/35
330/35
330/35
220/35
150/35
120/35
120/35
220/35
220/35
150/35
120/35
220/35
150/35
120/35
150/35
120/35
100/50
100/50
(µF/V)
82/50
HFQ Series
Panasonic
220/35
150/35
120/35
220/35
150/35
120/35
150/35
330/35
330/35
220/35
150/35
120/35
120/35
220/35
220/35
150/35
120/35
220/35
150/35
120/35
150/35
120/35
120/50
120/50
(µF/V)
82/50
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