LM3485MM National Semiconductor, LM3485MM Datasheet - Page 15

• Manufacturer Part Number: LM3485MM
• Description: Pulse Width Modulation (PWM) Controller IC
• Manufacturer: National Semiconductor

Specifications of LM3485MM

• Input Voltage Primary Min: 4.5V
• Mounting Type: Surface Mount
• Topology: Buck (Step Down)
• Control Mode: Hysteretic
• Duty Cycle Max: 100%
• Input Voltage Primary Max: 35V
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

PCB Layout
C1: C
C2: C
C3: C
C4: C
D1: 1A/40V MBRS140T3 (On Semiconductor)
L1: 22µH :QH66SN220M01L (Murata)
Q1: FDC5614P (Fairchild)
R1: 33K
R2: 20K
R3: R
IN
OUT
ADJ
FF
ADJ
22µF/35V EEJL1VD226R (Panasonic)
100pF Ceramic Chip Capacitor
1nF Ceramic Chip Capacitor
24K
100µF/6.3V 6TPC100M (Sanyo)
Chip Resistor
Chip Resistor
Chip Resistor
(Continued)
Top Layer
FIGURE 7. Typical PCB Layout (3.3V Output)
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Silk Screen
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Bottom Layer
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