LM3477MM National Semiconductor, LM3477MM Datasheet - Page 2

• Manufacturer Part Number: LM3477MM
• Description: Pulse Width Modulation (PWM) Controller IC
• Manufacturer: National Semiconductor

Specifications of LM3477MM

• Input Voltage Primary Min: 2.95V
• Mounting Type: Surface Mount
• Topology: Buck (Step Down)
• Control Mode: Current
• Duty Cycle Max: 93%
• Input Voltage Primary Max: 35V
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

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Connection Diagram
Package Marking and Ordering Information
Pin Description
COMP/SD
Pin Name
GND
I
SW
DR
V
SEN
FB
CB
Order Number
LM3477AMMX
IN
LM3477MMX
LM3477AMM
LM3477MM
Pin Number
1
2
3
4
5
6
7
8
Package Type
MSOP-8
MSOP-8
MSOP-8
MSOP-8
8 Lead Mini SO8 Package (MSOP-8 Package)
Current sense input pin. Voltage generated across an external sense resistor is fed
into this pin.
Compensation pin. A resistor-capacitor combination connected to this pin provides
compensation for the control loop. Pull this pin below 0.65V to shutdown.
Feedback pin. The output voltage should be adjusted using a resistor divider to
provide 1.270V at this pin.
Ground pin.
Switch Node. Source of the external MOSFET is connected to this node.
Drive pin. The gate of the external MOSFET should be connected to this pin.
Boot-strap pin. A capacitor must be connected between this pin and SW pin (pin 5)
for proper operation. The voltage developed across this capacitor provides the gate
drive for the external MOSFET.
Power Supply Input pin.
Package Marking
2
S13B
S13B
S13A
S13A
Description
20003302
1000 units on Tape and Reel
3500 units on Tape and Reel
1000 units on Tape and Reel
3500 units on Tape and Reel
Supplied As: