LM3478_09 Datasheet, PDF (2/22 Pages) National Semiconductor (TI) – High Efficiency Low-Side N-Channel Controller for Switching Regulator

Connection Diagram
10135502
8 Lead Mini SO8 Package (MSOP-8 Package)
Package Marking and Ordering Information
Order Number
LM3478MM
LM3478MMX
LM3478QMM
LM3478QMMX
Package Type Package Marking
MSOP-8
S14B
MSOP-8
SSFB
Supplied As:
1000 units on Tape and Reel
3500 units on Tape and Reel
1000 units on Tape and Reel
3500 units on Tape and Reel
Feature
AEC-Q100 (Grade 1) qualified.
Automotive Grade Production Flow*
* Automotive Grade (Q) product incorporates enhanced manufacturing and support processes for the automotive market, including defect detection methodologies.
Reliability qualification is compliant with the requirements and temperature grades defined in the AEC-Q100 standard. Automotive grade products are identified
with the letter Q. For more information go to http://www.national.com/automotive.
Pin Descriptions
Pin Name
I_SEN
COMP
FB
AGND
PGND
DR
FA/SD
V_IN
Pin Number
1
2
3
4
5
6
7
8
Description
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.
Feedback pin. The output voltage should be adjusted using a resistor
divider to provide 1.26V at this pin.
Analog ground pin.
Power ground pin.
Drive pin. The gate of the external MOSFET should be connected to
this pin.
Frequency adjust and Shutdown pin. A resistor connected to this pin
sets the oscillator frequency. A high level on this pin for longer than
30 µs will turn the device off. The device will then draw less than 10µA
from the supply.
Power Supply Input pin.
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