Datasheet
Package Availability, Models, Samples & Pricing
General Description
The LM34917A Step-Down Switching Regulator features all the functions needed to implement a low cost, efficient, buck bias
regulator capable of supplying at least 1.25A to the load. To reduce excessive switch current due to the possibility of a
saturating inductor the valley current limit threshold changes with input and output voltages, and the on-time is reduced
when current limit is detected. This buck regulator contains an N-Channel Buck Switch, and is available in the 12 pin micro
SMD package. The constant on-time feedback regulation scheme requires no loop compensation, results in fast load transient
response, and simplifies circuit implementation. The operating frequency remains constant with line and load variations due
to the inverse relationship between the input voltage and the on-time. The valley current limit results in a smooth transition
from constant voltage to constant current mode when current limit is detected, reducing the frequency and output voltage,
without the use of foldback. Additional features include: VCC under-voltage lock-out, input over-voltage shutdown, thermal shutdown, gate drive under-voltage lock-out, and maximum duty
cycle limit.
Application Notes
| Title | Size in Kbytes |
Date |
 |
| AN-1601: Application Note 1601 LM34917A Evaluation Board |
1142 Kbytes |
10-Apr-08 |
Download |
[Information as of 13-Oct-2008]
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