LTC3631IMS8E#TRPBF Linear Technology, LTC3631IMS8E#TRPBF Datasheet - Page 9

• Manufacturer Part Number: LTC3631IMS8E#TRPBF
• Description: IC CONV STP-DWN SYNC ADJ 8-MSOP
• Manufacturer: Linear Technology
• Type: Step-Down (Buck)r

Specifications of LTC3631IMS8E#TRPBF

• Internal Switch(s): Yes
• Synchronous Rectifier: Yes
• Number Of Outputs: 1
• Voltage - Output: 0.8 ~ 45 V
• Current - Output: 100mA
• Voltage - Input: 4.5 ~ 45 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-MSOP Exposed Pad, 8-HMSOP, 8-eMSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -
• Frequency - Switching: -

operaTion
then the output voltage will be limited by the ramp rate
on the SS pin instead. The internal and external soft-start
functions are reset on start-up and after an undervoltage
or overvoltage event on the input supply.
In order to ensure a smooth start-up transition in any
application, the internal soft-start also ramps the peak
inductor current from 50mA during its 1ms ramp time to
the set peak current threshold. The external ramp on the
SS pin does not limit the peak inductor current during
start-up; however, placing a capacitor from the I
to ground does provide this capability.
Peak Inductor Current Programming
The offset of the peak current comparator nominally
provides a peak inductor current of 225mA. This peak
inductor current can be adjusted by placing a resistor
(Refer to Block Diagram)
SET
pin
from the I
of this pin through the resistor generates a voltage that is
translated into an offset in the peak current comparator,
which limits the peak inductor current.
Input Undervoltage and Overvoltage Lockout
The LTC3631 implements a protection feature which dis-
ables switching when the input voltage is not within the
4.5V to 45V operating range. If V
(4.35V maximum), an undervoltage detector disables
switching. Similarly, if V
minimum), an overvoltage detector disables switching.
When switching is disabled, the LTC3631 can safely sustain
input voltages up to the absolute maximum rating of 60V.
Switching is enabled when the input voltage returns to the
4.5V to 45V operating range.
SET
pin to ground. The 1µA current sourced out
IN
rises above 50V typical (47V
IN
falls below 4V typical
LTC3631
3631fc
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