Datasheet Analog Devices LT3668 — 数据表

LT3668
40V 400mA Step-Down
Switching Regulator with Dual
Fault Protected Tracking LDOs
DESCRIPTION FEATURES Dual Low Dropout Linear Tracking Regulators
nn 200mA Outputs with Programmable Current Limits
nn 1.6V to 45V Input Range
nn Fault Protected to ±45V
nn Triple Output Supply from a Single Input Requires
Only One Inductor
nn I = 50μA at 12V to 6V and 5V with No Load
Q
IN
nn Buck Regulator:
®
nn Low Ripple ( VOVLO (overvoltage lockout, 42V typical), allowing the output to fall out of regulation. 14 During start-up, short-circuit, or other overload conditions
the inductor peak current might reach and even exceed the
maximum current limit of the LT3668, especially in those
cases where the switch already operates at minimum ontime. The catch diode current limit circuitry prevents the
switch from turning on again if the inductor valley current
is above 500mA nominal.
Inductor Selection and Maximum Output Current
For a given input and output voltage, the inductor value …