Datasheet Analog Devices LT8608IDC#PBF — 数据表

LT8608/LT8608B
42V, 1.5A Synchronous Step-Down Regulator
with 2.5µA Quiescent Current
FEATURES DESCRIPTION Wide Input Voltage Range: 3.0V to 42V
nn Ultralow Quiescent Current Burst Mode® Operation:
nn 0.5),
a minimum inductance is required to avoid sub-harmonic
oscillation. See Application Note 19.
Input Capacitor where ∆IL is the inductor ripple current as calculated
several paragraphs below and ILOAD(MAX) is the maximum
output load for a given application. The peak-to-peak ripple current in the inductor can be
calculated as follows: Bypass the input of the LT8608 circuit with a ceramic capacitor of X7R or X5R type. Y5V types have poor performance
over temperature and applied voltage, and should not be
used. A 4.7μF to 10μF ceramic capacitor is adequate to
bypass the LT8608 and will easily handle the ripple current.
Note that larger input capacitance is required when a lower
switching frequency is used. If the input power source has
high impedance, or there is significant inductance due to
long wires or cables, additional bulk capacitance may be
necessary. This can be provided with a low performance
electrolytic capacitor.
Step-down regulators draw current from the input supply in pulses with very fast rise and fall times. The input
capacitor is required to reduce the resulting voltage …