Datasheet Analog Devices LT3689-5 — Datenblatt

LT3689/LT3689-5
700mA Step-Down
Regulator with Power-On Reset
and Watchdog Timer
DESCRIPTION FEATURES Wide Input Range: Operation from 3.6V to 36V Overvoltage Lockout Protects Circuits through 60V Transients
n 85µA I at 12V to 3.3V
Q
IN
OUT
n Low Ripple Burst Mode® Operation Allows Output
Ripple 38V (typical),
the LT3689 will stop switching, allowing the output to fall
out of regulation. DCMIN = tON(MIN) • fSW
where tON(MIN) is equal to 130ns (for TJ > 125°C tON(MIN)
is equal to 150ns) and fSW is the switching frequency.
Running at a lower switching frequency allows a lower
minimum duty cycle. The maximum input voltage before
pulse-skipping occurs depends on the output voltage and
the minimum duty cycle: VIN(PS) = VOUT + VD
– VD + VSW
DCMIN Minimum Operating Voltage Range
The minimum input voltage is determined either by the
LT3689’s minimum operating voltage of ~3.4V or by its …