LTC4371
Dual Negative Voltage
Ideal Diode-OR Controller
and Monitor
Description Features
Controls N-Channel MOSFETs to Replace Power
Schottky Diodes
nn Low 15mV Forward Voltage Minimizes Dissipation
nn Withstands > В±300V Transients
nn Fast Turn-Off: В 5mA, no VDD bypassing is required.
Note that a shorted gate will demand a continuous current
of 5mA whenever ∆VSD is large. The LTC4371 attempts to servo the forward drop across
the MOSFET (∆VSD) to 15mV by controlling the gate, and
flags a fault if the drop exceeds 200mV when the MOSFET is
driven fully on. Thus an upper bound for RDS(ON) is set by: The 5mA pull-up is enabled when VZ is biased to >11.8V
in its normal shunt regulator mode, or when VZ is В 250V
Applications with 5mA Gate Pull-Up Current Disabled MOSFET Selection
The LTC4371 drives N-channel MOSFETs to conduct the
load current. The important features of the MOSFETs are
threshold voltage, VGS(TH); maximum drain-source voltage,
BVDSS; and on-resistance, RDS(ON).
Full gate drive for the MOSFETs (∆V GATE ) is
VDDВ +В 100mV/–200mV. When used in shunt regulated …
