The LP3891 is a high current, fast response regulator which can maintain output voltage
regulation with minimum input to output voltage drop. Fabricated on a CMOS process, the device
operates from two input voltages: Vbias provides voltage to drive the gate of the N-MOS power
transistor, while Vin is the input voltage which supplies power to the load. The use of an external
bias rail allows the part to operate from ultra low Vin voltages. Unlike bipolar regulators, the
CMOS architecture consumes extremely low quiescent current at any output load current. The use of
an N-MOS power transistor results in wide bandwidth, yet minimum external capacitance is required
to maintain loop stability.
The fast transient response of these devices makes them suitable for use in powering DSP,
Microcontroller Core voltages and Switch Mode Power Supply post regulators. The parts are available
in TO-220, DDPAK/TO-263 and SO PowerPAD-8 packages.
Dropout Voltage: 100 mV (typ) at 0.8A load
current.
Ground Pin Current: 3 mA (typ) at full load.
Shutdown Current: 60 nA (typ) when S/D pin is
low.
Precision Output Voltage: 1.5% room temperature
accuracy.
The LP3891 is a high current, fast response regulator which can maintain output voltage
regulation with minimum input to output voltage drop. Fabricated on a CMOS process, the device
operates from two input voltages: Vbias provides voltage to drive the gate of the N-MOS power
transistor, while Vin is the input voltage which supplies power to the load. The use of an external
bias rail allows the part to operate from ultra low Vin voltages. Unlike bipolar regulators, the
CMOS architecture consumes extremely low quiescent current at any output load current. The use of
an N-MOS power transistor results in wide bandwidth, yet minimum external capacitance is required
to maintain loop stability.
The fast transient response of these devices makes them suitable for use in powering DSP,
Microcontroller Core voltages and Switch Mode Power Supply post regulators. The parts are available
in TO-220, DDPAK/TO-263 and SO PowerPAD-8 packages.
Dropout Voltage: 100 mV (typ) at 0.8A load
current.
Ground Pin Current: 3 mA (typ) at full load.
Shutdown Current: 60 nA (typ) when S/D pin is
low.
Precision Output Voltage: 1.5% room temperature
accuracy.