The MIC5156, MIC5157, and MIC5158 Super Low-Dropout (LDO) Regulator Controllers are single IC solutions for highcurrent low-dropout linear voltage regulation. Super LDO?
Regulators have the advantages of an external N-channel power MOSFET as the linear pass element.The MIC5156/7/8 family features a dropout voltage as low as the RDS(ON) of the external power MOSFET multiplied by the
output current. The output current can be as high as the
largest MOSFETs can provide.
The MIC5156/7/8 family operates from 3V to 36V. The
MIC5156 requires an external gate drive supply to provide the
higher voltage needed to drive the gate of the external
MOSFET. The MIC5157 and MIC5158 each have an internal
charge pump tripler to produce the gate drive voltage. The
tripler is capable of providing enough voltage to drive a logiclevel
MOSFET to 3.3V output from a 3.5V supply and is
clamped to 17.5V above the supply voltage. The tripler
requires three external capacitors.
The regulator output is constant-current limited when the
controller detects 35mV across an optional external sense
resistor. An active-low open-collector flag indicates a low
voltage of 8% or more below nominal output. A shutdown
(low) signal to the TTL-compatible enable control reduces
controller supply current to less than 1mA while forcing the
output voltage to ground.
The MIC5156-3.3 and MIC5156-5.0 controllers have internally
fixed output voltages. The MIC5156 [adjustable] output
is configured using two external resistors. The MIC5157 is a
fixed output controller which is externally configured to select either 3.3V, 5.0V, or 12V. The MIC5158 can be configured as a fixed 5V controller or programmed to any voltage from 1.3V to 36V using two external resistors.
The MIC5156 is available in an 8-pin DIP or SOP. The MIC5157 and MIC5158 are available in a 14-pin DIP or SOP which operate from –40°C to +85°C.