The MIC5156, MIC5157, and MIC5158 Super Low-Dropout (LDO) Regulator Controllers are single IC solutions for high-current 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 MIC5156-3.3BM 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 logic-level 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 1µA while forcing the output voltage to ground.
The MIC5156-3.3 and MIC5156-5.0 controllers have internally fixed output voltages. The MIC5156-3.3BM [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 MIC5156-3.3BM 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.
Feature
- 4.5mA typical operating current
- <1µA typical standby current
- Low externalparts count
- Optional current limit (35mV typical threshold)
- 1% initial output voltage tolerance in most configurations
- 2% output voltage tolerance over temperature
- Fixed output voltages of 3.3V, 5.0V (MIC5156)
- Programmable (1.3V to 36V) with 2 resistors (MIC5156/8)
- Enable pin to activate or shutdown the regulator
- Internal gate-to-source protective clamp
- All versions available in DIP and SOIC