MIC5156-3.3BM

Overview

The MIC5156-3.3BM is a Super LDO Regulator Controller in an 8-pin SOIC package, designed for high-current linear voltage regulation using an external N-channel MOSFET. It provides a fixed 3.3V output with a supply voltage range of 3V to 36V and operates within a temperature range of -40°C to +85°C. The device features a typical operating current of 4.5mA and less than 1µA standby current. It includes optional current limiting with a 35mV threshold, an open-collector flag for out-of-regulation detection, and an enable pin for shutdown control.

Feature Summary

• Fixed 3.3V output configuration
• External gate drive supply requirement
• Optional constant-current limiting
• Open-collector fault flag output

Applications

• Ultrahigh current ultralow dropout voltage regulator
• Constant high-current source
• Low parts count 5.0V to 3.3V computer supply
• High-current, current-limited switch

Procurement Notes

Verify the specific suffix 'BM' confirms the 8-pin SOIC package and industrial temperature rating (-40°C to +85°C). Confirm that the component requires an external gate drive supply voltage (VP) as it lacks an internal charge pump. Ensure the application circuit includes the necessary external N-channel MOSFET and sense resistor for current limiting functionality.

Selection Notes

Select this controller when a fixed 3.3V output is required without the need for an internal charge pump. It is suitable for applications where an external gate drive supply is already available or can be easily generated. Consider alternative models like the MIC5157 if an internal charge pump is preferred to simplify the gate drive design.

Part Context

This component belongs to the MIC5156/5157/5158 family of Super LDO Regulator Controllers. Unlike the MIC5157 and MIC5158, which feature internal charge pumps for gate drive, the MIC5156 relies on an external VP pin for driving the external MOSFET gate. It is one of the smallest controllers in the family, offering a compact solution for fixed voltage regulation.

Replacement Considerations

MIC5156-3.3BN (DIP package)

FAQ

Does the MIC5156-3.3BM have an internal charge pump?

No, the MIC5156 requires an external gate drive supply voltage applied to the VP pin to drive the external MOSFET.

How is current limiting implemented?

Current limiting is implemented by placing a sense resistor between VDD and the Drain pin. If the voltage drop across the resistor reaches 35mV, the controller reduces the error amplifier output to limit the current.