LT1575CN8-2.8#PBF

Overview

The LT1575CN8-2.8#PBF is a fixed-output low dropout regulator controller IC manufactured by Analog Devices Inc., housed in an 8-pin PDIP package. It provides a precision 2.8V output with ±0.6% tolerance at room temperature and ±1.0% over the operating temperature range. The device operates with an input voltage up to 20V, drawing a typical quiescent current of 12.5mA. It features a high-side current limit amplifier with a 50mV threshold and a multifunction shutdown pin for latchoff protection.

Feature Summary

• Ultrafast transient response capability that eliminates the need for bulky tantalum or electrolytic output capacitors
• High-side sense current limit amplifier with programmable time-out latchoff via the SHDN pin
• Precision-trimmed internal reference and feedback networks ensuring tight output voltage tolerance

Applications

• Microprocessor core power supplies requiring fast load step response
• Low voltage logic supply regulation
• GTL termination circuits

Procurement Notes

Verify the specific ordering suffix matches the required package type and output voltage configuration. Confirm RoHS compliance status through official manufacturer documentation prior to integration. Ensure the external N-channel MOSFET selected meets the gate drive requirements specified in the datasheet electrical characteristics.

Selection Notes

Select this component when ultrafast transient response is critical and bulk output capacitance must be minimized. The fixed 2.8V version simplifies design compared to adjustable variants by removing external feedback resistors. Ensure the external MOSFET RDS(ON) is chosen to achieve the desired dropout voltage performance under maximum load conditions.

Part Context

This part belongs to the LT1575/LT1577 family of single/dual controller ICs designed to drive external N-channel MOSFETs as source followers. The LT1575 variant provides a single regulator channel, whereas the LT1577 offers dual channels. These controllers are engineered for modern microprocessor applications demanding high bandwidth and precise voltage regulation without large output decoupling networks.

Replacement Considerations

LT1575CS8-2.8#PBF (SOIC Package)

FAQ

How does the LT1575CN8-2.8#PBF handle fault conditions?

The device utilizes a multifunction SHDN pin that activates a timer circuit upon current limit activation. If the fault persists, the comparator latches the gate drive off to protect the system.

What is the purpose of the INEG pin?

The INEG pin serves as the negative sense terminal for the high-side current limit amplifier. It connects to the low side of the external sense resistor to monitor drain current.