MC34268D

Overview

The MC34268D is a low-dropout linear voltage regulator manufactured by onsemi, designed for SCSI-2 applications. It provides a fixed output voltage of 2.85 V with a maximum output current capability of 800 mA. The device operates within an input voltage range from 4.25 V to 15 V and features a typical dropout voltage of 950 mV at 490 mA. It is housed in an 8-SOIC surface-mount package and supports operation temperatures from 0°C to +125°C.

Feature Summary

• Fixed 2.85 V output specifically optimized for SCSI-2 active termination requirements
• High current drive capability up to 800 mA for bus loading demands
• Low dropout performance ensures stable regulation under varying load conditions

Applications

• SCSI-2 active terminator circuits
• Data converter power supply conditioning
• Low noise analog reference stabilization

Procurement Notes

Verify component authenticity through authorized distribution channels due to the part's end-of-life status. Confirm RoHS compliance requirements as specific variants may differ. Validate package integrity upon receipt to ensure suitability for surface mount assembly processes. Review official datasheets for any recent product change notices affecting specifications or pinouts before final integration into designs.

Selection Notes

Select this regulator when a precise 2.85 V rail is required for legacy SCSI-2 interfaces. Ensure input voltage remains above the minimum threshold to maintain regulation. Consider thermal dissipation capabilities given the SOIC-8 package constraints at higher load currents. Verify that the fixed output architecture aligns with system design needs without requiring external feedback networks.

Part Context

The MC34268 belongs to a family of specialized low-dropout regulators tailored for SCSI bus termination. It serves as a critical power management component in older computer peripheral interfaces. The D suffix denotes the 8-SOIC surface-mount package variant. This component bridges power delivery and signal integrity requirements in high-speed data transmission environments.

Replacement Considerations

Public confirmed substitute part numbers are not available.