RT9173BGS

Overview

The RT9173BGS is a high-speed linear regulator designed for DDR memory termination. It actively sinks or sources up to 2A while regulating output voltage within 40mV accuracy. The device supports SSTL_2, SSTL_18, HSTL, SCSI-2, and SCSI-3 interfaces. It features integrated power MOSFETs, thermal protection, and current limiting. Input voltage range is typically 2.5V to 5.5V. Output voltage is adjustable via external resistors or REFEN pin forcing.

Feature Summary

• Active sink and source capability for precise termination voltage regulation
• Integrated power MOSFETs reduce external component count
• Thermal shutdown and current limiting protection mechanisms
• High impedance output state for suspend-to-RAM functionality

Applications

• DDR-I, DDR-II, and DDR-III memory system termination
• Desktop PCs, notebooks, and workstations
• Graphics card memory termination circuits
• Set-top boxes and digital TVs

Procurement Notes

Verify the specific suffix 'BGS' against official Richtek datasheets to confirm package type and tape/reel specifications. Confirm RoHS compliance status and lead-free certification with the manufacturer. Check for any recent Product Change Notices (PCN) regarding manufacturing site changes or material updates before finalizing procurement orders.

Selection Notes

Select this component when designing DDR memory termination circuits requiring bidirectional current handling. Ensure the input voltage range matches the system's VDDQ or VDDSPD levels. Verify that the thermal performance in the target application environment stays within junction temperature limits under maximum load conditions. Consider external resistor precision for output voltage accuracy requirements.

Part Context

The RT9173 series addresses termination voltage needs in double data rate memory systems. It complies with JEDEC SSTL_2, SSTL_18, HSTL, SCSI-2, and SCSI-3 interface standards. The regulator tracks 1/2VDDQ or allows programmable output via the REFEN pin. It eliminates power sequence issues between VIN and VCNTL pins, simplifying system design for embedded applications and active termination buses.

Replacement Considerations

RT9173CS is listed as a similar part number with comparable 1.5A/3A bus termination capabilities. Verify electrical parameters and pin compatibility before substitution. No direct public substitute part numbers are confirmed for the RT9173BGS variant specifically.