CDCU877BZQLR Equivalent & Substitute Parts

Part Overview

The CDCU877BZQLR is a Memory DDR2 Clock Buffer/Driver IC manufactured by Texas Instruments, designed for high-speed clock distribution in DDR2 memory applications. This 52-BGA device operates at up to 400MHz with 1.8V supply voltage and provides single output with 1:10 input-to-output ratio. The product is currently classified as Obsolete, making identification of compatible substitute parts essential for ongoing system support and new design implementations where legacy compatibility is required.

Substiute Parts

CDCU877BZQLR

Texas InstrumentsIn Stock: 1071CDCU877BZQLR Datasheet

Current PartRFQ

98ULPA877AHT

Renesas Electronics CorporationIn Stock: 83598ULPA877AHT Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the CDCU877BZQLR must satisfy the following core electrical and mechanical parameters to ensure functional compatibility:

Critical Matching Parameters:

• Main Purpose: Memory, DDR2 clock distribution
• Number of Circuits: 1 output
• Ratio - Input:Output: 1:10
• Voltage - Supply: 1.7V ~ 1.9V range
• Package / Case: 52-VFBGA form factor
• Differential Input/Output: Yes/Yes configuration
• Mounting Type: Surface Mount

Acceptable Variation Parameters:

• Frequency - Max: Must meet or exceed 400MHz minimum
• Operating Temperature: May differ based on application requirements
• Product Status: Active status preferred for new procurement
• RoHS/REACH Compliance: May vary by regional requirements

The 98ULPA877AHT from Renesas Electronics Corporation qualifies as a substitute based on matching all critical electrical specifications and package requirements, with enhanced frequency capability (410MHz) and active product status.

Parameter Comparison

Engineering Selection Recommendations

For Obsolete Part Replacement: The 98ULPA877AHT serves as the primary substitute for CDCU877BZQLR applications. Both devices maintain identical electrical specifications for DDR2 clock distribution, including 1:10 multiplexing ratio, 1.8V supply voltage operation, and 52-BGA package compatibility. The Renesas part offers improved frequency headroom at 410MHz versus 400MHz, providing additional margin for system timing requirements.

Compliance Considerations: The CDCU877BZQLR maintains ROHS3 compliance, while the 98ULPA877AHT is RoHS non-compliant. Organizations with mandatory RoHS requirements must evaluate regulatory applicability before substitution. Both parts maintain REACH Unaffected status.

Temperature Range Differences: The CDCU877BZQLR operates across -40°C to 85°C, while the 98ULPA877AHT operates 0°C to 70°C. Applications requiring extended low-temperature operation below 0°C must retain the original part or identify alternative solutions.

Moisture Sensitivity: The 98ULPA877AHT carries MSL 3 (168 Hours) versus MSL 2 (1 Year) for the original part, requiring stricter moisture control during storage and handling.

Frequently Asked Questions (FAQ)

Q: Can the 98ULPA877AHT directly replace CDCU877BZQLR in existing designs? A: Yes, for applications operating within 0°C to 70°C temperature range without RoHS compliance mandates. The electrical specifications, package form factor, and functional output characteristics are equivalent. Verify system temperature requirements and regulatory compliance status before implementation.

Q: What is the significance of the 1:10 input-to-output ratio? A: This ratio indicates the clock multiplexing function. The device accepts a single input clock and generates 10 output clock signals, essential for DDR2 memory controller applications requiring distributed clock distribution to multiple memory modules.

Q: Are the SSTL-18 input and output specifications compatible between both parts? A: The CDCU877BZQLR specifies SSTL-18 for both input and output. The 98ULPA877AHT specifies Clock input with SSTL-18 output. Both configurations support DDR2 memory signaling standards and are functionally compatible within the specified voltage and frequency parameters.

Q: What does the 52-BGA MICROSTAR JUNIOR (7x4.5) package designation mean? A: This describes a 52-pin Ball Grid Array package with MICROSTAR JUNIOR form factor measuring 7mm × 4.5mm. Both substitute parts use identical 52-VFBGA package geometry, ensuring PCB footprint compatibility.

Q: How does the 410MHz maximum frequency of the 98ULPA877AHT compare to the 400MHz specification of CDCU877BZQLR? A: The 10MHz additional frequency capability provides timing margin for high-speed DDR2 applications. Systems designed for 400MHz operation will function within the 98ULPA877AHT specifications with improved frequency headroom.

Q: What is the impact of MSL 3 (168 Hours) moisture sensitivity on the 98ULPA877AHT? A: MSL 3 requires component use within 168 hours of package opening under controlled humidity conditions. Compared to MSL 2 (1 Year), this requires more stringent moisture control during storage, handling, and assembly processes. Implement appropriate dry-pack storage and baking procedures per IPC standards.