ASCSM-25.000MHZ-LR-T Equivalent & Substitute Parts

Part Overview

The ASCSM-25.000MHZ-LR-T is a 25 MHz MEMS-based XO (Standard) oscillator manufactured by Abracon LLC, designed for applications requiring a CMOS output with enable/disable functionality. This part operates across a wide supply voltage range of 1.7V to 3.6V and is housed in a compact 4-UFBGA/CSPBGA package measuring 1.79mm × 1.25mm. The product is currently obsolete, making identification of suitable substitute components essential for ongoing system support and new design implementations.

Substiute Parts

ASCSM-25.000MHZ-LR-T

Abracon LLCIn Stock: 950ASCSM-25.000MHZ-LR-T Datasheet

Current PartRFQ

ASCO-25.000MHZ-L-T3

Abracon LLCIn Stock: 1156ASCO-25.000MHZ-L-T3 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the ASCSM-25.000MHZ-LR-T is determined by the following critical parameters:

Mandatory Matching Parameters:

• Frequency: 25 MHz (exact match required)
• Output Type: CMOS
• Function: Enable/Disable capability
• Operating Temperature Range: -40°C ~ 85°C (minimum requirement)
• Mounting Type: Surface Mount
• RoHS Compliance: ROHS3 Compliant

Allowable Variation Parameters:

• Base Resonator: MEMS or Crystal (both acceptable for frequency generation)
• Voltage Supply Range: Substitute must support the application's operating voltage; the main part's 1.7V ~ 3.6V range is wider than the substitute's 3.3V specification
• Frequency Stability: Substitute tolerance of ±50ppm is broader than the main part's ±25ppm; acceptable if application requirements permit
• Package / Case: Different SMD packages acceptable if footprint compatibility is verified
• Current Supply (Max): Substitute specification of 6mA is within acceptable range relative to main part's 6.5mA
• Physical Dimensions: Minor variations acceptable within PCB layout constraints

The ASCO-25.000MHZ-L-T3 meets all mandatory matching parameters and represents a valid substitute for the obsolete ASCSM-25.000MHZ-LR-T.

Parameter Comparison

Engineering Selection Recommendations

The ASCO-25.000MHZ-L-T3 is qualified as a substitute for the obsolete ASCSM-25.000MHZ-LR-T based on the following engineering criteria:

Product Status Alignment: The substitute part maintains Active status with Abracon LLC, ensuring continued availability and manufacturing support. The main part's Obsolete designation necessitates transition to an alternative component.

Compliance Certification: Both parts maintain ROHS3 Compliance and REACH Unaffected status, satisfying regulatory requirements for equivalent environmental and hazardous substance standards.

Functional Equivalence: Identical frequency (25 MHz), output type (CMOS), and enable/disable function ensure direct functional compatibility in applications designed for the main part.

Electrical Compatibility: The substitute operates at 3.3V, which falls within the main part's 1.7V ~ 3.6V supply range. Applications operating at 3.3V supply voltage will experience no functional degradation. Applications requiring operation below 3.3V require design review.

Frequency Stability Consideration: The substitute's ±50ppm stability specification is broader than the main part's ±25ppm. Applications with frequency stability requirements tighter than ±50ppm require evaluation against actual system specifications.

Package and Footprint: The substitute uses 4-SMD No Lead packaging versus the main part's 4-UFBGA/CSPBGA. Physical dimensions are comparable (1.60mm × 1.20mm versus 1.79mm × 1.25mm), and height specifications are equivalent (0.70mm versus 0.69mm). PCB layout verification is required to confirm footprint compatibility.

Frequently Asked Questions (FAQ)

Q: Can the ASCO-25.000MHZ-L-T3 directly replace the ASCSM-25.000MHZ-LR-T without design modifications?

A: Direct replacement is possible if the application operates at 3.3V supply voltage and accepts ±50ppm frequency stability. The 4-SMD No Lead package differs from the original 4-UFBGA/CSPBGA package, requiring PCB footprint verification and potential layout adjustments.

Q: What is the primary difference between the main part and the substitute?

A: The main part uses MEMS resonator technology with a wider supply voltage range (1.7V ~ 3.6V) and tighter frequency stability (±25ppm). The substitute uses crystal resonator technology, operates at fixed 3.3V, and has broader frequency stability (±50ppm). Both deliver identical 25 MHz CMOS output with enable/disable functionality.

Q: Is the substitute suitable for low-voltage applications below 3.3V?

A: No. The ASCO-25.000MHZ-L-T3 is specified for 3.3V operation only. Applications requiring operation at 1.7V to 3.0V require alternative components or design reconsideration.

Q: How do the package differences affect PCB design?

A: The substitute's 4-SMD No Lead package has slightly smaller footprint dimensions (1.60mm × 1.20mm) compared to the main part (1.79mm × 1.25mm). Height specifications are nearly identical (0.70mm versus 0.69mm). Existing PCB layouts designed for 4-UFBGA/CSPBGA packages require footprint redesign and revalidation.

Q: Are there any compliance or regulatory concerns with substitution?

A: No. Both parts maintain ROHS3 Compliance and REACH Unaffected status. Substitution does not introduce regulatory compliance issues.

Q: What should be evaluated before implementing this substitute in production?

A: Verify supply voltage compatibility at 3.3V, confirm frequency stability requirements do not exceed ±50ppm, validate PCB footprint and layout compatibility with the 4-SMD No Lead package, and perform functional testing in the target application environment.