ASCSM-18.432MHZ-LR-T Equivalent & Substitute Parts

Part Overview

The ASCSM-18.432MHZ-LR-T is a 18.432 MHz MEMS-based XO (Standard) oscillator manufactured by Abracon LLC, designed for applications requiring a precision frequency reference with wide supply voltage range (1.7V ~ 3.6V). This component features CMOS output, Enable/Disable functionality, and is housed in a compact 4-UFBGA/CSPBGA package measuring 1.79mm × 1.25mm.

The ASCSM-18.432MHZ-LR-T has reached obsolete product status. Identifying suitable substitute components is necessary to maintain design continuity and ensure continued availability for production and field replacement applications.

Substiute Parts

ASCSM-18.432MHZ-LR-T

Abracon LLCIn Stock: 757ASCSM-18.432MHZ-LR-T Datasheet

Current PartRFQ

ASCO-18.432MHZ-L-T3

Abracon LLCIn Stock: 960ASCO-18.432MHZ-L-T3 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the ASCSM-18.432MHZ-LR-T is determined by the following critical parameters:

• Frequency Match: 18.432 MHz (exact match required)
• Output Type: CMOS (exact match required)
• Operating Temperature Range: -40°C ~ 85°C (minimum requirement)
• Enable/Disable Function: Required
• Package Compatibility: Surface mount form factor with compatible pinout
• Supply Voltage Compatibility: Substitute must operate within or encompass the original 1.7V ~ 3.6V range
• Frequency Stability: Substitute stability must meet or exceed ±25ppm specification
• RoHS Compliance: ROHS3 Compliant status required

The ASCO-18.432MHZ-L-T3 qualifies as a direct substitute based on matching frequency, CMOS output, Enable/Disable functionality, operating temperature range, and RoHS compliance. However, critical differences exist in supply voltage range, frequency stability, and resonator technology that must be evaluated for specific application requirements.

Parameter Comparison

Engineering Selection Recommendations

The ASCO-18.432MHZ-L-T3 is an active product with confirmed availability (874 Pcs in stock), providing supply continuity for the obsolete ASCSM-18.432MHZ-LR-T. Both components are ROHS3 compliant and manufactured by the same supplier, ensuring regulatory alignment.

Selection of the ASCO-18.432MHZ-L-T3 requires verification of the following application-specific constraints:

• Supply Voltage: The substitute operates at fixed 3.3V, whereas the original supports 1.7V ~ 3.6V. Applications requiring operation below 3.0V or above 3.6V cannot use this substitute.
• Frequency Stability: The substitute exhibits ±50ppm stability compared to the original ±25ppm. Applications with tight frequency tolerance requirements must evaluate whether the degraded stability is acceptable.
• Resonator Technology: The substitute uses crystal-based resonance versus MEMS in the original. This affects long-term aging characteristics and environmental sensitivity.
• Package Form Factor: The substitute uses 4-SMD No Lead packaging versus 4-UFBGA/CSPBGA. PCB layout and assembly process compatibility must be confirmed.
• Current Consumption: The substitute draws 4.5mA maximum versus 6.5mA, providing improved power efficiency.

Frequently Asked Questions (FAQ)

Q: Can the ASCO-18.432MHZ-L-T3 be used as a direct pin-for-pin replacement?

A: No. While both components provide 18.432 MHz CMOS output with Enable/Disable functionality, the package types differ (4-UFBGA/CSPBGA versus 4-SMD No Lead). PCB layout modifications and potential assembly process changes are required. Pinout compatibility must be verified against the specific application schematic.

Q: What is the impact of the frequency stability difference (±25ppm vs ±50ppm)?

A: Frequency stability determines the maximum deviation from the nominal 18.432 MHz frequency across operating conditions. The original ±25ppm specification provides tighter tolerance. Applications sensitive to frequency drift, such as precision timing or communication protocols with narrow bandwidth requirements, must evaluate whether ±50ppm is acceptable.

Q: Why does the substitute operate at fixed 3.3V instead of the original 1.7V ~ 3.6V range?

A: The ASCO-18.432MHZ-L-T3 is designed for standard 3.3V logic systems. Applications requiring operation at lower voltages (1.7V ~ 3.0V) or higher voltages (3.4V ~ 3.6V) cannot use this substitute. Verify your system's supply voltage specification before selection.

Q: Are there differences in long-term reliability between MEMS and crystal-based oscillators?

A: MEMS and crystal resonators exhibit different aging characteristics. Crystal oscillators typically show predictable frequency aging over time, while MEMS oscillators have different environmental sensitivity profiles. For applications requiring long-term frequency stability predictions, consult the manufacturer's detailed reliability data.

Q: Is the package size difference significant?

A: The substitute package is slightly smaller (1.60mm × 1.20mm versus 1.79mm × 1.25mm) with comparable height (0.70mm versus 0.69mm). For space-constrained applications, the smaller footprint may be beneficial. However, the different package technology (SMD No Lead versus UFBGA/CSPBGA) requires PCB design and assembly process validation.