STDCSF4-12M Equivalent & Substitute Parts

Part Overview

The STDCSF4-12M is a 12 MHz fundamental mode crystal oscillator manufactured by NDK America, Inc., designed for surface mount applications. This part operates at 12.0000 MHz with ±20 ppm frequency tolerance and 8 pF load capacitance. The STDCSF4-12M is classified as Not For New Designs, indicating it has been superseded in the manufacturer's product line. Finding equivalent substitute parts is necessary for applications requiring continued supply, design updates, or inventory optimization while maintaining electrical and mechanical compatibility.

Substiute Parts

STDCSF4-12M

NDK America, Inc.In Stock: 2270STDCSF4-12M Datasheet

Current PartRFQ

STDCSK4-12M

NDK America, Inc.In Stock: 12725STDCSK4-12M Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the STDCSF4-12M is determined by the following critical parameters:

• Frequency: Must be 12 MHz
• Frequency Tolerance: Must be ±20 ppm or tighter
• Load Capacitance: Must be 8 pF
• Operating Mode: Must be Fundamental
• Operating Temperature Range: Must cover -10°C to 70°C minimum
• Mounting Type: Must be Surface Mount
• Package / Case: Must be 2-SMD, No Lead
• RoHS Compliance: Must be RoHS Compliant
• Moisture Sensitivity Level: Must be MSL 1 or better

The STDCSK4-12M meets all substitution criteria. While the ESR differs (100 Ohms versus 80 Ohms), this parameter remains within acceptable tolerance for fundamental mode crystal operation at this frequency and load capacitance. The physical dimensions differ slightly, but both parts conform to the 2-SMD, No Lead package standard and are compatible with equivalent PCB footprints.

Parameter Comparison

Engineering Selection Recommendations

The STDCSK4-12M is a direct substitute for the STDCSF4-12M based on electrical parameter equivalence and compliance certifications. Both parts are RoHS Compliant with MSL 1 rating, ensuring equivalent environmental and regulatory compliance.

The STDCSK4-12M carries Active product status, whereas the STDCSF4-12M is Not For New Designs. This distinction makes the STDCSK4-12M the preferred choice for new designs and long-term supply continuity.

The primary design consideration is the ESR difference: the STDCSK4-12M operates at 100 Ohms compared to the STDCSF4-12M at 80 Ohms. This 20 Ohm increase remains within acceptable operating parameters for 12 MHz fundamental mode crystals with 8 pF load capacitance and does not introduce circuit compatibility issues in standard oscillator configurations.

The STDCSK4-12M features a smaller physical footprint (5.00mm x 3.20mm versus 8.00mm x 4.50mm) and lower profile (1.50mm versus 2.00mm), which may provide PCB layout advantages in space-constrained applications. Verify PCB footprint compatibility before implementation.

Frequently Asked Questions (FAQ)

Q: Can the STDCSK4-12M replace the STDCSF4-12M in existing designs?

A: Yes. Both parts share identical frequency (12 MHz), frequency tolerance (±20 ppm), load capacitance (8 pF), operating mode (Fundamental), temperature range (-10°C to 70°C), and package type (2-SMD, No Lead). The ESR difference (100 Ohms versus 80 Ohms) does not prevent substitution in standard oscillator circuits. Verify PCB footprint compatibility due to dimensional differences.

Q: What is the significance of the ESR difference between these parts?

A: ESR (Equivalent Series Resistance) affects crystal startup time and power consumption in oscillator circuits. The STDCSK4-12M's 100 Ohm ESR versus the STDCSF4-12M's 80 Ohm ESR represents a 20 Ohm increase. This difference remains within acceptable tolerance for 12 MHz fundamental mode operation and does not typically require circuit redesign.

Q: Why are the physical dimensions different if both are 2-SMD, No Lead packages?

A: The 2-SMD, No Lead package designation defines the electrical interface and lead configuration, not the overall case size. Manufacturers produce multiple case sizes within the same package family. The STDCSK4-12M uses a smaller case (NX5032GA series) compared to the STDCSF4-12M (NX8045GB series). Both conform to 2-SMD, No Lead standards but occupy different PCB footprints. Confirm footprint compatibility with your PCB design before substitution.

Q: Is the STDCSK4-12M suitable for new product designs?

A: Yes. The STDCSK4-12M carries Active product status, making it the appropriate choice for new designs. The STDCSF4-12M is classified as Not For New Designs and should not be selected for new applications.

Q: Are both parts RoHS Compliant?

A: Yes. Both the STDCSF4-12M and STDCSK4-12M are RoHS Compliant with MSL 1 (Unlimited) moisture sensitivity rating, ensuring equivalent environmental and regulatory compliance.