ECS-35-S-4 Crystal Equivalent & Substitute Parts

Part Overview

The ECS-35-S-4 is a 4.679545 MHz through-hole crystal oscillator in HC-49/US package configuration, designed for fundamental mode operation with 200 Ohms equivalent series resistance. This component is classified as "Not For New Designs," indicating it has been superseded in the manufacturer's product roadmap. Finding equivalent substitute parts is necessary for legacy system maintenance, repair operations, and applications where this specific frequency and package format remain in use.

Substiute Parts

ECS-35-S-4

ECS Inc.In Stock: 1159ECS-35-S-4 Datasheet

Current PartRFQ

ECS-35-S-4X

ECS Inc.In Stock: 1910ECS-35-S-4X Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the ECS-35-S-4 is determined by strict equivalence across the following critical parameters:

• Frequency: 4.679545 MHz (exact match required)
• Frequency Tolerance: ±30ppm (exact match required)
• ESR: 200 Ohms (exact match required)
• Package / Case: HC-49/US (exact match required)
• Mounting Type: Through Hole (exact match required)
• Operating Temperature Range: -10°C to 70°C (exact match required)
• Operating Mode: Fundamental (exact match required)

The ECS-35-S-4X meets all substitution criteria as a parametric equivalent. Both parts share identical electrical specifications, physical dimensions, and functional characteristics. The primary distinction lies in product status and compliance certifications.

Parameter Comparison

Engineering Selection Recommendations

The ECS-35-S-4X is the direct parametric equivalent for the ECS-35-S-4. Both components are electrically and mechanically identical across all specified parameters. Selection between these parts should be based on the following factors:

For legacy system repairs and maintenance where the original ECS-35-S-4 is no longer available, the ECS-35-S-4X provides full functional compatibility with identical electrical performance and physical form factor.

The ECS-35-S-4X carries Active product status, indicating ongoing manufacturer support and availability. The ECS-35-S-4 is designated "Not For New Designs," reflecting its superseded status in the product line.

Compliance considerations: The ECS-35-S-4X is ROHS3 compliant, whereas the ECS-35-S-4 is RoHS non-compliant. Both parts are REACH Unaffected and classified under ECCN EAR99. For applications subject to RoHS compliance requirements, the ECS-35-S-4X is the appropriate selection.

Frequently Asked Questions (FAQ)

Q: Can the ECS-35-S-4X be used as a direct replacement for the ECS-35-S-4?

A: Yes. The ECS-35-S-4X is a parametric equivalent with identical frequency, tolerance, ESR, package, and operating specifications. No circuit modifications are required for substitution.

Q: What is the difference between the ECS-35-S-4 and ECS-35-S-4X?

A: The parts are electrically and mechanically identical. The primary differences are product status (Active vs. Not For New Designs) and RoHS compliance (ROHS3 Compliant vs. non-compliant). The ECS-35-S-4X represents the current production equivalent.

Q: Are the physical dimensions identical between both parts?

A: Yes. Both the ECS-35-S-4 and ECS-35-S-4X share identical dimensions of 0.447" L x 0.183" W (11.35mm x 4.65mm) with a maximum seated height of 0.138" (4.60mm). They are mechanically interchangeable in HC-49/US through-hole applications.

Q: Does the RoHS compliance difference affect electrical performance?

A: No. RoHS compliance relates to material composition and environmental standards, not electrical characteristics. Both parts deliver identical frequency, tolerance, and ESR specifications.

Q: What is the frequency tolerance specification, and why is it important?

A: The frequency tolerance is ±30ppm, meaning the actual frequency will not deviate more than 30 parts per million from the nominal 4.679545 MHz specification. This tolerance is critical for applications requiring precise timing or frequency-dependent circuit operation.

Q: Can these crystals be used in surface-mount applications?

A: No. Both the ECS-35-S-4 and ECS-35-S-4X are through-hole mounted components in HC-49/US package format. They are designed for insertion into PCB holes and are not suitable for surface-mount assembly.