ECS-3X8 32.768 kHz Crystal Equivalent & Substitute Parts

Part Overview

The ECS-3X8 is a 32.768 kHz tuning fork crystal designed for through-hole mounting in cylindrical can packages. This component operates at fundamental mode with 12.5pF load capacitance and 35 kOhms equivalent series resistance, suitable for real-time clock and timing applications. The part is classified as "Not For New Designs," making identification of active equivalent alternatives essential for ongoing production and new project implementations.

Key Parameters

Parameter	Value
Frequency	32.768 kHz
Frequency Tolerance	±20ppm
Load Capacitance	12.5pF
ESR (Equivalent Series Resistance)	35 kOhms
Operating Mode	Fundamental
Operating Temperature Range	-10°C ~ 60°C
Mounting Type	Through Hole
Package Type	Cylindrical Can, Radial
Moisture Sensitivity Level	1 (Unlimited)

Substitute Part Grouping Explanation

Substitution eligibility is determined by strict parameter matching across electrical and mechanical specifications. All substitute parts listed maintain identical frequency (32.768 kHz), frequency tolerance (±20ppm), load capacitance (12.5pF), operating mode (Fundamental), temperature range (-10°C ~ 60°C), mounting type (Through Hole), package type (Cylindrical Can, Radial), and moisture sensitivity level (MSL 1).

Substitute parts are grouped into two categories:

Direct Mechanical Equivalents: Parts with identical physical dimensions (0.122" Dia x 0.323" L / 3.10mm x 8.20mm) and ESR (35 kOhms). These provide pin-for-pin and footprint compatibility.

Parametric Equivalents with Dimensional Variation: Parts with matching electrical parameters but different physical dimensions (0.083" Dia x 0.244" L / 2.10mm x 6.20mm or smaller). These require PCB layout verification but maintain full electrical compatibility.

Near-Equivalent with ESR Variance: Parts matching all parameters except ESR (50 kOhms vs. 35 kOhms). These require circuit analysis to confirm acceptable performance.

Parameter Comparison

Part Number	Manufacturer	Frequency	Tolerance	Load Cap	ESR	Dimensions (mm)	Product Status	RoHS Status
ECS-3X8	ECS Inc.	32.768 kHz	±20ppm	12.5pF	35 kOhms	3.10 x 8.20	Not For New Designs	Non-compliant
ECS-.327-12.5-13	ECS Inc.	32.768 kHz	±20ppm	12.5pF	35 kOhms	2.10 x 6.20	Not For New Designs	Request verification
ECS-.327-12.5-13X	ECS Inc.	32.768 kHz	±20ppm	12.5pF	35 kOhms	2.10 x 6.20	Active	ROHS3 Compliant
ECS-.327-12.5-8X	ECS Inc.	32.768 kHz	±20ppm	12.5pF	35 kOhms	3.10 x 8.20	Active	ROHS3 Compliant
AB26T-32.768KHZ	Abracon LLC	32.768 kHz	±20ppm	12.5pF	35 kOhms	2.10 x 6.20	Active	ROHS3 Compliant
G23270023	Diodes Incorporated	32.768 kHz	±20ppm	12.5pF	35 kOhms	2.00 x 6.00	Active	ROHS3 Compliant
VT200F-12.5PF20PPM	Seiko Instruments	32.768 kHz	±20ppm	12.5pF	50 kOhms	1.88 x 6.00	Active	ROHS3 Compliant

Engineering Selection Recommendations

For Direct Replacement (Identical Footprint): ECS-.327-12.5-8X is the primary recommendation. It maintains the original 3.10mm x 8.20mm dimensions, 35 kOhms ESR, and all electrical parameters while offering Active product status and ROHS3 compliance. This part requires no PCB layout modification.

For New Designs with Layout Flexibility: ECS-.327-12.5-13X is recommended. It provides Active status, ROHS3 compliance, and full electrical equivalence with a smaller 2.10mm x 6.20mm footprint. PCB layout adjustment is required.

For Multi-Source Strategy: AB26T-32.768KHZ (Abracon LLC) and G23270023 (Diodes Incorporated) provide alternative manufacturer sources with Active status and ROHS3 compliance. Both maintain 35 kOhms ESR and full electrical compatibility, though with reduced physical dimensions requiring layout verification.

For ESR-Tolerant Applications: VT200F-12.5PF20PPM (Seiko Instruments) is acceptable only in circuits designed to tolerate 50 kOhms ESR. The 15 kOhms ESR increase may affect oscillation startup characteristics and frequency stability margins. Circuit simulation is required before implementation.

Compliance Consideration: All recommended active substitutes are ROHS3 compliant, addressing regulatory requirements for the obsolete ECS-3X8 (RoHS non-compliant).

Frequently Asked Questions (FAQ)

Q: Can ECS-.327-12.5-13X replace ECS-3X8 without PCB modification?

A: No. ECS-.327-12.5-13X has a smaller footprint (2.10mm x 6.20mm vs. 3.10mm x 8.20mm). PCB layout changes are required. For direct replacement without modification, use ECS-.327-12.5-8X.

Q: What is the impact of ESR difference between ECS-.327-12.5-8X (35 kOhms) and VT200F-12.5PF20PPM (50 kOhms)?

A: Higher ESR increases power consumption and may affect oscillation startup time and frequency stability margins. Use VT200F-12.5PF20PPM only if the circuit design accommodates 50 kOhms ESR. Consult oscillator circuit specifications.

Q: Are all substitute parts RoHS compliant?

A: All active substitute parts listed (ECS-.327-12.5-13X, ECS-.327-12.5-8X, AB26T-32.768KHZ, G23270023, VT200F-12.5PF20PPM) are ROHS3 compliant. ECS-.327-12.5-13 requires inventory verification for RoHS status.

Q: Which substitute offers the best availability?

A: ECS-.327-12.5-8X has the highest inventory (71,254 pcs). G23270023 (Diodes Incorporated) provides 5,354 pcs. Both are Active products with confirmed stock.

Q: Can I use different manufacturers interchangeably?

A: Yes, provided electrical parameters match. ECS Inc., Abracon LLC, Diodes Incorporated, and Seiko Instruments all provide 32.768 kHz ±20ppm crystals with 12.5pF load capacitance and 35 kOhms ESR (except Seiko at 50 kOhms). Verify physical dimensions against PCB layout requirements.

Q: What is the difference between ECS-.327-12.5-13 and ECS-.327-12.5-13X?

A: Both have identical electrical specifications and 2.10mm x 6.20mm dimensions. ECS-.327-12.5-13X is Active with ROHS3 compliance, while ECS-.327-12.5-13 is Not For New Designs with unverified RoHS status. Use ECS-.327-12.5-13X for new applications.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message