Overview
IEC 61837-2:2018 - Surface mounted piezoelectric devices for frequency control and selection - Standard outlines and terminal lead connections - Part 2: Ceramic enclosures (Edition 3.0, 2018) defines standard outlines and terminal lead connection recommendations for surface-mounted piezoelectric frequency-control devices housed in ceramic enclosures. This part is based on IEC 61240:2016 and updates the previous edition by revising figure notation and adding seven enclosure types, bringing the total to 45 enclosure types (listed in Table 1).
Key topics and requirements
- Scope: Applies to completed SMD devices for frequency control and selection in ceramic packages; specifies outline shapes, terminal lead structures and recommended land/terminal arrangements.
- Enclosure configurations: Uses descriptive configuration symbols:
- DCC (dual chip carrier)
- QCC (quad chip carrier)
- Designation system: A structured code (A B C D D’ E) is used to identify:
- configuration symbol (DCC/QCC)
- terminal lead structure (leadless default)
- number of terminal leads
- serial figure number
- terminal land arrangement (A/B/C variations for DCC, A/B for QCC)
- Ceramic enclosure dimensions: Provides standardized dimensions that apply only where they meet IEC 61240 requirements; intended to ensure consistent mechanical outlines and PCB footprint compatibility.
- Lead connections: Recommends terminal lead connection patterns and land arrangements for reliable soldering and mechanical mounting (leadless metal film terminals).
- Edition changes: Figures revised to align with IEC 61240:2016 notation; seven new enclosures added - DCC-6/5032A, DCC-6/3225A, DCC-4/3215C, DCC-6/2016A, DCC-2/2012C, DCC-2/1610C, DCC-4/1210C.
Applications and who uses it
- Component manufacturers - define package outlines, terminal metallurgy and produce compliant ceramic SMD resonators/crystals.
- PCB designers and layout engineers - use standardized land patterns and enclosure outlines to ensure correct footprints and soldering reliability.
- Product integrators and OEMs - select compatible SMD frequency-control parts and ensure interchangeability across suppliers.
- Procurement and quality assurance - verify supplier parts conform to internationally recognized outlines and connection recommendations.
- Test and reliability engineers - assess mechanical and solder joint robustness based on standard terminal arrangements.
Related standards
- IEC 61240:2016 - Piezoelectric devices - Preparation of outline drawings of SMD devices for frequency control and selection - General rules (normative reference for IEC 61837-2).
- Other parts of the IEC 61837 series cover non-ceramic enclosures and additional terminal/outline conventions.
Keywords: IEC 61837-2, surface mounted piezoelectric devices, SMD, ceramic enclosures, frequency control, terminal lead connections, DCC, QCC, IEC 61240, enclosure types, PCB footprint.