Surface mounted piezoelectric devices for frequency control and selection - Standard outlines and terminal lead connections - Part 3: Metal enclosures (IEC 61837-3:2015); German version EN 61837-3:2015
1Key Takeaways
This part of IEC 61837 deals with standard package dimensions and terminals for surface-mount devices (SMDs) used for frequency stabilization and selection in metal packages. It is based on IEC 61240, which standardizes design rules for package drawings of surface-mount devices.
2Expert Interpretation
An in-depth look at the DIN EN 61837-3:2016-04 standard, covering key technical requirements for surface mounting of metal-encased piezoelectric devices, including specifications, dimensional requirements, and terminal connections. This standard applies to surface-mount devices for frequency control and selection, providing detailed guidance on dimensional tolerances and structural configurations.
Standard Overview and Technical Background
DIN EN 61837-3:2016-04 is an international standard adopted by the European Committee for Electrotechnical Standardization (CENELEC) on May 20, 2015, and officially implemented on April 1, 2016. This standard replaces the 2001 version and provides standardized dimensions and terminal connection specifications for metal housings of surface-mounted piezoelectric devices.
Main technical changes and evolutions
Compared with DIN EN 61837-3:2001-09 version, the new version of the standard has made a number of important technical revisions:
| Changed items | Requirements of the 2001 version | Requirements of the 2016 version | Technical significance |
|---|---|---|---|
| Shell drawing perspective | Right view optional | Must include four views: top view, front view, right view, bottom view | Improve drawing completeness and manufacturing accuracy |
| Height marking | Use shell height | Use the total height symbol G or G with subscript number | Unified dimensioning system |
| Terminal spacing | No clear regulations | Must be marked center to center, with a reference dimension of 2.54n mm or 1.27n mm | Improve installation compatibility |
| Connection surface size | Mark minimum value | Mark maximum value | Simplify consumer use |
Metal shell configuration and classification
The standard defines a special surface mounting structure configuration, using SMS (Surface-Mounted, Special) as the identifier. The shell structure is divided into the following types according to the terminal type:
- L-type structure: Structure with bent terminals
- J-type structure: Structure with bent terminals (no identification for leadless versions)
The model name adopts a four-part structure: configuration symbol (SMS), lead structure (L/J), number of terminals, and two-digit serial number.
Dimension specifications and tolerance requirements
The standard specifies the key dimensional parameters of metal housings in detail:
| Parameter symbol | Description | Benchmark requirements | Applicable conditions |
|---|---|---|---|
| G | Total height | Indication with subscript numbers | Different height versions |
| e | Terminal spacing | 2.54n mm or 1.27n mm | Use 1.27n when shell size is <6mm |
| F | Length dimension | Numbers with Subscripts | Various Length Versions |
Terminal Connection and Wiring Specifications
Due to the unique SMD design of the SMS housing, the standard does not prescribe a uniform terminal assignment. The specific terminal configuration must be clearly stated in the product specification according to customer requirements. This flexibility allows manufacturers to optimize the configuration based on the specific characteristics of the piezoelectric device.
Recommendations for the implementation of the standard
Precautions in the design phase
During the product design phase, engineers should pay special attention to the following:
- Prepare housing drawings in strict accordance with the four views specified in the standard
- Terminal spacing must be marked center-to-center
- For housings with multiple heights, use subscripts such as G1 and G2
- Use maximum values instead of minimum values for connection surface dimensions
Manufacturing and quality control
Key points for quality control in the production process:
- Ensure that the resistance welding process meets the standard requirements
- The dimensional tolerance of the metal housing must be strictly controlled within the specified range
- The terminal bending molding process needs to ensure consistency and reliability
- For the J-type structure of the plastic carrier, pay attention to the matching of the thermal expansion coefficient of the materials
Transition period management
The standard sets a transition period until May 20, 2018. Enterprises should:
- Complete the technical conversion from the 2001 version to the 2016 version as soon as possible
- Update relevant design specifications and inspection standards
- Conduct compliance assessments for existing products
- Train technical personnel to master the requirements of the new standard
Application Areas and Market Impact
This standard applies to a variety of electronic equipment that requires frequency stability and selection, including:
- Frequency control modules for communication equipment
- Timing and synchronization systems in automotive electronics
- Precise clock sources for industrial control equipment
- High-stability oscillators for medical electronic equipment
The unified implementation of the standard will promote the interchangeability and reliability of surface mount piezoelectric devices, reduce manufacturing costs, and improve product quality consistency.
Technology Development Trends
As electronic devices develop towards miniaturization and high frequency, the technical requirements for surface-mounted piezoelectric devices continue to increase:
- The housing size is further reduced, requiring higher manufacturing precision
- High-frequency applications pose new challenges to terminal connection reliability
- Multi-chip packaging technology requires more flexible housing design
- Thermal management requirements promote the application of new materials and new structures
DIN EN 61837-3:2016-04 provides a standardized basis for these technological developments, ensuring compatibility and reliability between products from different manufacturers.