BS EN 62047-4-2010 pdf download.Semiconductor devices Micro-electromechanica devices Part 4 : Generic specification for MEMS.
These subgroups may not all be required. The required subgroups are specified in the relevant sectional or blank detail specification.
6.2.3.3 Inspection requirements
The statistical sampling procedures described in 6.2.4 shall be used.
6.2.3.3.1 Procedure in case of failure in periodic tests
When a group B failure occurs, the corresponding group C tests (see 6.2.3.3) are invalid. In the event of failing periodic inspection tests, see the rules of procedure given in 3.1.8 of IEC
QCOO1 002-3.
6.2.3.4 SwitchIng rules for reduced Inspection In Group C
The procedure is applicable to subgroups of Group C tests having a periodicity of 12 months or less when specifically permitted by the sectional specification. It shall not be applied to endurance tests unless otherwise prescribed in the relevant specification.
The relevant specification shall describe any limitations with respect to values, styles, etc., of a device in the use of this procedure.
See the switching rules of procedure given in 3.2.8 of IEC OC 00 1002-3.
6.2.3.5 Delivery of device subjected to destructive or non-destructive tests
Tests considered as destructive are marked (D) in the sectional or blank detail specification. Devices subjected to destructive tests shall not be included in the lot for delivery. Devices subjected to non-destructive environmental tests may be delivered provided they are re-tested according to Group A requirements and satisfy them.
6.2.3.6 Delayed deliveries
Before delivery of lots which have been stored longer than the storage time, and in conditions specified in the relevant sectional or blank detail specification, the lots or the quantities to be delivered shall undergo the specified Group A inspection and Group B interconnection ability tests.
6.2.4 StatIstical sampling procedures
6.2.4.1 General
For Group A, B and C inspections, either the AOL sampling procedure or the zero-defects sampling procedure shall be used. The detail specification shall specify which of the procedures is to be used.
6.2.4.2 AQL sampling plans
See ISO 2859-1 and Annex A. There are three types of sampling plans: single, double and multiple. When several types of plans are available for a given AOL and code letter, any one may be used.
6.2.4.3 Zero-defects sampling plans See IEC 61193-2 and Annex A.
6.2.5 Endurance tests
Endurance tests shall be specified in the detail specification.
6.2.6 Endurance tests where the failure rate is specified
6.2.6.1 General
Failure rate used in this standard is defined as a percentage per thousand hours. Endurance tests with the specified failure rate shall be specified in the detail specification. Endurance tests performed on devices at, or within, their maximum ratings shall be considered nondestructive.
6.2.6.2 Selection of samples
Samples for endurance tests shall be selected at random from the inspection lot (see Annex A). The sample size for a 1 000 h test shall be given in the detail specification (see 6.2.4).
The acceptance number shall be the one associated with the particular sample size chosen.
This option shall be used only once for each submission. When this option is chosen, a new total sample size (initial plus added) shall be chosen by the manufacturer. A quantity of additional devices sufficient to increase the sample to the newly chosen total sample size shall be selected from the lot. The new acceptance number shall be the one associated with new total sample size chosen. The added sample shall be subjected to the same endurance test conditions and time period as the initial sample. If the total observed number of detectives (initial plus added) does not exceed the acceptance number for the total sample, the lot shall be accepted: if the observed number of defectives exceeds the new acceptance number, the lot shall be rejected.
6.2.6.5.3 Extension of endurance test period
If an endurance test time periods less than 1 000 h is used and the number of failures observed in the initial sample exceeds the acceptance number, the manufacturer may. instead of adding additional samples, choose to extend the test time of the entire initial sample to 1 000 h and determine a new acceptance number. The new acceptance number shall be one associated with the largest sample size in the specified column which is less than, or equal to, the sample size being tested. A device which is a failure at the initial reading interval shall be considered as such at the 1 000 h reading interval. If the observed number of detectives exceeds this acceptance number, the lot shall not be accepted.
6.2.7 Accelerated test procedures
Accelerated test may be applied when the acceleration factor is defined in advance according
to the proper theoretical analysis or experimental data.
7 Test and measurement procedures
7.1 Standard conditions and general precautions
7.1.1 Standard conditions
Unless otherwise specified, all measurements are carried out under the following atmospheric conditions:
– ambient temperature 25 °C ± 3 °C;
– relative humidity between 25 % and 85 %:
— atmospheric pressure between 86 kPa and 106 kPa.
Measurements may be carried out at other temperatures, provided the National Supervising Inspectorate is satisfied that the device will conform to the detail specification when tested at an ambient temperature of 25 C ± 1 C and relative humidity between 48 % and 52 % when this is important.BS EN 62047-4-2010 pdf download.