scope:

This specification covers the general requirements for insulated, film, fixed resistors of 1, 2, 5, and 10 percent resistance tolerance. These resistors are capable of full-load operation at an ambient temperature of 70°C and have a resistance-temperature characteristic of 100 and 350 parts per million per degree Celsius (PPM/°C). The resistors will have life failure rate levels ranging from 1.0 to 0.001 percent per 1,000 hours (see 1.2.1.4). These failure rate levels are established at a 60-percent confidence level on the basis of life tests. The failure rate level, identified by the appropriate symbol, is referred to operation at full rated wattage at 70°C, with a permissible change in resistance of 4 percent in 10,000 hours as the criteria for failure. Supplement 1 provides a summary of performance characteristics for these resistors. The term Part or Identifying Number (PIN) is equivalent to the term (part number, identification number, type designator, etc.) which was previously used in this specification. A part per million (PPM) quality system is used for documenting and reporting the average outgoing quality of resistors supplied to this specification. Statistical process control (SPC) techniques are required in the manufacturing process to minimize variation in production of resistors supplied to the requirements of this specification.

The PIN shall be in the following form, and as specified (see 3.1).

The style is identified by the three-letter symbol RLR followed by a two-digit number; the letters identify established reliability, insulated, film, fixed resistors, and the number identifies the size and power rating of the resistors. Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use in improving this document should be addressed to U.S. Army Laboratory Command, ATTN: SLCET-R-S, Fort Monmouth, NJ 07703-5000 by using the self-addressed Standardization Document Improvement Proposal (DD Form 1426) appearing at the end of this document or by letter.

The terminals are identified by a single letter in accordance with table I. TABLE I. Terminal.

Symbol Terminal ---------------------------------------------------------------- C 1/ Solderable/weldable (type C31, C32, or C52 of MIL-STD-1276) 1/ The maximum thickness of 200 microinches is not applicable.

The resistance tolerance is identified by a single letter in accordance with table II. TABLE II. Resistance tolerance.

Symbol Resistance tolerance --------------------------------------------------------- Percent (±) F - - - - - - - - - - 1 G - - - - - - - - - - 2 J - - - - - - - - - - 5 K - - - - - - - - - - 10

The life failure rate level designation as shown in table III is signified by a single letter (M, P, R, or S), which identifies the life failure rate level for which the resistor is qualified (see 4.4). TABLE III. Life failure rate level (established at 60-percent confidence).

Failure rate level Failure rate level designation (%/1,000 hr) --------------------------------------------------------- M - - - - - - - - - - 1.0 P - - - - - - - - - - 0.1 R - - - - - - - - - - 0.01 S - - - - - - - - - - 0.001

The nominal resistance expressed in ohms is identified by a resistance designation utilizing four digits. Minimum and maximum resistance values shall be as specified (see 3.1).

The four digit resistance designation is applicable to resistance tolerances "F" (1.0 percent), "G" (2.0 percent), "J" (5.0 percent), and "K" (10.0 percent). The nominal resistance identified by four digits; the first three digits represent significant figures and the last digit specifies the number of zeros to follow. When the value of resistance is less than 100 ohms, or when fractional values of an ohm are required, the letter "R" shall be substituted for one of the significant digits to represent the decimal point. When the letter "R" is used, succeeding digits of the group represent significant figures. The resistance value designations are shown in table IV. Standard values for every decade shall follow the sequence demonstrated for 10 to 100 decade in table V. Resistance values not listed in table V for the appropriate resistance tolerance shall be considered as not conforming to the specification. Although resistance tolerances "G", "J", and "K" normally requires less than three significant figures to adequately describe the true resistance value, for the purpose of this specification, the nominal value shall be three significant figures followed by the fourth digit to signify the number of zeros to follow. TABLE IV. Designation of resistance values for resistance-tolerances of 1.0, 2.0, 5.0, and 10.0 percent.

Designation Resistance ohms --------------------------------------------------------------------------------- 1R00 to 9R76 incl. - - - - - - - - 1.00 to 9.76 incl. 10R0 to 97R6 incl. - - - - - - - - 10.0 to 97.6 incl. 1000 to 9760 incl. - - - - - - - - 100 to 976 incl. 1001 to 9761 incl. - - - - - - - - 1,000 to 9,760 incl. 1002 to 9762 incl. - - - - - - - - 10,000 to 97,600 incl. 1003 to 9763 incl. - - - - - - - - 100,000 to 976,000 incl. 1004 to 9764 incl. - - - - - - - - 1,000,000 to 9,760,000 incl. 1005 to 9765 incl. - - - - - - - - 10,000,000 to 97,600,000 incl.

intended Use:

These film resistors described herein are intended to be used in electronic circuits where semiprecision characteristics and small sizes are required.