scope:

This specification covers the general requirements for general purpose (BQ, BR, and BX characteristics) and temperature stable (BP characteristic) ceramic capacitors for use in switch mode power supplies. An acceleration factor of 8:1 has been used to relate life test data obtained at 200 percent of rated voltage at maximum rated temperature to rated voltage at rated temperature.

Capacitors covered by this specification should be classified by the style, as specified (see 3.1).

Capacitors specified herein (see 3.1) should be identified by a PIN which should consist of the basic number of the performance specification and a coded number. The coded number should provide information concerning the characteristic, specification sheet number, capacitance, capacitance tolerance, voltage, and, where applicable, lead configuration. The PIN should be in the following form with the coded number derived as indicated.

M49470 R 01 474 K C N * * * * * * * Performance Characteristic Performance Capacitance Capacitance Rated Lead specification (1.2.1.1) specification (1.2.1.2) tolerance voltage configuration indicating sheet number (1.2.1.3) (1.2.1.4) (see 1.2.1.5) MIL-PRF-49470 (indicating MIL-PRF-49470/1)

The characteristic refers to the voltage-temperature limits of the capacitor. The first letter (B) (not shown) identifies the rated temperature range of −55°C to +125°C. The second letter indicates the voltage-temperature limits as shown in table I. Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use in improving this document should be addressed to: US Army Communications-Electronics Command, ATTN: AMSEL-LC-LEO-E-EP, Fort Monmouth, NJ 07703-5023, by using the Standardization Document Improvement Proposal (DD Form 1426) appearing at the end of the document, or by letter. TABLE I. Characteristic.

Capacitance change with reference to +25°C Symbol Step A through step D of table VIII Step E through step G of table VIII -------------------------------------------------------------------------------------------- P 0 ppm/°C ±30 ppm/°C 0 ppm/°C ±30 ppm/°C Q ±15 percent +15, −50 percent R ±15 percent +15, −40 percent X ±15 percent +15, −25 percent

The nominal capacitance value, expressed in picofarads (pF) is identified by a three digit number; the first two digits represent significant figures and the last digit specifies the number of zeros to follow.

The capacitance tolerance is identified by a single letter in accordance with table II. TABLE II. Capacitance tolerance.

Symbol Capacitance tolerance ---------------------------------- J ±5 percent K ±10 percent M ±20 percent

The rated voltage for continuous operation at +125°C is identified by a single letter as shown in table III. TABLE III. Rated voltage.

Symbol Rated voltage A 50 B 100 C 200 E 500

The lead configuration is identified by single letter N, L, or J (see 3.1).

intended Use: