CRYSTAL UNITS For Microprocessor CRYSTAL UNITS / AT-51SERIES These crystal units are intended for use as reference clocks in microprocessors or the like. ■ Features 8 Meets the requirements for various applications with the availability of abundant standard frequencies. 8 Surface mount type. 8 Taping type and gull-wing type are available for automatic mounting. AT-51 AT-51CD2 ■ Specification Type Item Frequency Range Overtone AT-51, AT-51CD2 3.1875 ~ 28.63636 MHz Fundamental 26 ~ 75 MHz 3rd overtone Frequency Tolerance (25±3˚C) ± 50 × 10-6 Temperature Characteristics (in reference to +25˚C) ± 50 × 10-6 Operating Temperature Range –10 ~ +60˚C 4 See Table Equivalent Series Resistance 500 µW (3.541MHz max) 50 µW (3.541 ~ 28.63636MHz) Drive Level 500 µW(1000 µW max) (1000 µW max) 16pF Standard Load Capacitance Series –40 ~ +85˚C Operable Temperature Range Typical Frequency (MHz) 3.579545 3.6864 4.0 4.194304 4.332 4.433619 4.5 4.9152 6.0 7.2 7.3728 7.68 8.0 9.8304 10.0 10.25 11.0592 12.0 13.824 14.31818 16.0 16.9344 17.734475 18.432 20.0 24.576 25.0 27.0 28.63636 33.8688 36.864 61.5 Fundamental ■ Dimensions 4 Table Equivalent Series Resistance (Ω) (mm) 0.2 max 5.5±0.3 5.08 max 4.65 max AT-51 Fundamental Reference footprint 6.0 0.8±0.15 4.7±0.1 4.88±0.20 12.4±0.3 11.4±0.2 2.0 3.5 ~ 20±1 +0.05 ø 0.43 –0.03 11.05 max Overtone 3.7 max 3.70 max 10.10 max (mm) 10.1 max 9.0 4.88±0.2 AT-51CD2 58 Frequency Range (MHz) Equivalent Series Resistance (Ω) 3.1875 ~ 3.2 400 max 3.2 ~ 3.5 250 max 3.5 ~ 4.0 150 max 4.0 ~ 4.5 120 max 4.5 ~ 5.0 100 max 5.0 ~ 6.0 80 max 6.0 ~ 8.0 75 max 8.0 ~ 10.0 60 max 10.0 ~ 12.0 50 max 12.0 ~ 28.63636 40 max 26.0 ~ 35.0 140 max 3rd overtone 35.0 ~ 48.0 100 max 48.0 ~ 75.0 80 max