VMK3 and VMK4 32.768 kHz Tuning Fork Data Sheet VMK3 / VMK4 Description Vectrons VMK series 32.768 kHz tuning fork is used as a building block for 32.768 kHz oscillator clocks, and associatted divide-by to generate a 1 Hz / 1 second clock signal. The VMK3 is a 3.2x1.5 ceramic hermetically sealed package and VMK4 is 2.0x1.2. Applications Features 20 ppm Initial Accuracy Real Time CLocks -20/70C or -40/85C operating temperature Microprocessors Small Industry Standard Packages Wearables IoT Product is compliant to RoHS directive Bluetooth Low Energy and fully compatible with lead free assembly Medical, Hearing Aids, Meters and Monitors Security Block Diagram Crystal Page1Table 1. VMK3 Electrical Performance Parameter Symbol Min. Typ Max Units Nominal Frequency F 32.768 kHz NOM Crystal Mode Tuning Fork Operating Temperature Range, ordering option T -20 to 70, -40 to 85 C OP Frequency Stability 2 Stability Over T F -0.040 ppm/ C OP STAB Turnover Temperature 20 25 30 C Frequency Tolerance, referenced to 25 C F 20 ppm TOL Load Capacitance, ordering option C 6, 7, 9 or 12.5 pF L Equivalent Series Resistance ESR 70 KOhms Shunt Capacitance C 1.2 3.0 pF o VT-804 Motional Capacitance C 3.5 fF 1 Drive Level 1.0 uW Aging / 1st year F 3 ppm AGE Description Storage Temperature T -55 125 C STO Package 3.2 x 1.5 mm Weight 13 mg Product is compliant to RoHS directive and fully compatible with lead free assembly. Features VMK3 Package Drawing and Pad Layout 3.20.15 Top View Marking IMarknfing Iormanfortion mation MARKING 327YW3276YW WW wher where e 327 = 32.768 kH 3276 = 32.768 kHz z Y= Y ear of MY= Year of Manufacanufacturing turing 0.9 max WW = WWW = eek of MWeek of Manufacanufacturing turing Recommended Pad Layout 1.0 1.55 1.0 0.75 C0.25 0.1 1.8 All Dimensions in mm Page2 1.50.15