The Q33310FD00003 SG-310SDF 25 MHZ B is a 3.2 x 2.5 x 1.05mm 3.3V Crystal Oscillator with standby (ST) function. The SPXO standard SG-310SDF series oscillator with no load condition and to maintain stable operation, provide a by-pass capacitor at a location as near as possible to the power source terminal of the crystal product.