32.768 kHz — the RTC heartbeat
The ECS-.327-8-14X: 32.768 kHz is the universal RTC frequency, and this part runs in fundamental mode at that rate — meaning no sub-harmonic spurious responses that plague overtone crystals in timekeeping circuits. Frequency tolerance is ±20 ppm at 25 °C; the operating range of -10°C to 60°C will shift the pull range slightly, but for a standard calendar clock the ±20 ppm figure sets the timing budget — roughly ±1.7 seconds per day maximum deviation, well within typical RTC spec. Load capacitance is 8 pF — this is the value the driving MCU clock pin must present to the crystal terminals including trace and stray capacitance. Most RTC MCU families (DS1337, PCF8563, and similar) are designed around this 8 pF load; check the MCU oscillator section to confirm total capacitance on the clock pins sums to 8 pF.
ESR and physical form
Equivalent series resistance is 40 kΩ — acceptable for a tuning fork at 32.768 kHz and well within the drive capability of standard RTC oscillator circuits, so startup time is not a concern. The cylindrical can, radial package mounts through-hole on 1.50 mm diameter pads — a standard footprint for discrete RTC crystals on single-sided MCU boards, with the two wire leads bent to suit the pad pitch on the PCB.
Production status and sourcing
No official second-source cross-reference or successor order code appears in the ECS lifecycle record for this part — the series and package uniquely identify the ordering code, so confirm the full suffix before committing to a BOM position.