The LMK61A2-644M53SIAR: At this frequency it sits in the upper band of what a standard oscillator module can source directly — above the range of most crystal-based XOs — making it a fit for high-speed serial links, FPGA reference clocks, and networking PHY timing where the system needs a clean, single-frequency source without an external PLL. The 152 mA supply current at 3.3 V is the total power draw of the oscillator module itself — budget this into the 3.3 V clock rail alongside any fan-out buffers or clock dividers downstream. At 644.53 MHz, the output edge rate is fast enough that PCB trace impedance and termination matter; the oscillator expects a controlled 50 Ω environment on the output path.
It does not carry an automotive-grade qualification (AEC-Q100 is not listed), so it is not specified for under-hood or engine-bay deployment. The 6-QFM package (7 mm × 5 mm) is a compact, surface-mount module with a 6-pin footprint. The supplier device package designation 6-QFM (7x5) matches the 6-SMD Module case code — the same land pattern serves both designators. The module's internal construction integrates the resonator and oscillator circuitry in a single sealed package, eliminating the need for external load capacitors or feedback resistors that a discrete crystal oscillator would require.
Active lifecycle — current production status
The base product number is LMK61A2, which covers the fixed-frequency oscillator family. The suffix 644M53SIAR encodes the frequency (644.53 MHz), the supply voltage option, and the tape-and-reel packaging. If the design requires a different frequency within the LMK61A2 family, the same footprint and supply voltage apply — only the frequency code changes.