1 to 60 MHz, Stratum 3E DCOCXO

The SiT5721 is the industry’s smallest Stratum 3E digitally controlled OCXO with ±5 ppb frequency stability and ±40 ppt/°C frequency slope (ΔF/ΔT). This device is engineered to provide the best dynamic performance. Leveraging SiTime’s unique DualMEMS™ and TurboCompensation™ temperature sensing technology, this DCOCXO delivers the most stable timing in the presence of environmental stressors such as airflow, temperature perturbation, vibration, shock, and electromagnetic interference (EMI).

The environmental robustness of SiT5721 enables unmatched ease-of-use and simplifies system design:

  • Can be placed anywhere on the PCB
  • No mechanical cover or shielding needed for thermal isolation
  • No external regulators required
  • No additional sealing needed for high humidity environments

The SiT5721 can be factory-programmed to any frequency between 1 and 60 MHz. In addition to industry leading performance, the DCOCXO is offered in a 9 x 7 mm package, the smallest Stratum 3E OCXO available.  

World's smallest DCOCXO, 75% smaller footprint and 40% thinner
Oscillator Type DCOCXO
Frequency 1 to 60 MHz
Frequency Stability (ppm) ±0.005 (±5 ppb), ±0.008 (±8 ppb)
Output Type LVCMOS, Clipped sinewave
Operating Temperature Range (°C) -20 to 70, -40 to +80
Pull Range (ppm) ±6.25
Voltage Supply (V) 3.3
Package Type (mm²) 9.0 x 7.0
Features Frequency Slope: ±40 ppt/°C; Contact SiTime for ±3 ppb stability; Contact SiTime for -40° to 105°C;
Availability Sampling

10 times better dynamic stability under airflow and fast temp. ramp, ensures best system performance in harsh environments

  • ±5 or ±8 ppb over-temp. stability
  • 2e-11 ADEV at 10 sec under airflow
  • ±40 ppt/°C frequency slope (ΔF/ΔT)

Unmatched ease-of-use, simplifying system design

  • No restrictions on PCB placement
  • No mechanical shielding needed for thermal isolation
  • Resistant to humidity
  • On-chip regulators, no need for external LDOs or ferrite beads

Smallest size, ideal for high density and small form factor systems

  • 9 x 7 mm footprint, 75% smaller
  • 6.5 mm height, 40% thinner

Higher reliability and robustness

  • 20 times better vibration resistance, ideal for outdoor pole mounted equipment
  • Resistant to microphonic and/or board bending effects, ideal for large telecom PCBs
  • Semiconductor-level quality and reliability, batch to batch consistency
  • No activity dips or micro jumps

Programmable platform eliminates long lead times and customization cost associated with legacy quartz OCXO

  • Any frequency from 1 to 60 MHz
  • LVCMOS or clipped sine-wave outputs 
  • SONET/SDH Stratum 3E
  • 4G/5G RRH, DU
  • Base Stations
  • Core and edge routers
  • Carrier class switches
  • IEEE 1588 boundary clocks
  • IEEE 1588 grandmasters
  • GNSS disciplined timing modules
  • Instrumentation
  • Power & energy
  • Defense & aerospace
  • Long-range communications

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SiT6731 Eval Board User Manual – Evaluate oscillator performance

Frequency Slope (dF/dT) Calculator – Calculate frequency slope over temperature

Time Error Simulation Software – Simulate and analyze the impact of the local oscillator

Reliability Calculator – Get FIT/MTBF data for various operating conditions

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