The MK3727H is a low drive, low cost, single output 3.3 Volt VCXO and PLL clock synthesizers designed to replace expensive VCXOs and crystals. The patented on-chip Voltage Controlled Crystal Oscillator accepts a 0 to 3.3 V input voltage to cause the output clocks to vary by ±115 ppm minimum. Using our analog Phase Locked Loop (PLL) techniques, the devices uses an external, fundamental mode 13.5 MHz pullable crystal input to produce output clocks of 27 MHz. The drive parameters are optimized for low EMI. The frequency of the on-chip VCXO is adjusted by an external control voltage input into pin VIN. Because VIN is high-impedance input, it can be driven directly from an PWM RC integrator circuit.


  • Packaged in 8-pin SOIC
  • Operating voltage of 3.3 V (±5%)
  • Single pullable output clock of 24 to 36 MHz
  • Uses a fundamental mode 12 to 18 MHz pullable crystal
  • On-chip patented VCXO with pull range of 230 ppm (minimum)
  • VCXO tuning voltage of 0 to 3.3 V
  • Low-drive output stage to reduce EMI
  • Advanced, low-power, sub-micron CMOS process
  • RoHS 5 (green) or RoHS 6 (green and lead free) compliant package

Product Options

Orderable Part ID Part Status Type Lead Count (#) Temp. Grade Pb (Lead) Free Carrier Type Buy Sample
Obsolete 8 C Yes Tube
Obsolete 8 C Yes Reel

Documentation & Downloads

Title Other Languages Type Format File Size Date
Datasheets & Errata
MK3727H Datasheet Datasheet PDF 233 KB
Application Notes & White Papers
AN-841 Pullable Crystal Selection and VCXO Tuning Application Note PDF 334 KB
AN-848 VCXO - Crystal Selection Application Note PDF 222 KB
AN-849 Loop Filter Component Selection for VCXO Based PLLs Application Note PDF 218 KB
AN-847 VCXO - Absolute Pull Range Application Note PDF 155 KB