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MK3727H - Block Diagram
MK3727H - Pinout


Low Drive 3.3V VCXO

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 Specification

Outputs (#)Output TypeOutput Freq Range (MHz)Input Freq (MHz)Inputs (#)Input TypeOutput Banks (#)Core Voltage (V)Output Voltage (V)
1LVCMOS24.000000 - 36.00000012.000000 - 18.0000001Crystal13.33.3

Product Options

Orderable Part IDPart StatusPkg. CodePkg. TypeLead Count (#)Temp. GradePb (Lead) FreeCarrier TypeSample & Buy
MK3727HLFObsoleteDCG8SOIC8CYesTubeCheck Availability
MK3727HLFTRObsoleteDCG8SOIC8CYesReelCheck Availability


Technical Documentation

Title Type Format File Size Datesort icon
Datasheets & Errata
MK3727H Datasheet Datasheet PDF 176 KB May 17, 2010
Apps Notes & White Papers
AN-841 Pullable Crystal Selection and VCXO Tuning Application Note PDF 248 KB Sep 23, 2014
AN-849 Loop Filter Component Selection for VCXO Based PLLs Application Note PDF 132 KB May 14, 2014
AN-848 VCXO - Crystal Selection Application Note PDF 138 KB May 14, 2014
show all (4)
AN-847 VCXO - Absolute Pull Range Application Note PDF 70 KB May 13, 2014