SLIM-MO-64 rev B
Master Oscillator
Updated 4-30-08.  Update for Rev A, which is a component change, only.
Updated 6-13-08.  Update for Rev B, which is a component change, only.
SLIM-MO-64,  Master Oscillator, size-A
Use your mouse's "right click" and "Save Link" to download:
a.   SKSLIM-MO-64 rev B, Schematic, in ExpressPCB software.
b.   LAYSLIM-MO-64 rev A, Layout, in ExpressPCB software. Use this drawing to locate parts on the Board
c.   PLSLIM-MO-64 rev B, Parts List for SLIM Board, in .txt format.  Open with Exel or Lotus, etc.
d.   PWB-MOB, Base artwork for PWB, in ExpressPCB software.  Use this drawing to order the pwb from Express.
This SLIM is constructed on a common printed wiring board, the PWB-MOB.  Click to go to the page describing the Master Osc or Buffer.

    The SLIM-MO-64, Master Oscillator, contains a 64 MHz oscillator and 3 buffered line drivers.  Each output is 5 volt CMOS that can drive a 50 ohm line that is terminated with either, a high impedance load, or 50 ohms.  A 33 ohm resistor is shown as a series element in each output.

Revision A:
    The only change from the original design is: delete the input ferite bead, FB1, and replace it with a 10 ohm resistor, R12.  This decreases the +10 volt, supply line noise.
 Revision B:
    The only change from the previous revision is: Change R1, R2, and R3 from 49.9 ohms to 33 ohms for a better driving source impedance.

SKSLIM-MO-64, Schematic of Master Oscillator, SLIM-MO-64
slim/skslim_mo_64.gif
       A 33 ohm resistor is shown as a series element in each output.  For a 50 ohm line, with a high impedance load at the end of that line, the mismatched load will create a reflection.  The reflected signal will be dissipated in the series 33 ohm resistor plus the internal resistance of the driver (17 ohms).  For a 50 ohm line, with a 50 ohm load at the end of that line, the 50 ohm load will receive a 2.5 volt peak to peak square wave.  If this is not sufficient, the 33 ohm series resistor can be replaced with a low impedance coupling capacitor (.01 uf for 64 MHz).
  The 64 MHz oscillator can be replaced with any oscillator in the CTS series of CB3 oscillators.  There are other crystal oscillators with this footprint, but I have not researched them.  Once temperature equalibrium has been reached, this oscillator is extremely stable.
    If this module is used in a system where fewer outputs are required, omit the drivers that are not needed.  This reduces power consumption.

LAYSLIM-MO-64, Layout of Master Oscillator, SLIM-MO-64
slim/layslim_mo_64.gif  slim/mastosc.JPG
    Notice, in the layout and the photo, that there are several pads with no components.  This is because the pwb (PWB-MOB) can be used for other functions, such as a sine to square converter.