Difference between revisions of "DRIVE50"

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* 5x paralleled [http://cva.stanford.edu/classes/cs99s/datasheets/74AC14.pdf 74AC14] drivers
 
* 5x paralleled [http://cva.stanford.edu/classes/cs99s/datasheets/74AC14.pdf 74AC14] drivers
 
** 24mA per pin max current output
 
** 24mA per pin max current output
 +
*** Symmetric high-low drive levels
 
** Short-circuit proof
 
** Short-circuit proof
 
*** 5V, 250 Ohms to ground is 20 mA (pins are rated for 24 mA
 
*** 5V, 250 Ohms to ground is 20 mA (pins are rated for 24 mA

Revision as of 17:12, 6 July 2022

DRIVE50 FRONT 3D.png

50 Ohm Driver Card

  • "TTL" Level Line driver
  • 50 or 75 Ohm output impedance
  • BNC or SMA output connector
  • 10K pull-up on input
  • Card is non-inverting
  • 3V-5V power
  • 3-pin right angle 0.1" pitch input connector
  • (4) 4-40 mounting holes

Driver

  • 5x paralleled 74AC14 drivers
    • 24mA per pin max current output
      • Symmetric high-low drive levels
    • Short-circuit proof
      • 5V, 250 Ohms to ground is 20 mA (pins are rated for 24 mA
  • Schmitt Trigger Input
  • Input has single buffer stage
  • 3.3V, 250 Ohm resistors (/5) for 50 Ohm output
    • Normal output = 10 mA per pin

Test

  • Supply Vcc 3.3V to 5V and ground
  • Input is pulled up to Vcc
  • Measure output with BNC T
    • Should be 1/2 of Vcc with 50 Ohm terminator
    • Should be Vcc without terminator

Mechanicals

DRIVE50 MECHS REV1.PNG

Assembly Sheet