2.Diode Bridge Simulation one

First step - redrawing the circuit, helped me to understand the function.

I tried to simulate the circuit, it was much more difficult than excepted.

  • Diode bridge operates like a fast differential amplifier, connected as comparator. Base-Q2 has a constant DC voltage.
  • Q1 switched byTrigger Puls ON or OFF.
  • After switching ON, diode network (D5, D6, D3, D4) shifts "signal-bridge-in"  to "bridge-out".
  • Diode network is placed between both differential amplifier outputs.
  • Current mirror Q3, Q4 set constant current.
  • DC-baseline set amplifier current and offset.
  • "Skew" and "AC -bal", amplifier frequency compensation network for an equal switching between ON and OFF condition.

A tricky circuit. Scope photos in AN74 show only small switching transients - almost unbelieveable. In the simulation I could not reach good adjustmensts for "AC-bal" and "skew". 

High switching transients. It seems this simulation can't be compared in detail with a real circuit.


Impressum und Haftungsausschluss