[sdiy] Pro One CEM3340 Sync magic

[Simon Brouwer]

Op 18-4-2010 19:45, ASSI schreef:
> On Sunday 18 April 2010, Simon Brouwer wrote:
>    
>> Can somebody explain how this should work? Note that a sync pulse
>> pulls the triangle buffer *output* down. After the pulse,
>> the voltage on the integrator capacitor will not be reset but will
>> be roughly the same value as before it (if the free running period
>> is large compared to the sync pulse).
>>      
> How can you make such a statement without knowing how that buffer is
> realized?
>    
I assumed an opamp-type buffer. I cannot be expected to have the 
detailed knowledge of
the implementation that you have.

> In fact that thing shown as "BUF" in the datasheet is an emitter
> follower followed by a Darlington emitter follower, so if you pull the
> output down with a low enough impedance, the bases will all have to go
> down as well, with three diode drops inbetween.
>    
I see now. Thanks!

-- 

Vriendelijke groet,
Simon Brouwer.

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