[AMPS] Blow TL922

[measures]

>
>
>The zener diode can be replaced with a series of c. 7, 1A forward-biased
>diodes. Such an arrangement is much more rugged than a zener.
>
>And also poor regulation - Does it really matter ? 

The cathode current varies from c. 160mA to c. 1000mA.  The resultant <1v 
variation in forward drop across the diode string is not very significant 
compared to the approx 115v of driving signal.  

> If you are doing that you
>might as well just use a resistor

With a resistor, to obtain the needed 5v of bias with 160mA,  approx 31 
ohms of R would be called for.  With c. 1000mA in a 31 ohm resistor, the 
drop would be c. 31v.  

> as the bias is only a few volts and it
>will probably still be cleaner than the driver. 

31 is hardly a few 

> I suggest you use a low
>power zener and a transistor, or a programmable zener like the TL431 and a
>pass transistor. G3SEK might comment.
>
Can this arrangement withstand 50a glitches?

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