Hi there, Happy Holidays.
I would need some help with attached project because I am not analog designer.
The point is that I cannot get a aproximately flat range of frequencies required with a flat gain.
I need a aproximately flat response from 500 Hz to 10,000 Hz .may be there are other solution I do not Know .
The facts are these:
The Gain is set to 4.3 or 12.7 db
Vin is 55 mv p-p. sinusoide and keeps constant.
Under 500 hz the behavior is the espected, I mean the gain increase as frecuency increase.
Over 500 or 600 Hz the gain reach the espected 12,7db but it does increase as frecuency increase to big
values, I mean much more than 12.7 db .
Near ,6000 or 7,000 hz there is a marked distortion.
Above aprox 7000 Hz the gain keeps incresing and also the distortion.
Based on : GBW = 3 MHZ and G = 4.3 the espected BW should be around +/- 20% of 698 KHZ. but that is not obtained.
The following table list readings from Rigol DS1102D scope using the whole sreen amplitud for reading volt values.
Hz mv P-P
300 36
1000 96
3000 275
6000 622
6500 1320
Above these frequencies the waveform is totally distorted and the V p-p increase up to the rail.
Thank you very much for any Help.
