Dear Kai,

Thank you so much for your valuable time you have spent drawing the layouts for me. I have modified my board layout as per your recommendations and posting the new layouts for further recommendations / approval. I am very poor when it comes to analog and still have some silly doubts, Please reply and clear the doubts.

1. In your original schematic the 64Hz square wave output from CD4060 is connected like this..

CD4060 --->39k --->47uF

Where as in your layouts that you posted in recent post shows other way ie.
Oscillator --> 47uF ---> 39k

Whats the correct way or it doesnt matter either ways correct?

2. You had suggested filtering each and every supply signal using a 100E Resustor 47uF aluminum electrolytic and 100nF. But in your layout there are two resistors. I have accordingly split that 100E into two 47E resistors is it OK?

3. Is the placement of oscillator section correct or it needs to be moved upwards towards the power input connector? I thought this because moving it upward will reduce the path length of noisy digital section ground returns which flows through analog section while returning to connector. Am i correct?

4. I remember some time back you had suggested that Analog and Digtial ground planes should meet at one and only one point. But in case of layout you posted the two planes are joined at two places ie. top layer as well as bottom layer.

Here are the corrected layouts..




Thanks & Regards,
Prahlad Purohit