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I want to detect logic of the mains supply (230VAC, 50Hz) and feed the output of HCPL-3700 into ATmega16L. I read through the datasheet but could not understand how to calculate the resistor values. Does anyone have an idea of how to go about doing this?

EDIT 1

I am referring to application note on HPCL-3700, page 5 under AC Operation With No Filtering

Assuming 60% criterion, 230 x sqrt(2) x 60% is 195V. choosing closest whole value of 200V instead of 195V.

Rx = (V+ - VTH+) / ITH+ = (200V - 5.5V) / 2.5mA = 38.9 Kohms.

choosing round figure of 40 Kohms for Rx. I can use two 22 Kohm resistors.

Calculating power dissipation in 22 Kohm resistors P = (I*I) * R = (4.4mA * 4.4mA) * 22K (where 4.4mA is Iin) = 425.92 mOhms

So, choosing 22 Kohm resistors with 500mW power rating.

How does this answer look? I think I'm wrong because there are few things that still don't make sense.

I want to detect logic of the mains supply (230VAC, 50Hz) and feed the output of HCPL-3700 into ATmega16L. I read through the datasheet but could not understand how to calculate the resistor values. Does anyone have an idea of how to go about doing this?

EDIT 1

I am referring to application note on HPCL-3700, page 5 under AC Operation With No Filtering

Assuming 60% criterion, 230 x sqrt(2) x 60% is 195V. choosing closest whole value of 200V instead of 195V.

Rx = (V+ - VTH+) / ITH+ = (200V - 5.5V) / 2.5mA = 38.9 Kohms.

choosing round figure of 40 Kohms for Rx. I can use two 22 Kohm resistors.

Calculating power dissipation in 22 Kohm resistors 
P = (I*I) * R 
= (4.4mA * 4.4mA) * 22K (where 4.4mA is Iin) 
= 426 mW

So, choosing 22 Kohm resistors with 500mW power rating.

How does this answer look? I think I'm wrong because there are few things that still don't make sense.

I want to detect logic of the mains supply (230VAC, 50Hz) and feed the output of HCPL-3700 into ATmega16L. I read through the datasheet but could not understand how to calculate the resistor values. Does anyone have an idea of how to go about doing this?

EDIT 1

I am referring to application note on HPCL-3700, page 5 under AC Operation With No Filtering

Assuming 60% criterion, 230 x sqrt(2) x 60% is 195V. choosing closest whole value of 200V instead of 195V.

Rx = (V+ - VTH+) / ITH+ = (200V - 5.5V) / 2.5mA = 38.9 Kohms.

choosing round figure of 40 Kohms for Rx. I can use two 22 Kohm resistors.

Calculating power dissipation in 22 Kohm resistors P = (I*I) * R = (4.4mA * 4.4mA) * 22K (where 4.4mA is Iin) = 425.92 mOhms

So, choosing 22 Kohm resistors with 500mW power rating.

How does this answer look? I think I'm wrong because there are few things that still don't make sense.

I want to detect logic of the mains supply (230VAC, 50Hz) and feed the output of HCPL-3700 into ATmega16L. I read through the datasheet but could not understand how to calculate the resistor values. Does anyone have an idea of how to go about doing this?

EDIT 1

I am referring to application note on HPCL-3700, page 5 under AC Operation With No Filtering

Assuming 60% criterion, 230 x sqrt(2) x 60% is 195V. choosing closest whole value of 200V instead of 195V.

Rx = (V+ - VTH+) / ITH+ = (200V - 5.5V) / 2.5mA = 38.9 Kohms.

choosing round figure of 40 Kohms for Rx. I can use two 22 Kohm resistors.

Calculating power dissipation in 22 Kohm resistors P = (I*I) * R = (4.4mA * 4.4mA) * 22K (where 4.4mA is Iin) = 425.92 mOhms

So, choosing 22 Kohm resistors with 500mW power rating.

How does this answer look? I think I'm wrong because there are few things that still don't make sense.

I want to detect logic of the mains supply (230VAC, 50Hz) and feed the output of HCPL-3700 into ATmega16L. I read through the datasheet but could not understand how to calculate the resistor values. Does anyone have an idea of how to go about doing this?

I want to detect logic of the mains supply (230VAC, 50Hz) and feed the output of HCPL-3700 into ATmega16L. I read through the datasheet but could not understand how to calculate the resistor values. Does anyone have an idea of how to go about doing this?

EDIT 1

I am referring to application note on HPCL-3700, page 5 under AC Operation With No Filtering

Assuming 60% criterion, 230 x sqrt(2) x 60% is 195V. choosing closest whole value of 200V instead of 195V.

Rx = (V+ - VTH+) / ITH+ = (200V - 5.5V) / 2.5mA = 38.9 Kohms.

choosing round figure of 40 Kohms for Rx. I can use two 22 Kohm resistors.

Calculating power dissipation in 22 Kohm resistors P = (I*I) * R = (4.4mA * 4.4mA) * 22K (where 4.4mA is Iin) = 425.92 mOhms

So, choosing 22 Kohm resistors with 500mW power rating.

How does this answer look? I think I'm wrong because there are few things that still don't make sense.