alok_ky
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If you read some transmission line theory, you'll come across two formulas for transmission line propagation delays.
Specifically for microstrip line :
1) Tpd = sqrt(LC)
where L and C are inductance and cap. of the tx line per inch.
2) Tpd = 85*sqrt(absilon_r)
where absilon_r : relative permittivity of the material.
Why there are two different formulas ?
In the first formula, the delay depends upon the L and C of the line.
But in the second, it looks independent of the line parasitics (L & C)
Can anybody give explanation ?
Added after 1 minutes:
To modifiy the query, the above formulas hold for strip line type of tx line rather than micro-strip tx line.
Specifically for microstrip line :
1) Tpd = sqrt(LC)
where L and C are inductance and cap. of the tx line per inch.
2) Tpd = 85*sqrt(absilon_r)
where absilon_r : relative permittivity of the material.
Why there are two different formulas ?
In the first formula, the delay depends upon the L and C of the line.
But in the second, it looks independent of the line parasitics (L & C)
Can anybody give explanation ?
Added after 1 minutes:
To modifiy the query, the above formulas hold for strip line type of tx line rather than micro-strip tx line.