sheldon
|
Jovial,
A value of 450 MegaOhms is a very large value to try to integrate. Typical diffused and poly silicon resistors have relatively low sheet resistances, which implies long, thin resistors. Not sure what value of sheet resistance the process has. However, even assuming a very high sheet resistance of 10kOhm/sq, means that the resistor would require 45,000 squares to realize. In addition, to the resistor, you will probably need guard rings around the resistor to prevent leakage further increasing the area. BTW, the 10kOhm/sq assumes the process has a pinched resistor which means that there is a very limited voltage range of operation for the resistor. More practical diffused and poly resistors have sheet resistances on the order of ~100 Ohms/sq. Which implies ~1M squares of resistance. Loose Electron is correct, a design requiring a 450MOhm resistor implies that the design is not appropriate for integration.
Best Regards,
Sheldon
|