Other Parts Discussed in Thread: LDC3114
Using the LDC Tools Coil Calculator Excel spreadsheet, rev1.50, I filled out the Spiral_Inductor_Designer with known application parameters then moved on to the LDC3114_Config_tool tab. I have some questions on that tab.
1. The "Estimated Current in NP" was higher than I anticipated. Does that calculation include just one sensor active, or two sensors active? I check "Enable Ch2" (to make 3 sensors active) and nothing changes for Estimated Current. I try to uncheck "Enable Ch1" and I get an error message, "The cell or chart you're trying to change is on a protected sheet. To make a change, unprotect the sheet. You might be requested to enter a password." So I cannot examine the Estimated Current with only one channel enabled. Should I estimate it by halving the Normal Power Scan Rate?
2. Since the spreadsheet has hidden cells and is protected, I cannot determine how the estimated current is calculated. As mentioned, it is higher than I would like it to be. What parameters should I change in the coil design in order to have lower current? Should I be focusing on Rp, or inductance, or something else?
3. Are there any rules of thumb for current draw based on coil size? e.g. Will a racetrack tend to have more or less current draw then a same diameter circular coil? Will 2 small coils in a given area be more or less efficient than one large coil? Can you point me to any design guidelines with a focus on current draw?
Thank you.