VR input: R9 and R15 useful or not?

[rusefi]

R9=R15 DNP = more sensitive

both R9 and R15 in place = lower signal level, possibly necessary for extremely hot sensors

Matthew Kennedy says: I have no data to support that they are required since the tle8888 has internal clamp diodes to prevent overvoltage so I might even go so far as to say that we should just remove them the tle8888 datasheet application diagrams don't mention having a resistor there I have no idea why we have them honestly

[jharvey]

Perhaps change the resistors for TVS diodes, that kicks in when above some voltage, then they don't attenuate when at low RPM. Very similar to the 8888's internal TVS, but on the other side of the current limiting resistors. The "VR Sensor Interface Input Clamping Voltage" is as low as 2V, and "VR Sensor Interface Input Clamping Current" is a max of 50mA. At 50mA and our 20k of resistors, that's OK for 1kV. We would really fail closer to 100V as it would jump around the resistors at that point. So perhaps we should change R15 for like a 100V TVS, and perhaps we change R9 for something like a 1V TVS.

[rusefi]

let's just DNP R9 and R15?

[rusefi]

it was decided not to populate R9 and R15

see also #178

[rusefillc]

0.5.2 was fabricated without R15 but with R9

i think that's similar to the R2 issue, we need to DNP R9 a bit more :) @jharvey

[rusefillc]

@Qwerty-OFF can you please make R15 DNP?

[Qwerty-OFF]