tle4941, tle4941c tle4941 - tle4941c data sheet february 2002 1 appendix b release 1.0 1. occurrence of initial calibration delay time t d,input if there is no input signal (standstill), a new initial calibration is triggered each 0.7s. this calibration has a duration t d,input of max. 300s. no input signal change is detected during that initial calibration time. in normal operation (signal startup) the probability of t d,input to come into effect is: t d,input / time frame for new calibration 300s/700ms = 0,05%. after ic resets (e.g. after a significant undervoltage) t d,input will always come into effect. 2. magnetic input signal extremely close to a switching threshold of pga at signal startup: after signal startup generally all pga switching into the appropriate gain state happens within less than one signal period. this is included in the calculation for n dz-start . for the very rare case that the signal amplitude is extremely close to a pga switching threshold and the full range of following speed adc respectively, a slight change of the signal amplitude can cause one further pga switching. it can be caused by non-perfect magnetic signal (e.g. amplitude modulation due to tolerances of pole-wheel, tooth wheel or air gap variation). this additional pga switching can result in a further delay of the output signal (n dz-start ) up to three magnetic edges leading to a worst case of n dz-start =9. due to the low probability of this case it is not defined as max. value in the data sheet. (for a more detailed explanation please refer to the document "tle4941/42 - frequently asked questions").
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