ACF2101: Regards to ACF2101 IC application

Hi,

if you don't know when the input signal starts and stops and if you cannot gain a trigger signal from the input signal itself, then the only way is to gain a suited signal by observing the output of integrator.

Kai

Hi Gowtham,

Kai is correct, if you cannot predict when the input signal will become active you can monitor the output voltage of the ACF2101 to determine if an input signal is present. This will require you to operate in integrate mode while waiting for an expected input signal. If the input signal is inactive for a very long period of time, you may need to reset your integrator due to the effects of droop on the integrator's output voltage. Please refer to Page 11 of the ACF2101 datasheet for a detailed explanation of droop in the ACF2101.

The hold function disconnects the input signal from the integrating capacitor to hold the accumulated charge and prevent the output of the ACF2101 from exceeding its output swing. Depending on the magnitude and pulse width of your input signal, the hold function may not be necessary if your input signal goes inactive before the output swing is violated. For example, if the input signal charges the integrator to -8V and then goes inactive, the integrator will hold the -8V (with the effects of droop) until the integrator is reset or the input current becomes active again.

Thanks,

Zach