Hello,
I need a micropower quadrature encoder interface for a battery powered application. I noticed you offer a QEI as AN-CM-277. Can you tell me the practical current consumption of this device while it receives a 1 kHz quadrature signal with everything running on 3.3V rails? Better yet, what is the current over a range of input frequencies?
Thank you,
MikeN
Device:
Device Number:
AN-CM-277 (SLG46140)
MikeN,
Thank you for your appeal,
For your clarification, two high-frequency OSCs (2MHz and 25MHz) are Forced On in the design, so just the design will consume around 200uA since OSCs are continuously working. It is possible to disable the OSC when there is no need to monitor the input, which can decrease the current consumption to <1uA.
I've also applied the different frequencies to input PINs Encoder A and Encoder B at voltage 3.3V, please see the testing results:
1kHz - Total chip current consumption 212uA;
10kHz - Total chip current consumption 215uA;
50kHz - Total chip current consumption 220uA;
100kHz - Total chip current consumption 230uA;
1MHz - Total chip current consumption 363uA.
The result can vary with voltage/temperature. The conditions the rest input PINs: Encoder Z - LOW, nCS - LOW, SCK - LOW.
Best regards,
olehs