Method and circuit arrangement for determining the average current consumption of a battery-operated apparatus

1. A circuit arrangement for determining the average current consumption of a battery-operated electronic apparatus, characterized in that a switching element (S) is positioned between an energy source ( 3 ) and the apparatus ( 1 ), and In that an energy store (C) is provided which is chargeable from the energy source ( 3 ) across the switching element (S) and which is dischargeable across the apparatus ( 1 ), in that a comparator assembly ( 4 ) determines the charging state of the energy store (C), the comparator assembly ( 4 ) switching the switching element (S) to the non-conductive state if the predetermined upper threshold value (Uso) is exceeded and switching the switching element (S) to the conductive state if the lower threshold value (Usu) is fallen below, the energy store (C) being charged when the switching element (S) is in the conductive state and discharged across the apparatus ( 1 ) in accordance with the respective current consumption thereof when the switching element (S) is in the non-conductive state, and in that a counter ( 8 ) is provided, which counts the number (N) of charging and/or discharging processes occurring within the predetermined measuring time (T), and in that a computing unit ( 10 ) is provided which calculates the average current consumption from the number (N), the measuring time (T) and the determined size of the energy store (C) as well as with the upper threshold value (Uso) and the lower threshold value (Usu).

2. A circuit arrangement as claimed in claim 1 , characterized in that the energy store is a capacitor.

3. A circuit arrangement as claimed in claim 2 , wherein the capacitance of the capacitor amounts to approximately 5 mF to approximately 40 mF.

4. A circuit arrangement as claimed in claim 1 , wherein the measuring time (T) amounts to from 1 s to 45 s, the capacitance of the capacitor (C) being so high that in the case of a typical operating sequence a plurality of charging and discharging processes occur during the measuring time (T).

5. A circuit arrangement as claimed in claim 1 , wherein the upper threshold value lies between approximately 4.2 V and approximately 3.6 V and the lower threshold value lies approximately between 3.5 V and approximately 3.0 V.

6. A circuit arrangement for determining the average current consumption of a battery-operated electronic apparatus, comprising:

a switching element positioned between an energy source and the apparatus;

an energy store, wherein the energy store is chargeable from the energy source across the switching element and is dischargeable across the apparatus;

a comparator assembly adapted to determine a charging state of the energy store, the comparator assembly switching the switching element to the non-conductive state if the predetermined upper threshold value is exceeded and switching the switching element to the conductive state if the lower threshold value is fallen below, the energy store being charged when the switching element is in the conductive state and discharged across the apparatus in accordance with the respective current consumption thereof when the switching element is in the non-conductive state;

a counter operative to count a number of charging and/or discharging processes occurring within the predetermined measuring time; and

a computing unit adapted to calculate an average current consumption from the number, the measuring time, a determined size of the energy store, the upper threshold value and the lower threshold value.

7. A circuit arrangement as claimed in claim 6 , wherein the energy store is a capacitor.

8. A circuit arrangement as claimed in claim 7 , wherein the capacitance of the capacitor amounts to approximately 5 mF to approximately 40 mF.

9. A circuit arrangement as claimed in claim 7 , wherein the measuring time amounts to from 1 s to 45 s, the capacitance of the capacitor (C) being so high that in the case of a typical operating sequence a plurality of charging and discharging processes occur during the measuring time (T).

10. A circuit arrangement as claimed in claim 6 , wherein the upper threshold value lies between approximately 4.2 V and approximately 3.6 V and the lower threshold value lies approximately between 3.5 V and approximately 3.0 V.