Cypress CapSense CY8CMBR2044, Design Manual

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Low-Power Design Considerations
AN66308 - CY8CMBR2044 CapSense® Design Guide, Doc. No. 001-66308 Rev. *F 35
Average Current in NO TOUCH State (I
AVE_NT
)
Equation 8
Where:
T
R
= Button Scan Rate
T
S
= Scan time
I
SLEEP
= current consumed by CY8CMBR2044 during low power sleep mode, from Table 5-2
I
ACTIVE
= current consumed by CY8CMBR2044 during active operation, from Table 5-2
Average Current in TOUCH State (I
AVE_T
)
Equation 9
Where:
T
S
= Scan time
I
SLEEP
= current consumed by CY8CMBR2044 during low power sleep mode, from Table 5-2
I
ACTIVE
= current consumed by CY8CMBR2044 during active operation, from Table 5-2
Average Standalone Current (I
AVE_SA
)
Equation 10
Where
P = percentage of time CS is in the TOUCH state compared to total time CY8CMBR2044 is on
I
AVG_NT
= average current for in the NO TOUCH state
I
AVG_T
= average current in the TOUCH state
Average Current (I
AVE
)
Equation 11
Where:
T
SA
= time device is in standalone mode
T
DS
= time device is in deep sleep mode