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CY4636 WirelessUSB™ LP Keyboard Mouse Reference Design Kit User Guide, Doc. # 001-70355 Rev. *A
Table A-6. Keyboard Current Measurement
A.6.1.3
Battery Life Calculations
The following table shows the times spent in each state by the RDK keyboard usage model. By sub-
stituting the current measurements in section Current Measurements, the overall average Icc for
RDK keyboard can be calculated.
Table A-7. RDK keyboard Power Consumption
The RDK keyboard uses two AA cells and enables the PMU function. Therefore, it is able to access
approximately 2850-mAh battery capacity, which yields a battery life estimate of 829 days or 27
months.
A.6.2
RDK Mouse
A.6.2.1
Usage Model
The following usage model is considered for the RDK mouse.
■
1 hour per day with the 3030/3040 sensor in 'active' state
■
2 hours per day with the 3030/3040 sensor in 'rest1' state
■
2 hours per day with the 3030/3040 sensor in 'rest2' state
■
19 hours per day with the 3030/3040 sensor in 'rest3' state
■
5 days per week as above, 2 days per week 24 hours in 'rest3' state
Operation Mode
Icc (mA) with Supply
Voltage = 2.5 V
Icc (mA) with Supply
Voltage = 2.8 V
Average Icc (mA)
Active state - Place the key-
board in test mode "the
quick brown fox …" and set
the typing rate to 8 key-
strokes per second.
0.96
0.83
0.90
Idle state - A keyboard is in
its normal power on state
and connected to the bridge
with no keys pressed.
0.04
0.04
0.04
Not connected state - Type
the keyboard.
20.3
16.9
18.6
Not connected state - No
typing.
Transition to idle state.
Transition to idle state.
State
Hours/day
Days
Average Icc
(mA)
Charge
(mAh)
Week day
Active
4
5
0.90
18
Idle
20
5
0.041
4.1
Weekend
Idle
24
2
0.041
1.97
Charge Per Week (mAh)
24.07
Overall Average Icc (mA)
0.143
