Cypress CYALKIT-E02, Reference Design Kit Manual

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Reference Design
CYALKIT-E02 Solar-Powered BLE Sensor Beacon Reference Design Kit Guide, Doc. No. 002-11317 Rev. *C 55
Timer Mode (TM)
CIN1
CIN0
CIN2
ON OFF
ON OFF ON
OFF
T0
T1
T2 T2
OFF
OFF
OFF
VOUT1
START
START
STOP
RESET STOP
RESET
STOP
RESET STOP
RESET
STOP
RESET
START
START
START
START
T0
T1
ON
VSTORE1
VSTORE2
VOUT2
Not used
5.1.4.2 Setting of Timer
The timer times 0, 1, and 2 (T0, T1, and T2) are set according to the capacitance value at the connections between the CIN0,
CIN1, and CIN2 pins and the AGND pin.
The values of timer 0 (T0), timer 1 (T1), and timer 2 (T2) can be calculated using the following formulas.
T0[s] = 0.5455×C[F]×10^9 + 0.01327[s] = 0.5455×220×10^
–12×10^9 + 0.01327[s] =
0.13 [s]
T1[s] = 0.5455×3.77×10^-9×10^9 + 0.01327[s] = 2.07 [s]
T2[s] = 0.5455×2.2×10^
–9×10^9 + 0.01327[s] =
1.21 [s] (Demo mode)
T2[s] = 0.5455×570×10^
–9×10^9 + 0.01327[s] =
310 [s] (Timer mode)
5.1.5 Unused Pins
Table 5-4 lists the unused pins.
Table 5-4. Description of Unused Pins
Pin Name Description
COMPP
Open
Comparator input pin
COMPM
Open
Comparator input pin
VOUT2
Open
Output voltage pin
VIN_LDO
Connect GND
LDO power input pin
VOUT_LDO
Open
LDO output pin
FB_LDO
Open
LDO output voltage setting pin
SW_CNT/CMPOUT
Open
VOUT1 switch interlocking output pin/comparator output pin
1
2
3
4
Repeat