qt60160 Quantum Research Group, qt60160 Datasheet - Page 24

• Manufacturer Part Number: qt60160
• Description: 16 And 24 Key Qmatrix Touch Sensor Ics Research Group
• Manufacturer: Quantum Research Group

7.5 Power Consumption
The formula to find the average current is:
Example: Conditions: Vdd = 1.8V, 10 keys BL = 32, 14 keys BL = 16, Tsleep = 125ms

Where:
Idd
Idds
Tsleep
Iddr
T
KE
1
BS
if more than one burst spacing is used then each must be
included in the calculation.
Idd = (current sleeping x sleep period) + (current running x (burst spacing x number of keys enabled))
Idd = (Idds x Tsleep) + (Iddr x (T
Idd = (0.003 x 125) + (1.02 x ((0.38 x 10) + (0.27 x 14))) = 0.06115mA = 61.15µA
=
=
=
=
=
=
average current (mA)
current when sleeping
sleep period
current when running
burst spacing
number of keys enabled
Tsleep + (T
Test condition: BL = 48, 16 or 24 keys enabled (see appropriate column)
125 + ((0.38 x 10) + (0.27 x 14))
Voltage (V)
(
sleep period + (burst spacing x number of keys enabled)
1
ms
Table 7.1 Average Current Consumption
(ms)
BS
1.8
3.3
5.0
1.8
3.3
5.0
1.8
3.3
5.0
1.8
3.3
5.0
1.8
3.3
5.0
1.8
3.3
5.0
1.8
3.3
5.0
1.8
3.3
5.0
)
x KE)
(
mA
(
BS
mA
1
x KE))
)
)
Setting (ms)
Sleep
1000
2000
125
250
500
(Section 7.3)
(Table 6.2)
(Section 7.3)
(Section 7.4)
16
32
64
24
Note: there may be more than one inst ance of (T
24 keys
(see example below)
Idd Typical (mA)
0.480
1.050
1.900
0.300
0.670
1.220
0.170
0.350
0.730
0.090
0.220
0.400
0.050
0.120
0.240
0.043
0.090
0.160
0.040
0.080
0.130
0.039
0.075
0.120
16 keys
0.360
0.840
1.550
0.250
0.540
0.910
0.150
0.310
0.550
0.080
0.170
0.300
0.048
0.100
0.160
0.040
0.060
0.110
0.038
0.053
0.100
0.037
0.050
0.095
QT60240-ISG R8.06/0906
BS
x KE)