qt118h Quantum Research Group, qt118h Datasheet - Page 9

• Manufacturer Part Number: qt118h
• Description: Charge-transfer Touch Sensor
• Manufacturer: Quantum Research Group

4.1 ABSOLUTE MAXIMUM SPECIFICATIONS
Operating temp. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . as designated by suffix
Storage temp. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55
V
Max continuous pin current, any control or drive pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±20mA
Short circuit duration to ground, any pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . infinite
Short circuit duration to V
Voltage forced onto any pin. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.6V to (Vdd + 0.6) Volts
4.2 RECOMMENDED OPERATING CONDITIONS
V
Short-term supply ripple+noise. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±5mV
Long-term supply stability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±100mV
Cs value. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10nF to 500nF
Cx value. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 to 100pF
Rs value. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 470K✡
4.3 AC SPECIFICATIONS
Vdd = 3.0, Cs = 10nF, Rs = 470K, Cx = 10pF, Gain = High, Ta = 20
4.4 SIGNAL PROCESSING
Vdd = 3.0, Cs = 10nF, Rs = 470K, Cx = 10pF, Gain = High, Ta = 20
Note 1: Pin options
Note 2: Percentage of signal threshold
Note 3: Pin option
Note 4: Cs, Cx dependent
lq
Parameter
Description
Threshold differential
Hysteresis
Detect integrator filter length
Positive drift compensation rate
Negative drift compensation rate
Post-detection recalibration timer duration (typical min/max)
DD
DD
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.5 to +6.5V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +2.5 to 5.0V
T
T
T
T
T
T
T
F
T
F
RC
BS
PO
HB
BL
Q
R
P
Q
P
Recalibration time
Charge, transfer duration
Burst spacing interval
Burst length
Response time
Piezo drive frequency
Piezo drive duration
Pulse output width on Out
Heartbeat pulse width
Burst frequency
Description
DD
, any pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . infinite
Min
0.5
3.6
Typ
550
129
300
165
75
95
75
75
Min
2
4
10
9
6, 12, or 24
O
O
C, unless otherwise noted.
C, unless otherwise noted.
Typ
750
Max
17
75
4.4
4
50
Max
60
Units
kHz
kHz
ms
ms
ms
ms
ms
ms
ms
µs
µs
@ 5.0V Vdd
@ 3.3V Vdd
Depends on Cs, Cx
samples
ms/level
ms/level
counts
Units
secs
%
QT118H R1.08 / 0405
1
2
4
4
3, 4
Notes
Notes
O
C to +125
O
C