Quantum Research Group Ltd.
4 August 2004
QT112-I / QT112H-I QProx™ 8-pin Sensor
See QT110 datasheet for primary information. This sheet only lists differences with the QT110.
This part is only available in -I suffix (-40..+85C)
Description
The QT112 is a variant of the QT110 having a faster response time of 49ms worst case, and 25ms typical. It is
designed for those touch sensing applications where faster speed is paramount, for example in games and toys
where rapid reaction time is critical, or in machine tool controls where speed is important. It trades off power
consumption for speed. Also, note that the device has a consensus filter count 2 instead of 4, and does not have
an acoustic driver for a piezo 'beeper'.
Differences with the QT110
The QT112 sensor is exactly the same in all respects to the QT110 with the following exceptions (refer to Tables
4.3, 4.4, and 4.5 in the QT110 datasheet):
4.3 AC SPECIFICATIONS Vdd = 3.0, Ta = recommended operating range
Description
Min
Typ
Max
Units
Parameter
Notes
T
BS
Burst spacing interval
Response time
24
49
ms
ms
T
R
4.4 SIGNAL PROCESSING
Description
Min
Max
Units
Typ
2
1,250
24
Notes
Consensus filter length
samples
ms/level
ms/level
Positive drift compensation rate
Negative drift compensation rate
4.5 DC SPECIFICATIONS
Vdd = 3.0V, Cs = 10nF, Cx = 5pF, Ta = recommended range, unless otherwise noted
Parameter
Notes
Description
Supply current
Min
Typ
Max
Units
I
DD
60
µA
Piezo Driver Note: The piezo acoustic driver has been removed, as the duration required to operate the
beeper would interfere with the sensing interval and slow down the device.
QT112H Version
The QT112H version is the same as the QT112 except with an active-high output.
All other operating modes, specifications, and wiring should be taken from the QT110 data sheet.
Package Marking - QT112-I
DIP Package: DIP devices are marked 'QT112'
SO8 Package: Marked 'QT1 2I'
Package Marking - QT112H-I
DIP Package: DIP devices are marked 'QT112H'
SO8 Package: Marked 'QT1 M'
QT112 QProx™ 8-pin Sensor
© 1999 QRG Ltd.
QUANTUM [ QUANTUM RESEARCH GROUP ]
