lQ
C
HARGE
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RANSFER
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OUCH
S
ENSOR
QProx™ QT118H
Less expensive than many mechanical switches
Projects a ‘touch button’ through any dielectric
100% autocal for life - no adjustments required
No active external components
Piezo sounder direct drive for ‘tactile’ click feedback
LED drive for visual feedback
2.5 ~ 5V single supply operation
10µA at 2.5V - very low power drain
µ
Toggle mode for on/off control (via option pins)
10s or 60s auto-recalibration timeout (via option pins)
Pulse output mode (via option pins)
Gain settings in 3 discrete levels
Simple 2-wire operation possible
HeartBeat™ health indicator on output
Pb-Free package
Vdd
Out
Opt1
Opt2
1
8
Vss
Sns2
Sns1
Gain
QT118H
2
3
4
7
6
5
APPLICATIONS -
Light switches
Industrial panels
Appliance control
Security systems
Access systems
Pointing devices
Elevator buttons
Toys & games
The QT118H charge-transfer (“QT’”) touch sensor is a self-contained digital IC capable of detecting near-proximity or touch. It will
project a sense field through almost any dielectric, like glass, plastic, stone, ceramic, and wood. It can also turn small metal-bearing
objects into intrinsic sensors, making them respond to proximity or touch. This capability coupled with an ability to self calibrate
continuously can lead to entirely new product concepts.
The device is designed specifically for human interfaces, like control panels, appliances, toys, lighting controls, or anywhere a
mechanical switch or button may be found; it may also be used for some material sensing and control applications provided that the
presence duration of objects does not exceed the recalibration timeout interval.
A piezo element can also be connected to create a feedback click sound.
The IC requires only a common inexpensive capacitor in order to function. Average power consumption is under 20µA in most
applications, allowing battery operation.
The QT118H employs digital signal processing techniques pioneered by Quantum, designed to make it survive real-world
challenges, such as ‘stuck sensor’ conditions and signal drift. Sensitivity is digitally determined for the highest possible stability. No
external active components are required for operation.
The device includes several user-selectable built in features. One, toggle mode, permits on/off touch control, for example for light
switch replacement. Another makes the sensor output a pulse instead of a DC level, which allows the device to 'talk' over the power
rail, permitting a simple 2-wire twisted-pair interface. Quantum’s unique HeartBeat™ signal is also included, allowing a host
controller to continuously monitor the health of the device.
By using the charge transfer principle, the IC delivers a level of performance clearly superior to older technologies in a highly
cost-effective package.
0 C to +70 C
-40
0
C to +85
0
C
0
T
A
0
AVAILABLE OPTIONS
SOIC
-
QT118H-ISG
8-PIN DIP
QT118H-DG
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©1999-2004 Quantum Research Group
R1.08 / 0405
QUANTUM [ QUANTUM RESEARCH GROUP ]
