QT118H-S ETC, QT118H-S Datasheet
QT118H-S
Related parts for QT118H-S
QT118H-S Summary of contents
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... QT118H continuously if desired. By using the charge transfer principle, the IC delivers a level of performance clearly superior to older technologies in a highly cost-effective package. - Appliance control Security systems AVAILABLE OPTIONS T SOIC +70 C QT118H +85 C QT118H-IS QProx™ QT118H -T T HARGE RANSFER OUCH ...
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... The QT switches and charge measurement hardware functions are all internal to the QT118H (Figure 1-3). A 14-bit single-slope switched capacitor ADC includes both the required QT charge and transfer switches in a configuration that provides direct ADC conversion. The ADC is designed to ...
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... Figure 1-5), which is more than two orders of magnitude greater than that required to create a return path to the QT118H via earth. The QT118H's PCB however can be physically quite small, so there may be little ‘free space’ coupling (Cx1 in Figure 1-5) between it and the environment to complete the return path ...
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... S ENSITIVITY The QT118H can be set for one of 3 gain levels using option pin 5 (Table 1-1). This sensitivity change is made by altering the internal numerical threshold level required for a detection. Note that sensitivity is also a function of other things: like the value of Cs, electrode size, shape, and ...
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... As the basic burst spacing is 75ms, if this spacing was maintained throughout all 4 counts the sensor would react very slowly. In the QT118H, after an initial detection is sensed, the remaining three bursts are spaced about 18ms apart, so that the slowest reaction time ...
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... Option strap configurations are read by the QT118H only on powerup. Configurations can only be changed by powering the QT118H down and back up again; a microcontroller can directly alter most of the configurations and cycle power to put them in effect. ...
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... O D UTPUT RIVE The QT118H’s `output is active high and it can source 1mA or sink 5mA of non-inductive current. Care should be taken when the IC and the load are both powered from the same supply, and the supply is minimally regulated. The device derives its internal references from the power supply, and sensitivity shifts can occur with changes in Vdd, as happens when loads are switched on ...
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... DMM. Repeat the test without a load to measure the capacitor's internal leakage, and subtract the internal leakage result from the voltage droop measured during the QT118H load test. Be sure the DMM is connected only at the end of each test, to prevent the DMM's impedance from contributing to the capacitor's discharge. ...
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The circuit is remarkably immune to HF RFI provided that certain design rules be adhered to: 1. Use SMT components. 2. Always use a ground plane under the circuit. 3. Use a 0.1uF bypass cap very close to the supply ...
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ABSOLUTE MAXIMUM SPECIFICATIONS Operating temp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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DC SPECIFICATIONS Vdd = 3.0V 10nF 5pF, T Parameter Description DD DD DDS Preliminary Data: All specifications subject to change. Figure 4-1 - Typical Threshold Sensitivity vs. ...
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SYMBOL Min a 6.096 A 7.62 M 9.017 m 7.62 Q 0.889 P 0.254 L 0.355 L1 1.397 F 2.489 R 3.048 r 0.381 S 3.048 7.62 x 8.128 Y 0.203 SYMBOL Min M 4.800 W 5.816 ...
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... ORDERING INFORMATION PART QT118H-D QT118H-S QT118H-IS Quantum Research Group Ltd. TEMP RANGE 0 - 70C 0 - 70C -40 - 85C www.qprox.com Capstan House, High Street Hamble, Hants SO31 4HA United Kingdom US: +1 (412) 391-7367 UK: +44 (0)23 8045 3934 fax: +44 (0)23 8045 3939 QProx is a trademark of QRG Ltd. PACKAGE ...