qt114 Quantum Research Group, qt114 Datasheet
qt114
Related parts for qt114
qt114 Summary of contents
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... Its threshold levels are fixed, and the amount of signal required to exceed a threshold is dependent on circuit gain and electrode size and loading, all of which are under the control of the designer. The QT114 requires only a single inexpensive capacitor in order to function. One or two LEDs can also be added to provide a visual sensing indication. ...
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... Only a single external capacitor is required for operation. Figure 1-1 shows a basic QT114 circuit using the device, with conventional OUT drives and power supply connections. The sensing electrode can be connected to a single-tier or 2-tier electrode as required ...
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... Spiral wire probes are most effective in water-based fluids; they are not as effective in oils and other nonconductive substances. 3 Signal ignal Signal ISC ROBES W P PIRAL IRE ROBES QT114 R1.04/1106 Level l 2 Level l 2 Level ...
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... This applies to all probe types described above. Bare probes can also be used with aqueous fluids, but in these cases a 1,000pF (1nF) ceramic NPO capacitor should be inserted between the probe and the QT114 to block DC current flows. 4 QT114 R1.04/1106 ...
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... When the strip or plateau is ‘covered’ with fluid the IC will detect on at least the OUT1 line; OUT2 can be ignored. 5 Figure 2-11 Twin-Level Coaxial Probes For Non-Aqueous Fluids , C F ISCOUS ONDUCTIVE ILMS QT114 R1.04/1106 ...
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... Cs. Selecting an appropriate value of Cs for a given electrode geometry is essential for solid detection stability. The QT114 employs dual threshold points set at 250 and 150 counts of acquisition signal. The signal travels in a reverse direction: increasing Cx reduces the signal counts result, 250 counts of signal corresponds to the most sensitive or ‘ ...
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... Cx loading until each OUT line activates in turn. FILT should be off to speed up response during testing. The QT114's internal clock is dependent on Vcc result, the threshold points in terms of delay time from the start of the burst are also substantially dependent on Vcc, but they are always fixed in terms of signal counts ...
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... If the sensor is wired to a microprocessor as shown in Figure 3-3, the microprocessor can reconfigure the load resistor to either ground or Vcc depending on the output state of the QT114, so that the pulses are evident in either state with either POL setting. GATE OR MICRO INPUT ...
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... If the QT114 is connected to an external circuit via a long cable possible for ground-bounce to cause damage to the OUT pins; even though the transients are led away from the QT114 itself, the connected signal or power ground line will act as an inductor, causing a high differential voltage to build up on the OUT wires with respect to ground ...
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... Min Typ Max 250 150 3 15 190 +125 Units Notes µs µ counts ms Slosh filter disabled µ 5pF 5pF µs Units Notes counts Note 1 counts Note 1 counts Note 1 seconds Note 2 counts Note 1 QT114 R1.04/1106 O C ...
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... Notes Units V µA V/s Required for proper startup V FILT, POL V FILT, POL V OUT1, OUT2, 5mA sink V OUT1, OUT2, 1mA source µA FILT, POL pF pF/count Cs = 20nF 10pF pF/count Cs = 20nF 30pF FIGURE 4-2 Signal Level vs. Cx Load 20nF; Vcc = 3 0.00 10.00 20.00 Cx Load, pF QT114 R1.04/1106 30.00 40.00 ...
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... Min Max 0.24 0.28 0.3 0.325 0.355 0.43 0.3 0.3 0.035 - 0.01 - 0.014 0.022 0.055 0.065 0.098 0.102 0.12 0.15 0.015 - 0.12 0.14 - 0.16 0.3 0.3 0.32 0.39 0.008 0.015 Inches Min Max 0.189 0.196 0.229 0.244 0.15 0.157 0.054 0.068 0.004 0.01 0.050 0.05 0.014 0.019 0.02 0.04 0.007 0.01 0.229 0.03 0º 8º QT114 R1.04/1106 Notes Typical BSC Typical BSC Notes BSC ...
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... ORDERING INFORMATION PART QT114-DG QT114-ISG 6 MOISTURE SENSITIVITY LEVEL (MSL) MSL Rating MSL1 LQ TEMP RANGE PACKAGE PDIP 0 - 70C Lead-Free SOIC-8 -40 - 85C Lead-Free Peak Body Temperature O 260 C 13 MARKING QT114 or QT114-DG QT114 or QT1G Specifications IPC/JEDEC J-STD-020C QT114 R1.04/1106 ...
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Tel: +44 (0)23 8056 5600 Fax: +44 (0)23 8045 3939 The specifications set out in this document are subject to change without notice. All products sold and services supplied by QRG are subject to QRG’s Terms and Conditions of ...