qt301 ETC-unknow, qt301 Datasheet
qt301
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qt301 Summary of contents
Page 1
... The PWM range is set via two inputs that control the starting and ending point of the conversion range. For example, if the capacitance range from 27pF to 38pF, the QT301 can be calibrated so that the PWM zero point occurs at 27pF, and the endpoint (255) occurs at 38pF. In this way, the PWM range is optimized for the zone of interest. These calibration points are stored in internal EEPROM and do not have to be reacquired after a power reset ...
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... R2 4 1.2 Basic Circuit Figure 1-1 shows a basic circuit diagram for the QT301. The pin layout of the QT301 is as explained in Table 1-1. In this particular circuit, C1 should be 100nF and R1, R2 and R3 should all be 10K only required if the synchronization feature is not used and can be connected to either VDD or VSS. ...
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... Sync pulses are spaced less than 100ms apart. Figure 2-2 shows the acquisition burst in relation to Sync pulses rising edge is detected for 100ms, the QT301 will revert to the default timing shown in Figure 2-1. Figure 2-4 shows the sudden start of a train of Sync pulses and the effect on the acquisition bursts ...
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... Vdd. Hold this level high for 2.5ms minimum (preferably, 3ms to be safe). Then release the pin to try to float down. The QT301 will continue to hold the pin high starting at the 2.5ms point. There should be no contention problem with an external voltage plus the QT301 both holding this pin high. ...
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... When the QT301 is done calibrating, it will release the CAL pin in question to float low. A host controller can use this feature to check when the calibration process has completed. Calibration takes 15 acquisition burst samples to complete. The new calibration data is stored in internal EEPROM when the host releases the CAL pin to float low again; the chip also begins to operate normally again at this time ...
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... T BS Min Typ Max 5 2.9 0.3 VDD 0.6 VDD 0.5 VDD-0 +125 Units Notes ms pF Units Notes µs kHz % +/-10% over voltage and temperature range ms ms kHz ms ms Units Notes mA @5V mA @3.3V V VDD = 3 to 5.5V V VDD = 6mA -1.5mA OH bits fF QT301 R1.04 21/09/ ...
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... VDD = 5.0 Volts LQ 200nF 120nF 80nF 40nF 5.0 4.5 4.0 3.5 3.0 2.5 2.0 2.5 3.0 3.5 4.0 Power supply, Volts Figure 6-3 Power Consumption versus VDD 7 1000 900 800 700 600 500 400 300 200 100 Load Figure 6-2 Typical Burst Length versus Cx & Cs; VDD= 5.0 Volts 4.5 5.0 5.5 QT301 R1.04 21/09/03 22nF 10nF 4.7nF 40 50 ...
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... LQ VDD = 5.0 Volts 10pF Temperature, °C Figure 6-5 Typical Signal Deviation vs. Temperature Vdd = 5.0 Volts 10pF 5nF - 200nF PPS Film Temperature 200nF PPS 100nF PPS 4.7nF PPS QT301 R1.04 21/09/03 ...
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... L2 L Inches Min Max 0.24 0.28 0.3 0.325 0.355 0.4 0.3 - 0.027 0.037 0.014 0.022 0.045 0.07 0.008 0.012 0.1 - 0.015 - 0.115 0.15 - 0.21 0.43 H φ h Inches Min Max 0.205 0.213 0.3 0.33 0.203 0.212 0.05 0.012 0.02 0.004 0.013 0.07 0.08 0.007 0.01 0.02 0.035 QT301 R1.04 21/09/ Notes Typical BSC e E Notes BSC ...
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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 our Terms and Conditions of ...