qt1081 Quantum Research Group, qt1081 Datasheet
qt1081
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qt1081 Summary of contents
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... This datasheet is applicable to all revision 1 chips The QT1081 is an improved, lower cost, simplified circuit version of the popular QT1080 sensor IC. The QT1081 is designed for low cost appliance, mobile, and consumer electronics applications. QTouch™ technology is a type of patented charge-transfer sensing method well known for its robust, stable, EMC-resistant characteristics. ...
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... QT1081_1R0.04_0307 9 10 ...
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... DI mechanism to dramatically reduce the probability of false detection due to noise. 1.2.8 Sync Mode The QT1081 features a Sync mode to allow the device to slave to an external signal source, such as a mains signal (50/60Hz), to limit interference effects. This is performed using the SYNC/LP pin. Sync mode operates by triggering two sequential acquire bursts, in sequence A-B from the Sync signal ...
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... The QT1081 has two different AKS groupings of keys, selectable via option resistors. These groupings are: AKS operates in two groups of four keys. AKS operates over all eight keys. These two modes allow the designer to provide AKS while also providing for shift or function operations. ...
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... Open Open or option resistor* Open Open or option resistor* Open Open or option resistor* Open Open or option resistor* Open or † † mode resistor † Open or mode resistor or option resistor* Open - Vdd or Vss Open Open Open Open Open Open Open Open Open QT1081_1R0.04_0307 † ...
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... Section 3.2. A typical value of Rb2 FAST-DETECT Off Enabled Off Off QT1081_1R0.04_0307 KEY 2 KEY 1 KEY 0 Rb1 Rb2 12K 22K 15K 27K CSS is 100nF. OUT_7 OUT_6 OUT_5 OUT_4 OUT_3 OUT_2 Binary coded OUT_1 ...
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... The required value of spread-spectrum capacitor Rb2 will vary according to the lengths of the acquire bursts, see Section 3.2. A typical value OUT_7 31 OUT_6 30 OUT_5 29 OUT_4 28 OUT_3 27 OUT_2 26 OUT_1 25 OUT_0 OUT_0 FAST-DETECT Enabled Off QT1081_1R0.04_0307 KEY 2 KEY 1 KEY 0 Rb1 Rb2 12K 22K 15K 27K CSS CSS is 100nF. ...
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... When full options are in use, the SYNC/LP pin function is selected according to the SL_0 and SL_1 resistor connections as given in Table 1.5. When the QT1081 is in sync mode the pin acts as a SYNC input; when the QT1081 mode the pin acts input. When simplified options are in use, the QT1081 is always in LP mode and the SYNC/LP pin acts input ...
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... Operation in low power mode is governed by the state of the LP input and whether at least one key has a confirmed touch. If the LP input constant low level, then the QT1081 will remain in full speed operation (20ms typical response time and normal power consumption Figure 2.2. ...
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... Max On-Duration: 60 seconds See Tables 1.6 and 1.7. 2.11 Unused Keys Unused keys should be disabled by removing the corresponding Cs, Rs, and Rsns components and connecting SNS pins as shown in the ‘Unused’ column of Table 1.1. Unused keys are ignored and do not factor into the AKS function (Section 2.7). 10 QT1081_1R0.04_0307 ...
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... Design Notes 3.1 Oscillator Frequency The QT1081’s internal oscillator runs from an external resistor network connected to the OSC and SS pins, as shown in Figures 1.1 and 1.2, to achieve spread-spectrum operation. If spread-spectrum mode is not required, the OSC pin should be connected to Vdd with an 18KΩ one percent resistor. ...
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... Both bursts together 180ms LP setting ms End of touch Units Notes @ Vdd = 5.0 @ Vdd = 4 Vdd = 3.3 @ Vdd = 2.8 @ Vdd = 3.3V; 340ms LP mode µA @ Vdd = 2.8V; 340ms LP mode @ Vdd = 3.3V µA @ Vdd = 2.8V V/s @ Vdd = 2. 7mA sink V 2.5mA source µA bits QT1081_1R0.04_0307 +125 +85 C ...
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... Threshold for decrease of Cx load 2 secs Time to recalibrate if Cx load has exceeded anti-detection threshold 6 samples Must be consecutive or detection fails 2 samples Must be consecutive or detection fails 10, 60, ∞ secs Option pin selected 2,000 ms/level Towards increasing Cx load 500 ms/level Towards decreasing Cx load 13 QT1081_1R0.04_0307 ...
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... Vdd=5V Vdd=4V Vdd=3.3V Vdd=2. 400.0 300.0 Vdd=5V Vdd=4V 200.0 Vdd=3.3V Vdd=2.8V 100 Vdd=5V Vdd=4V Vdd=3.3V Vdd=2. Rosc = 18KΩ; no spread-spectrum QT1081, average Idd (180ms optimized LP operation) 0 burst length (ms) QT1081_1R0.04_0307 Vdd=5V Vdd=4V Vdd=3.3V Vdd=2.8V 6 ...
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... Vdd=3.3V Vdd=2.8V 100 Vdd=5V Vdd=4V Vdd=3.3V Vdd=2. 240 230 220 210 200 190 180 170 160 2.5 4.5 5 5.5 4.5 5 5.5 15 QT1081, average Idd (180ms LP operation) 0 burst length (ms) QT1081 Response Time (180ms LP operation) 3 3.5 4 4.5 Vdd QT1081_1R0.04_0307 Vdd=5V Vdd=4V Vdd=3.3V Vdd=2. 5.5 ...
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... Dimension L1 represents terminal pull-back from the package edge. Where terminal pull-back exists, only the upper half of 0.02 0.05 the lead is visible on the package edge due to half etching of 0.25 0.32 the leadframe. - The corner tie bar is connected internally to the exposed 5.00 5.10 central pad. - 3.65 5.00 5.10 - 3.65 0.50 - 0.40 0.50 - 0.075 - 0.10 16 Corner tie bar Exposed Centre Pad QT1081_1R0.04_0307 ...
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... Year of manufacture ‘WW’ = Week of manufacture ‘G’ = Green/RoHS Compliant or ‘XX’ depending upon the IC assembly supplier 'run nr Digit Run Number (depending upon the IC assembly supplier , this line may not appear) Peak Body Temperature O 260 C 17 Specifications IPC/JEDEC J-STD-020C QT1081_1R0.04_0307 ...
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... A minor chip revision (N) is defined as a revision change which does not affect product functionality or datasheet. lQ Part Number QT1081_MXN.nn_mmyy N = Minor chip revision Prereleased Product [ Released Product]) The value only stated for released parts (R). 18 Datasheet Issue Number Datasheet Release Date; (Where mm = Month Year) QT1081_1R0.04_0307 ...
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... NOTES QT1081_1R0.04_0307 ...
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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 ...