QT118HA-ISG Atmel, QT118HA-ISG Datasheet

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... This device is intended as a replacement for the QT118H in existing designs already in production, but is not recommended for new designs. consult your local Atmel or Quantum representative differences. For further device migration plans please QT118HA-ISG R N ECOMMENDED FOR EW Vdd 1 8 Out 2 7 Opt1 3 6 Opt2 ...

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... OVERVIEW The QT118HA is intended to replace the QT118H as a lower cost alternative. This device functions identically to the QT118H, except that it is more sensitive. To compensate for the sensitivity increase required to do either of these two things: 1. Increase the Cx loading to ground on SNS2 by 10pF 2. Decrease the Cs value Option 1 is very simple and guarantees that the sensitivity of the QT118HA is identical to the older device ...

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... AC ground return. 1.3.5 S 1.3.5.1 Gain Pin The QT118HA 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 ...

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... Tie Pin 5 to: while there is no detection in effect. The rate of adjustment Leave open must be performed slowly, otherwise legitimate detections could be ignored. The QT118HA drift compensates using a Pin 6 slew-rate limited change to the reference level; the threshold Pin 7 and hysteresis values are slaved to this reference. ...

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... As the basic burst spacing is 95ms, if this spacing was maintained through 4 consecutive bursts the sensor would be very slow to respond. In the QT118HA, after an initial detection is sensed, the remaining three bursts are spaced only about 2ms apart, so that the slowest reaction time possible is the fastest possible ...

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... Note that the piezo drive does not operate in Pulse mode. 2.2.6 O The QT118HA’s output is active high and it can source or sink 1mA 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 ...

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... CMOS LDO regulators that have nanoamp quiescent currents. Care should be taken that the regulator does not have a minimum load specification, which almost certainly will be violated by the QT118HA's low current requirement. Furthermore, some LDO regulators are unable to provide adequate transient regulation between the quiescent and acquire states, creating Vdd disturbances that will interfere with the acquisition process ...

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... Do not place the electrode or its connecting trace near other traces, or near a ground plane use a ground plane under and around the QT118HA itself, back to the regulator and power connector (but not beyond the Cs capacitor not place an electrode (or its wiring) of one QT device near the electrode or wiring of another device, to prevent cross interference ...

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... Typ Max Units 550 0.5 50 129 3 300 165 O C, unless otherwise noted. Min Typ Max 6, 12 750 +125 Notes ms µ 5.0V Vdd ms @ 3.3V Vdd ms Depends on Cs kHz ms ms µs kHz Units Notes counts samples ms/level 4 ms/level 4 secs 3, 4 QT118HA_AR1.02_0408 O C ...

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... OPT1, OPT2 V OPT1, OPT2 0.6 V OUT, 4mA sink V OUT, 1mA source ±1 µA OPT1, OPT2 14 bits 28 fF Figure 4-2 - Typical Threshold Sensitivity vs. Cx, Medium Gain, Selected Values of Cs; Vdd = 3.0 10.00 1.00 0.10 0. Load 4.5 5 QT118HA_AR1.02_0408 10nF 20nF 50nF 100nF 200nF 500nF 50 ...

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... M 4.800 W 5.816 Aa 3.81 H 1.371 h 0.101 D 1.27 L 0.355 E 0.508 e 0.19 ß 0.381 Ø 0º ORDERING INFORMATION PART QT118HA-ISG Package type: 8 pin SOIC Millimeters Max Notes 4.979 6.198 3.988 1.728 0.762 1.27 BSC 0.483 1.016 0.249 0.762 8º TEMP RANGE PACKAGE SO-8 -40 - 85C ...

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Tel: +44 (0)23 8056 5600 Fax: +44 (0)23 80565600 This device covered under one or more of the following United States and international patents: 5,730,165, 6,288,707, 6,377,009, 6,452,514, 6,457,355, 6,466,036, 6,535,200. Numerous further patents are pending which may apply ...