QT240-ISS Atmel, QT240-ISS Datasheet
QT240-ISS
Specifications of QT240-ISS
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QT240-ISS Summary of contents
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... By using the charge transfer principle, these devices deliver a level of performance clearly superior to older technologies yet are highly cost-effective. -40 -40 LQ Appliance controls Security systems AVAILABLE OPTIONS T SSOP- +85 C QT240-ISS +85 C QT240-ISS ™ OUCH Access systems Instrument panels Pointing devices Gaming machines Lead-Free No Yes Copyright © 2003 QRG Ltd QT240 IC ENSOR QT240 1.07/0804 ...
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... Fast, Spread-Spectrum mode: In this mode the device operates with ~40ms response times but higher current drain (~1.5mA @ 4.0V). This mode also supports spread-spectrum operation via a few QT240-ISS ABLE IN ISTING Pin Name Description 1 SNS2 Sense pin (to Rs2 + Cs2) ...
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... C1 22nF added to overly sensitive channels to ground, to reduce their gains. These should be on the order of a few picofarads QT240 SPECIFICS 2.1 SIGNAL PROCESSING These devices process all signals using 16 bit math, using a number of algorithms pioneered by Quantum. These algorithms are specifically designed to provide for high survivability in the face of adverse environmental changes ...
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... Cx should be below 50pF to prevent errors; this value can be read with a conventional capacitance meter with the QT240 removed. The option setting resistors are mandatory and cannot be deleted. The must be strapped to either Vdd or Vss. ...
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... A sync pulse on SYNC/SS in slow mode acts to break the QT240 out of its sleep state between bursts, and to do infinite another burst. The device will then go back to sleep again and await a new SYNC pulse Sync pulse does not arrive within about 90ms, it will wake again and run normally ...
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... The QT240 will track slow changes in Vdd, but can be seriously affected by rapid voltage steps. If the supply is shared with another electronic system, care should be taken to assure that the supply is free of digital spikes, sags, and surges which can cause adverse effects. The supply is best locally regulated using almost any 3-terminal LDO device from 4.0V to 5V. For proper operation a 0.1µ ...
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... Higher values of Rsns will make crosstalk problems worse; try to keep Rsns to 22K or less if possible. In general try to keep the QT240 close to the electrodes and reduce the adjacency of the sense wiring to ground planes lQ and other signal traces; this will reduce the Cx load, reduce interference effects, and increase signal gain ...
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... Fosc; fast mode only; Circuit of Figure 1-2 bursts Fast mode only Notes Units mA Fast mode µA Slow mode, no Sync V/s Req’d for startup, w/o reset circuit V SYNC, RST V SYNC, RST V OUTn, 4mA sink V OUTn, 1mA source µA OPT1, OPT2, OPT3 bits QT240 1.07/0804 O C ...
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... Negative drift compensation rate Fast negative recalibration timer duration Post-detection recalibration timer duration 5 - PACKAGE OUTLINE Seating level SYMBOL C’ ORDERING INFORMATION PART TEMP RANGE QT240-ISS QT240-ISS-G lQ Value 1,000 250 2 10, 60, infinite 209 mil 20-pin SSOP Dimensions Inches (mils) Min Typ Max 291 ...
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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 sale and supply of services which are available online at ...