QT220 Datasheet, PDF (1/12 Pages) Quantum Research Group – 2 KEY QTOUCH SENSOR IC

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z Two independent charge-transfer (‘QT’) touch keys
z Individual outputs per channel - active high
z Projects prox fields through any dielectric
z Sensitivity easily adjusted on a per-channel basis
z 100% autocal for life - no adjustments required
z 3.9V ~ 5.5V single supply operation
z 10s, 60s, infinite auto-recal timeout (strap options)
z Sync pin for line sync to suppress noise
z Spread spectrum operation
z Pin options for auto recalibration timings
z Extremely low cost per key
z 20-SSOP Pb-free package
QT220
2 KEY QTOUCH™ SENSOR IC
SNS1A 1
20 SNS2K/OPT1
SNS1K 2
19 SNS2A
n.c. 3
18 OPT2
SPEED 4
n.c. 5
OUT1 6
17
QT220
16
20-SSOP
15
n.c.
n.c.
OSC
OUT2 7
14 VDD
VSS 8
13 /RES
SYNC/SS 9
12 n.c.
n.c. 10
11 n.c.
APPLICATIONS
Š PC Peripherals
Š Backlighted buttons
Š Appliance controls
Š Security systems
Š Access systems
Š Pointing devices
Š Instrument panels
Š Gaming machines
The QT220 charge-transfer (“QT’”) QTouch IC is a self-contained digital sensor IC capable of detecting near-proximity or touch
on 2 electrodes. It allows electrodes to project independent sense fields through any dielectric like glass, plastic, stone,
ceramic, and wood. It can also turn metal-bearing objects into intrinsic sensors, making them responsive to proximity or touch.
This capability coupled with its continuous self-calibration feature can lead to entirely new product concepts , adding high value
to product designs.
Each of the channels operate s independently of the other, and each can be tuned for a unique sensitivity level by simply
changing its sample capacitor value. Two speeds are supported, one of which consumes on ly 90µA of typical current at 4V.
Unique among capacitance sensors, the device incorporates spread spectrum modulation for unsurpassed EMC compliance.
The devices are designed specifically for human interfaces, like control panels, appliances, gaming devices, lighting controls,
or anywhere a mechanical switch or button may be found; they may also be used for some material sensing and control
applications.
These devices feature a SYNC pin which allows for synchronization with additional similar parts and/or to an external source to
suppress interference. This pin doubles as a drive pin for spread-spectrum modulation. Option pins are provided which allow
different timing and feature settings.
The RISC core of these devices use signal processing techniques pioneered by Quantum which are designed to survive
numerous real-world challenges, such as ‘stuck sensor’ conditions, component ageing, moisture films, and signal drift. By
using the charge transfer principle, these devices deliver a level of performance clearly superior to older technologies yet are
highly cost-effective.
AVAILABLE OPTIONS
TA
-40⁰C to +85⁰C
SSOP-20
QT220-ISSG
LQ
Copyright © 2005 QRG Ltd
QT220R R1.02/0905