QT240-ISS Atmel, QT240-ISS Datasheet - Page 7

• Manufacturer Part Number: QT240-ISS
• Description: IC SENSOR 4CHAN QTOUCH 20SSOP
• Manufacturer: Atmel
• Series: QTouch™r
• Type: Capacitiver

Specifications of QT240-ISS

• Touch Panel Interface: 4, 2-Wire
• Number Of Inputs/keys: 4 Key
• Resolution (bits): 9 b
• Voltage Reference: Internal
• Voltage - Supply: 3.9 V ~ 5 V
• Current - Supply: 1.5mA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 20-SSOP
• Output Type: *
• Interface: *
• Input Type: *
• For Use With: 427-1113 - BOARD EVAL FOR QT240-IS QTOUCH
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 427-1074

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
7
and other signal traces; this will reduce the Cx load, reduce
interference effects, and increase signal gain.
The one and only valid reason to run ground near SNS
traces is to provide crosstalk isolation between traces, and
then only on an as-needed basis.
QT240 1.07/0804