at42qt1060 ATMEL Corporation, at42qt1060 Datasheet - Page 5

• Manufacturer Part Number: at42qt1060
• Description: Qtouch? 6-channel Sensor Ic
• Manufacturer: ATMEL Corporation

2. Overview
2.1
2.2
2.3
2.4
2.4.1
9505E–AT42–02/09
Introduction
Keys
Standalone Mode
I/O Lines
Overview
The AT42QT1060 (QT1060) is a digital burst mode charge-transfer (QT
driver designed specifically for mobile phone applications. The device can sense from two to six
keys; up to four keys can be disabled by not installing their respective sense capacitors (Cs). It
also has up to seven configurable input/output lines, with Pulse Width Modulation (PWM) for
LED driving.
This device includes all signal processing functions necessary to provide stable sensing under a
wide variety of changing conditions, and the outputs are fully debounced. Only a few external
parts are required for operation.
The QT1060 modulates its bursts in a spread-spectrum fashion in order to heavily suppress the
effects of external noise, and to suppress RF emissions.
The QT1060 can have a minimum of two keys and a maximum of six keys. These can be
constructed in different shapes and sizes. See
dimensions.
Unused keys should be disabled by removing the corresponding Cs and Rs components and
connecting the SNS pins as shown in the “If Unused” column of
unused keys are always pared from the burst sequence in order to optimize speed. See
Section 7. on page 25
The QT1060 can operate in a standalone mode where an I
required. To enter standalone mode, connect SDA to Vss and SCL to Vdd before powering up
the QT1060.
In standalone mode the default start-up values are used except for the I/O mask (Address 23).
The I/O mask is configured so that all the IOs are outputs (IO mask = 0x7F). This means that
key detection is reported via their respective IOs.
There is an input/output (I/O) port consisting of seven lines that can be individually programmed
as inputs or outputs. They can be either a digital type or PWM. The PWM level can be set to 256
possible values and is common to all lines.
The I/O lines are normally initialized as inputs. However, if an I
used and the SDA and SCL pins are connected to Vss and Vdd respectively, then the I/O lines
are initialized as outputs (see
The outputs can also be linked to either the detection channels or the output register to allow the
outputs to be either user controlled or to indicate detection. These options can be set in the pin
control masks (see
Unused I/O lines should be disabled by connecting as shown in the “If Unused” column of
Table 1-1 on page
2. See
Table 6-1 on page
about setting up the keys.
Section 7. on page 25
Section
2.3).
17).
about setting up the I/O lines.
“Features” on page 1
2
C-compatible interface is not
2
C-compatible interface is not
Table 1-1 on page
AT42QT1060
for the recommended
™
) capacitive sensor
2. The
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