Text version of the page

Contents

1 Overview

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3 4 Operating Modes

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11
1.1 Introduction

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3
4.1 Introduction

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11
1.2 Burst Operation

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3
4.2 Free Run Mode

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11
1.3 User Interface Layout Options

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3
4.3 LP Mode

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11
1.4 Slider and Wheel Construction

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3
4.4 Sleep Mode

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12
1.5 QMagicTM Proximity Effect

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3
4.5 Sync Mode

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12
1.6 SPI Interface

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3 5 Reset

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14
1.7 Basic Power Modes

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4
5.1 Introduction

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14
1.7.1 Overview

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4
5.2 Delay to SPI Functionality

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14
1.7.2 Free Run Mode

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4
5.3 Reset Delay to Touch Detection

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14
1.7.3 LP Mode

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4
5.4 Mode Setting After Reset

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14
1.7.4 Sleep Mode

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4 6 Design Notes

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14
1.7.5 Sync Mode

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4
6.1 Oscillator Frequency

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14 2 Signal Processing

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4
6.2 Spread-spectrum Circuit

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14
2.1 Power-up Self-calibration

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4
6.3 Cs Sample Capacitors - Sensitivity

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14
2.2 Drift Compensation

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4
6.4 Rsns Resistors

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15
2.3 Detection Integrator Filter

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4
6.5 Thermal Stability

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15
2.4 AKSTM Adjacent Key Suppression

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4
6.6 Power Supply

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15
2.5 Autorecalibration (MOD)

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4
6.7 PCB Layout and Construction

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15
2.6 QMagicTM Proximity Sensor

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5 7 Specifications

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16
2.7 Faulty and Unused Keys

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5
7.1 Absolute Maximum Specifications

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16
2.8 Wiring

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6
7.2 Recommended Operating Conditions

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16 3 SPI Interface

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8
7.3 AC Specifications

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16
3.1 Introduction

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8
7.4 DC Specifications

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16
3.2 CHANGE Pin

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8
7.5 Signal Processing

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17
3.3 SPI Parameters

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8
7.6 Idd Curves

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18
3.4 SPI Operation

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8
7.7 Mechanical Dimensions - 32-QFN Package

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20
3.5 SPI Host Commands

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9
7.8 Part Marking

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20
3.5.1 Overview

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9
7.9 Moisture Sensitivity Level (MSL)

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21
3.5.2 Normal Command Mode

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9 8 Datasheet Control

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22
3.5.3 Custom Threshold Command Mode

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10
8.1 Changes

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22
3.6 SPI Responses

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10
8.2 Numbering Convention

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22

2QT1106_8 I R0.07_0907