Application Notes

AN041 Getting Started with the KX023 and KX022 AN041 Getting Started with the KX023 and KX022

This application note will help developers quickly implement proof-of-concept designs using the KX023 and KX022 tri-axis accelerometer. Please refer to the KX023 and KX022 data sheet for additional implementation guidelines. Kionix strives to ensure that our accelerometers will meet design expectations by default, but it is not possible to provide default settings to work in every environment. Depending on the intended application, it is very likely that some customization will be required in order to optimize performance. The information provided here will help the developer get the most out of the KX023 and KX022.

AN029 Getting Started with the KXCNL Getting Started with the KXCNL

This application note will help developers quickly implement proof-of-concept designs using the KXCNL tri-axis accelerometer. Please refer to the KXCNL data sheet for additional implementation guidelines. The KXCNL provides the capability to define two independent finite state machines with up to 16 states, along with programmable actions initiated at state transitions. This capability allows users to implement a wide range of recognition algorithms such as wake up, free fall, screen orientation, tap/double tap, step recognition, etc.. This application note discusses the implementation of free-fall algorithm utilizing one of the state machines. Required theory, equations, and sample event signature are provided with this note as guidelines for characterizing free-fall models.

AN028 Getting Started with the KXCJ9.pdf AN028 Getting Started with the KXCJ9

This application note will help developers quickly implement proof-of-concept designs using the KXCJ9 tri-axis accelerometer. Please refer to the KXCJ9 data sheet for additional implementation guidelines. While Kionix strives to ensure that our accelerometers will meet design expectations by default, it is not possible to provide default settings to work in every environment. Depending on the intended application, it is very likely that some customization will be required in order to optimize performance. We hope the information provided here will help the developer get the most out of the KXCJ9.

AN038 Getting Started with the KXTJ2 AN038 Getting Started with the KXTJ2

This application note will help developers quickly implement proof-of-concept designs using the KXTJ2 tri-axis accelerometer. Please refer to the KXTJ2 data sheet for additional implementation guidelines. While Kionix strives to ensure that our accelerometers will meet design expectations by default, it has ever so closed the gap by allowing users to autonomously analyze sensor outputs. KXTJ2 is an extension of the KXTJ9 product to a 2 x 2 mm 12-pin. The KXTJ2 is significantly lower in current than our previous offerings. The KXTJ2 provides an I2C bus interface and small 2x2 footprint with 12 pads compatible with Bosch 222/250 series products. The KXTJ2 also provides a low power motion wake up feature which is demonstrated in this application note.

AN039 Getting Started with the KXCJK AN039 Getting Started with the KXCJK

This application note will help developers quickly implement proof-of-concept designs using the KXCJK tri-axis accelerometer. Please refer to the KXCJK data sheet for additional implementation guidelines. While Kionix strives to ensure that our accelerometers will meet design expectations by default, it is not possible to provide default settings to work in every environment. Depending on the intended application, it is very likely that some customization will be required in order to optimize performance. We hope the information provided here will help the developer get the most out of the KXCJK.

AN025 - Getting Started with the KXTI9 Getting Started with the KXTI9

This application note will help developers quickly implement proof-of-concept designs using the KXTI9 tri-axis accelerometer. Please refer to the KXTI9 data sheet for additional implementation guidelines. While Kionix strives to ensure that our accelerometers will meet design expectations by default, it is not possible to provide default settings to work in every environment. Depending on the intended application, it is very likely that some customization will be required in order to optimize performance. We hope the information provided here will help the developer get the most out of the KXTI9.

AN023 Getting Started with the KXTF9 Getting Started with the KXTF9

This application note will help developers quickly implement proof-of-concept designs using the KXTF9 tri-axis accelerometer. Please refer to the KXTF9 data sheet for additional implementation guidelines. While Kionix strives to ensure that our accelerometers will meet design expectations by default, it is not possible to provide default settings to work in every environment. Depending on the intended application, it is very likely that some customization will
be required in order to optimize performance. We hope the information provided here will help the developer get the most out of the KXTF9.

AN022 Getting Started with the KXTE9 Getting Started with the KXTE9

This application note will help developers quickly implement proof-of-concept designs using the KXTE9 tri-axis accelerometer. Please refer to the KXTE9 data sheet for additional implementation guidelines. While Kionix strives to ensure that our accelerometers will meet design expectations by default, it is not possible to provide default settings to work in every environment. Depending on the intended application, it is very likely that some customization will
be required in order to optimize performance. We hope the information provided here will help the developer get the most out of the KXTE9

AN021 Self Test Response Self Test Response

Self Test is a standard feature in Kionix MEMS accelerometers that enables our customers to verify that the part is functional. However the customer must use the proper algorithm to ensure functionality. Applicable theories, plots, and equations are provided with this note as guidelines.

AN020 Orientations and Rotations Orientations and Rotations

The fact that accelerometers are sensitive to the gravitational force on the device allows them to be used to determine the attitude of the sensor with respect to the reference gravitational vector. This attitude determination is very useful in leveling or gimballing gyroscopes and magnetometers for use in compass and navigation instruments; determining tilt for game controller applications; and determining tilt or rotation for screen rotation of handheld devices. The method for calculating orientation or rotation depends on the specific application. In this application note a short introduction is given for some of the most common methods.

AN019 Two Accelerometers for Rotation Using Two Tri-Axis Accelerometers for Rotational Measurements

This application note describes how to use two Kionix MEMS low-g accelerometers to enable rotational measurements. Applicable theory, plots and equations are provided with this note as guidelines.

AN018 Interfacing with Bluetooth Interfacing with Bluetooth

This application note provides an example interface for a Kionix accelerometer with an example Bluetooth DIP Module. First, this application note talks about the hardware and software interface that is made between a C8051 microcontroller and the Kionix KXPB5 accelerometer. Next, the hardware and software interface between the Bluetooth DIP Module and the microcontroller are discussed. Finally, there is also an attachment of all the AT Commands for the end user to be able to update the code in order to execute numerous functions of the Bluetooth DIP Module. Hardware connections, schematics, timing diagrams and example code are provided in this application note as well. The applications of this interface include serial streaming of acceleration data to a PC for data logging

AN017 Aux In of KXPB5 Using the Auxillary Input of the KXPB5

This application note explains how to use the auxiliary input of the KXPB5 accelerometer to add an analog sensor input to any application that uses the KXPB5 in SPI mode (mode 00). This feature is useful for adding an analog input to an application where there are no analog inputs available in the main microprocessor, only a SPI bus. As an example, this application note shows a single-axis gyroscope connected to the auxiliary input of the KXPB5. The KXPB5 receives the analog output of the gyroscope and converts it to a 12-bit digital signal that can be read through SPI communication. A recommended circuit schematic and example SPI communication are included.

AN016 Warranty protection Warranty Protection Using a Kionix MEMS Tri- Axis Accelerometer

This application note describes how to use a Kionix MEMS tri-axis accelerometer as part of a warranty protection system. The system will record free-fall events or high-g events which might void warranty agreements. It can be integrated into a hand-held or portable electronic device or be used as an external module (in a shipping container, for example).

AN015 Integration of Evaluation Boards Integrating the Kionix Tri-Axis Accelerometer Evaluation Board with Microcontroller Development Boards

In this application note, a description of the Kionix evaluation board is given. Then, through schematics and photographs, the hardware connections between some example microcontroller development boards and Kionix evaluation boards are shown. Finally, some example firmware is given to demonstrate communication between the microcontroller and the Kionix accelerometer.

AN013 Position Determination Using Accelerometers Position Determination Using Accelerometers

Quite often the possibility of using accelerometers to track position is investigated. We present in this application note the considerations that must be made for using accelerometers in position determination.

AN012 Accelerometer Errors Accelerometer Errors

This application note explains the sources of error in Kionix MEMS tri-axis accelerometers. Suggestions are made on how to reduce or eliminate the error in the measurements. In this way, applications can be made more accurate and precise.

AN011 Screen Rotation Screen Rotation and Device Orientation

This application note describes how to use a Kionix tri-axis accelerometer to perform a screen rotation function and a device orientation function on a portable handheld electronic device. An accelerometer is used to measure the orientation of the device. Based on the orientation of the device, images and text can be rotated on the screen to appear upright to the user.

AN009 Getting Started with the KXPS5 Getting Started with the KXPS5

This application note will help users quickly implement proof-of-concept designs using the I2C or SPI digital interfaces of the KXPS5 tri-axis accelerometer. Please refer to the KXPS5 Data Sheet for additional implementation guidelines.

AN006 Handheld Electronic Compass Applications Using a Kionix MEMS Tri-axis Accelerometer Handheld Electronic Compass Applications Using a Kionix MEMS Tri-axis Accelerometer

This application note explains the integration of a Kionix MEMS tri-axis accelerometer into a handheld electronic compass application. Required theory, plots, equations and circuit block diagrams are provided with this note as guidelines.

AN005 Tilt Sensing Tilt-Sensing with Kionix MEMS Accelerometers

Tilt/Inclination sensing is a common application for low-g accelerometers. This application note describes how to use Kionix MEMS low-g accelerometers to enable tilt sensing. Applicable theory, plots and equations are provided with this note as guidelines.

AN004 Utilizing the Power Shutdown Capabilities of the Kionix Tri-Axis Accelerometers Utilizing the Power Shutdown Capabilities of the Kionix Tri-Axis Accelerometers

Kionix tri-axis accelerometers feature a power shutdown capability. Even with their typically low current draw, there are still applications that may require even less power consumption. For these applications, it is possible to implement a duty-cycle power-reduction methodology that uses a microprocessor to toggle the Enable/Disable pin or register at a specified duty-cycle. This approach can reduce greatly the accelerometer’s current draw during the majority of its time in operation. This application note provides the theory and equations needed to take full advantage of this power saving capability.

AN003 Multiplexing Tri-Axis Accelerometer Outputs Multiplexing Tri-Axis Accelerometer Outputs

A Kionix tri-axis accelerometer with analog outputs provides three output voltages (Xout, Yout, Zout) which are proportional to the respective accelerations in those directions. However, with three analog outputs to digitize, it is possible that the system microprocessor does not have the necessary A-D converters. One solution is to use the internal multiplexing capability of several Kionix accelerometer products to multiplex the three outputs to one analog signal. Another solution is to use an off  the shelf multiplexer to multiplex the three outputs of the tri-axis accelerometer to one analog signal.

Interfacing the KXP94 or KXR94 Tri-Axis Accelerometer with the Texas Instruments MSP430F149 Microprocessor to Measure Tilt Interfacing the KXP94 or KXR94 Tri-Axis Accelerometer with the Texas Instruments MSP430F149 Microprocessor to Measure Tilt and Other Motions

This application report describes how to integrate the Kionix KXP94 or the KXR94 tri-axis accelerometer with the MSP430F149 to capture and utilize the motion sensing capabilities of the accelerometer. Example code is provided for capturing and using tilt sensing, vibration sensing and acceleration. Source code is provided for the MSP430F149 as well as source code for the demonstration software drivers and applications.

AN001 Drop-Force Modeling Using Kionix Tri-axis Accelerometer Drop-Force Modeling Using Kionix Tri-axis Accelerometer

This application note describes how to use a Kionix MEMS tri-axis accelerometer as a free-fall sensor for drop force modeling applications. Required theory, equations, and sample event signatures are provided with this note as guidelines for characterizing drop force models.