Freescale Semiconductor
Data Sheet: Technical Data
Document Number: MMA955xL
Rev. 3.1, 5/2015
An Energy Efficient Solution by Freescale
MMA955xL Intelligent
Motion-Sensing Platform
MMA9550L
MMA9551L
MMA9553L
MMA9559L
The MMA955xL device an intelligent sensor, incorporating dedicated
accelerometer MEMS transducers, signal conditioning, data conversion, and a
32-bit programmable microcontroller.
This unique blend transforms Freescale’s MMA955xL into an intelligent, highprecision, motion-sensing platform able to manage multiple sensor inputs. This
device can make system-level decisions required for sophisticated applications
such as gesture recognition, pedometer functionality, tilt compensation and
calibration, and activity monitoring.
Top and bottom view
The MMA955xL device is programmed and configured with the CodeWarrior
Development Studio for Microcontrollers software, version 10.1 or later. This
standard integrated design environment enables customers to quickly
implement custom algorithms and features to exactly match their application
needs.
Using the master I2C port, the MMA955xL device can manage secondary
sensors, such as pressure sensors, magnetometers, or gyroscopes. This
allows sensor initialization, calibration, data compensation, and computation
functions to be off-loaded from the system application processor. The
MMA955xL device also acts as an intelligent sensing hub and a highly
configurable decision engine. Total system power consumption is significantly
reduced because the application processor stays powered down until
absolutely needed.
© 2011, 2013, 2015 Freescale Semiconductor, Inc. All rights reserved.
VDDA
VSSA
RGPIO8/PDB_B
Top view
16 15 14
VDD
1
BKGD-MS
/RGPIO9
RESETB
3
4
13 RGPIO7/AN1/
TPMCH1
12 RGPIO6/AN0
TPMCH0
11 RGPIO5/PDB_A/
INT_O
10 VSS
5
7
8
RGPIO3/SDA1/SSB
9 RGPIO4/INT
6
SDA0/RGPIO1/SDI
SCL0/RGPIO0
SCLK
VSS
2
RGPIO2/SCL1/SDO
Hardware Features
• Three accelerometer operating ranges:
– ±2 g suits most hand gestures (orientation detection and tilt control) and
freefall. For tap detection, ±4 g and ±8 g are supported.
– ±4 g covers most regular human dynamics (walking and jogging)
– ±8 g detects most abrupt activities (gaming)
• Integrated temperature sensor
• One slave SPI or I2C interface operating at up to 2 Mbps, dedicated to
communication with the host processor. Default value of the I2C, 7-bit
address is 0x4C. (This can be customized by firmware.)
• One master I2C interface operating at up to 400 kbps that can be used to
communicate with external sensors
• Eight selectable output data rates (ODR), from 488 Hz to 3.8 Hz (extending
farther from 3906 Hz to 0.24 Hz with MMA9559L Firmware version)
• 10, 12, 14, and 16-bit trimmed ADC data formats available
• 1.8 V supply voltage
• 32-bit CPU with MAC unit
• Extensive set of power-management features and low-power modes
• Integrated 16-bit resolution ADC can be used to convert external analog
signals
• Single-Wire, Background-Debug Mode (BDM) pin interface
• 16-KB flash memory
• 2-KB Random Access Memory
• ROM-based flash controller and slave-port, command-line interpreter
• Two-channel timer with input capture, output capture, or edge-aligned PWM
• Programmable delay block for scheduling events relative to start of frame
• A 16-bit, modulo timer for scheduling periodic events
• Minimal external component requirements
• RoHS compliant (–40ºC to +85ºC), 16-pin, 3 x 3 x 1-mm LGA package
16-pin LGA
3 mm x 3 mm x 1 mm
Case 2094-01
Pin connections
Software Features
This device can be programmed to provide any of the following:
• Orientation detection (portrait/landscape)
• High-g/Low-g threshold detection
• Pulse detection (single, double and directional tap)
• Tilt detection
• Auto wake/sleep
• Embedded, smart FIFO
• Power management
• Pedometer
A selection of the software features are included in the factory-programmed firmware for some devices. Users may add their own
features with user firmware.The power and flexibility of the embedded ColdFire V1 MCU core associated with the high performance 3-axis accelerometer give new and unprecedented capabilities to the MMA955xL devices family.
Table 1. Ordering information
Part number
Firmware
Temperature range
Package description
Shipping
MMA9550LR1
Motion
–40°C to +85°C
LGA-16
Tape and reel
MMA9551LR1
Gesture
–40°C to +85°C
LGA-16
Tape and reel
MMA9553LR1
Pedometer
–40°C to +85°C
LGA-16
Tape and reel
MMA9559LR1
Foundation
–40°C to +85°C
LGA-16
Tape and reel
MMA955xL
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Contents
1
2
3
4
5
6
Variations of MMA955xL Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Typical Applications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.1. . Functional Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.2. . Packaging Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.2.1 Package diagrams. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.2.2 Sensing Direction and Output Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.2.3 Pin Functions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.3. . Pin Function Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.4. . System Connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.4.1 Power Sequencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.4.2 Layout Recommendations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.4.3 MMA955xL Platform as an Intelligent Slave . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.4.4 MMA955xL Platform as a Sensor Hub . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Mechanical and Electrical Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.1. . Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.2. . Pin Groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.3. . Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.4. . Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.5. . Electrostatic Discharge (ESD) and Latch-up Protection Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.6. . General DC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.7. . Supply Current Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.8. . Accelerometer Transducer Mechanical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.9. . ADC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.10. ADC Sample Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.11. AC Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.12. General Timing Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.13. I2C Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.13.1 Slave I2C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.13.2 Master I2C Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.14. Slave SPI Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.15. Flash Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
5.1. . Footprint and pattern information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
5.2. . Marking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
5.3. . Tape and reel information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Related Documentation
The MMA955xL device features and operations are described in a variety of reference manuals, user guides, and application
notes. To find the most-current versions of these documents:
1. Go to the Freescale homepage at freescale.com.
2. In the Keyword search box at the top of the page, enter the device number MMA955xL.
3. In the Refine Your Result pane on the left, click on the Documentation link.
MMA955xL
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Variations of MMA955xL Device
Freescale offers a variety of firmware versions for the MMA955xL devices. The different versions of the device are identified by
the fourth digit in the part number (for example MMA9559L). Information and specifications provided in this data sheet are independent of the Freescale firmware versions.
The following table lists some of the variations among the MMA955xL-platform devices.
Table 2. Features of product-line devices
Feature - Device
MMA9550L
MMA9551L
MMA9553L
MMA9559L
Motion sensing
Gesture sensing
Pedometer
High flexibility
User flash available
6.5 KB
4.5 KB
1.0 KB
14 KB
User RAM available
576 bytes
452 bytes
420 bytes
1664 bytes
ADC resolution (bits)
10,12,14,16 bits
10,12,14,16 bits
10,12,14,16 bits
10,12,14,16 bits
2 g, 4 g, 8 g
2 g, 4 g, 8 g
2 g, 4 g, 8 g
2 g, 4 g, 8 g
Real-time and preemptive scheduling
Yes
Yes
Yes
No
Event management
No
No
No
Yes
• Normal mode
Yes
Yes
Yes
No
• Legacy mode
Yes
Yes
Yes
No
• Streaming mode
Yes
Yes
Yes
No
• 100-Hz BW anti-aliasing
Yes
Yes
Yes
No
• 50-Hz BW anti-aliasing
Yes
Yes
Yes
No
• g-mode-dependent resolution
Yes
Yes
Yes
Yes
• Absolute value
Yes
Yes
Yes
No
• Low-pass filter
Yes
Yes
Yes
No
• High-pass filter
Yes
Yes
Yes
No
• Data-ready interrupt
Yes
Yes
Yes
Yes
• High g/Low g
No
Yes
No
No
• Tilt
No
Yes
No
No
• Portrait/Landscape
No
Yes
No
No
• Programmable orientation
No
Yes
No
No
• Tap/Double-tap
No
Yes
No
No
• Freefall
No
Yes
No
No
• Motion
No
Yes
No
No
Key elements
g measurement ranges
Slave Port Command Interpreter
Front-end processing
Gesture applications
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Table 2. Features of product-line devices (Continued)
Feature - Device
MMA9550L
MMA9551L
MMA9553L
MMA9559L
• Data FIFO
Yes
Yes
Yes
No
• Event queue
Yes
Yes
Yes
No
• Inter-process FIFO
No
No
No
Yes
• Run and Stop on idle
Yes
Yes
Yes
Yes
• Run and No stop
Yes
Yes
Yes
Yes
• Stop NC
Yes
Yes
Yes
Yes
• Auto-Wake / Auto-Sleep / Doze
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
• Step count
No
No
Yes
No
• Distance
No
No
Yes
No
• Adaptive distance
No
No
Yes
No
• Activity monitor
No
No
Yes
No
Data-storage modules
Power-control module
Data-management daemons
Pedometer applications
The only difference between the various device configurations is the firmware content that is loaded into the flash memory at the
factory. The user still can add custom software using the remaining portion of flash memory.
MMA9555L is described on a separate data sheet due to the device’s configuration.
The MMA9550L, MMA9551L, and MMA9553L devices can function immediately as they are. They have an internal command
interpreter and applications scheduler and can interact directly with the users’ host system.
The MMA9559L device provides the most flexibility and is for users who need to design their own control loop and system. The
device needs to be programmed with custom user code.
MMA955xL
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2
Typical Applications
This low-power, intelligent sensor platform is optimized for use in portable and mobile consumer products such as:
• Tablets/PMPs/PDAs/digital cameras
– Orientation detection (portrait/landscape)
– Image stability
– Tilt-control enabled with higher resolution
– Gesture recognition
– Tap to control
– Auto wake/sleep for low power consumption
• Smartbooks/ereaders/netbooks/laptops
– Anti-theft
– Freefall detection for hard-disk drives
– Orientation detection
– Tap detection
• Pedometers
• Gaming and toys
• Activity monitoring in medical applications
• Security
– Anti-theft
– Shock detection
– Tilt
• Fleet monitoring, tracking
– System auto-wake on movement
– Detection
– Shock recording
– Anti-theft
• Power tools and small appliances
– Tilt
– Safety shut-off
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General Description
3.1
Functional Overview
The MMA955xL device consists of a 3-axis, MEMS accelerometer and a mixed-signal ASIC with an integrated, 32-bit CPU. The
mixed-signal ASIC can be utilized to measure and condition the outputs of the MEMS accelerometer, internal temperature sensor,
or a differential analog signal from an external device.
The calibrated, measured sensor outputs can be read via the slave I2C or SPI port or utilized internally within the MMA955xL
platform.
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Figure 1. Platform block diagram
A block level view is shown in the preceding figure and can be summarized at a high level as an analog/mixed-mode subsystem
associated with a digital engine:
• The analog subsystem is composed of:
– A 3-axis transducer that is an entirely passive block including the MEMS structures.
– An Analog Front End (AFE) with the following:
• A capacitance-to-voltage converter (CVC)
• An analog-to-digital converter
• A temperature sensor
• The digital subsystem is composed of:
– A 32-bit, CPU with a Background-Debug Module (BDM)
– Memory: RAM, ROM, and flash
– Rapid GPIO (RGPIO) port-control logic
– Timer functions include:
• Modulo timer module (MTIM16)
• Programmable Delay Timer (PDB)
MMA955xL
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–
–
–
–
• General-Purpose Timer/PWM Module (TPM)
I2C master interface
I2C or SPI slave interface
System Integration Module (SIM)
Clock-Generation Module
The slave interfaces (either SPI or I2C) operate independently of the CPU subsystem. They can be accessed at any time, including while the device is in low-power, deep-sleep mode.
3.2
Packaging Information
All pins on the device are utilized and many are multiplexed.
The following sections describe the pinout. Users can select from multiple pin functions via the SIM pin mux-control registers.
VDDA
RGPIO8/PDB_B
Package diagrams
VSSA
3.2.1
Z
16 15 14
VDD
1
13 RGPIO7/AN1/TPMCH1
BKGD-MS/RGPIO9 2
12 RGPIO6/AN0/TPMCH0
RESETB
3
11 RGPIO5/PDB_A/INT_O
SCL0/RGPIO0/SCLK
4
10 VSS
VSS
5
6
7
8
SDA0/RGPIO1/SDI
RGPIO2/SCL1/SDO
RGPIO3/SDA1/SSB
9 RGPIO4/INT
1
X
Y
(TOP VIEW)
Direction of the
detectable accelerations
Figure 2. Device pinout (top view) and package frame convention
MMA955xL
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3.2.2
Sensing Direction and Output Response
The following figure shows the device’s default sensing direction when measuring gravity in a static manner. Also included are
the standard abbreviations or names for the six different orientation modes: portrait up/down, landscape left/right and back/front.
Top View
PU
Pin 1
Gravity
Side View
LL
LR
Xout @ 0 g
Yout @ -1 g
Zout @ 0 g
BACK
Xout @ 0 g
Yout @ 0 g
Zout @ -1 g
PD
Xout @ -1 g
Yout @ 0 g
Zout @ 0 g
Xout @ 1 g
Yout @ 0 g
Zout @ 0 g
FRONT
Xout @ 0 g
Yout @ 0 g
Zout @ 1 g
Xout @ 0 g
Yout @ 1 g
Zout @ 0 g
Figure 3. Sensing direction and output response
3.2.3
Pin Functions
The following table summarizes functional options for each pin on this device.
Table 3. Pin functions
Pin #
Pin Function #1(1)
2
BKGD/MS
RESETB
SCL0
Description
Digital power supply
Background-debug / Mode select / RGPIO9
(2)
RGPIO0
Active-low reset
SCLK
Serial clock for slave I2C / RGPIO0 / Serial clock for slave SPI
Digital ground
VSS
5
6
SDA0
RGPIO1
SDI
Serial data for slave I2C / RGPIO1 / SPI serial data input
7
RGPIO2
SCL1
SDO
RGPIO2 / Serial clock for master I2C / SPI serial data output
8(3)
RGPIO3
SDA1
SSB
RGPIO3 / Serial data for master I2C / SPI slave select
9
RGPIO4
10
INT
RGPIO4 / Interrupt input
RESERVED (Connect to VSS)
Must be grounded externally
RGPIO5 / PDB_A / INT_O slave-port interrupt output.INT_O can
only output interrupts from the COCO bit. Other than for the
MMA9559, use RGPIO6–RGPIO9 for setting sensor data
output interrupts.
11
RGPIO5
PDB_A
INT_O
12
RGPIO6
AN0
TPMCH0
RGPIO6 / ADC Input 0 / TPM Channel 0
13
RGPIO7
AN1
TPMCH1
RGPIO7 / ADC Input 1 / TPM Channel 1
14
15
RGPIO8
16
1.
2.
Pin Function #3
RGPIO9
3
4
Pin Function #2
VDD
1
VDDA
Analog power
PDB_B
RGPIO8 / PDB_B
VSSA
Analog ground
Pin function #1 represents the reset state of the hardware. Pin functions can be changed via the SIM pin, mux-control registers in Freescale or user firmware.
RESETB is an open-drain, bidirectional pin. Reset must be pulled high at startup. After startup, Reset may be asserted to reset the device.
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3.
RGPIO3/SDA1/SSB = Low at startup selects SPI. High at startup selects I2C. This is a function of the application boot code, not of the hardware.
3.3
Pin Function Descriptions
This section provides a brief description of the various pin functions available on the MMA955xL platform. Ten of the device pins
are multiplexed with Rapid GPIO (RGPIO) functions. The “Pin Function #1” column in Table 3 on page 9 lists which function is
active when the hardware exits the Reset state. Freescale or user firmware can use the pin mux-control registers in the System
Integration Module (SIM) to change pin assignments for each pin after reset. For detailed information about these registers, see
the MMA955xL Three-Axis Accelerometer Reference Manual (MMA955xLRM).
VDD and VSS: Digital power and ground. VDD is nominally 1.8 V.
VDDA and VSSA: Analog power and ground. VDDA is nominally 1.8 V. To optimize performance, the VDDA line can be filtered to
remove any digital noise that can be present on the 1.8 V supply. (See Figure 5 and Figure 6 on page 16.)
RESETB: The RESETB pin is an open-drain, bidirectional pin with an internal, weak, pullup resistor. At start-up, it is configured
as an input pin, but also can be programmed to become bidirectional. Using this feature, the MMA955xL device can reset external
devices for any purpose other than power-on reset. Reset must be pulled high at power up to boot to Application code space. If
low, it will boot to ROM code. After startup, Reset may be asserted to reset the device. The total external capacitance to ground
has to be limited when using RESETB-pin, output-drive capability. For more details, see the “System Integration Module” chapter
of the MMA955xL Three-Axis Accelerometer Reference Manual (MMA955xLRM).
Slave I2C port: SDA0 and SCL0: These are the slave-I2C data and clock signals, respectively. The MMA955xL device can be
controlled via the serial port or via the slave SPI interface.
Master I2C: SDA1 and SCL1: These are the master-I2C data and clock signals, respectively.
Analog-to-Digital Conversion: AN0, AN1: The on-chip ADC can be used to perform a differential, analog-to-digital conversion
based on the voltage present across pins AN0(-) and AN1(+). Conversions for these pins are at the same Output Data Rate
(ODR) as the MEMS transducer signals. Input levels are limited to 1.8 V differential.
Rapid General Purpose I/O: RGPIO[9:0]: The CPU has a feature called Rapid GPIO (RGPIO). This is a 16-bit, input/output port
with single-cycle write, set, clear, and toggle functions available to the CPU. The MMA955xL device brings out the lower 10 bits
of that port as pins of the device. At reset, All of the RGPIO pins are configured as input pins, although pin muxing does reassign
some pins to non-RGPIO function blocks. Pull-ups are disabled.
RGPIO[9] is connected to BKGD/MS. RGPIO[9:6] can be set as interrupt pins for most interrupt sources.
RGPIO[1:0] SDA0 and SCL0 are connected at reset.
Interrupts: INT: This input pin can be used to wake the CPU from a deep-sleep mode. It can be programmed to trigger on either
rising or falling edge, or high or low level. This pin operates as a Level-7 (high-priority) interrupt.
Debug/Mode Control: BKGD/MS: At start-up, this pin operates as mode select. If this pin is pulled high during start up, the CPU
will boot normally and run code. If this pin is pulled low during start-up, the CPU will boot into active Background-Debug Mode
(BDM). In BDM, this pin operates as a bidirectional, single-wire, background-debug port. It can be used by development tools for
downloading code into on-chip RAM and flash and to debug that code. There is an internal pullup resistor on this pin. It may be
left floating.
Timer: PDB_A and PDB_B: These are the two outputs of the programmable delay block.
Slave SPI Interface: SCLK, SDI, SDO and SSB: These pins control the slave SPI clock, data in, data out, and slave-select
signals, respectively. The MMA955xL platform can be controlled via this serial port or via the slave-I2C interface. SSB has a special function at startup that selects the Slave interface mode. Low at startup selects SPI and high selects I2C.
INT_O: The slave-port output interrupt pin. This pin can be used to flag the host when a response to a command is available to
read on the slave port. This Interrupt pin can only output the COCO bit interrupt. Other than for the MMA9559, use RGPIO6–
RGPIO9 for full interrupt capability.
TPMCH0 and TPMCH1: The I/O pin associated with 16-bit, TPM channel 0 and 1.
3.4
System Connections
3.4.1
Power Sequencing
An internal circuit powered by VDDA provides the device with a power-on-reset signal. In order for this signal to be properly recognized, it is important that VDD is powered up before or simultaneously with VDDA. The voltage potential between VDD and VDDA
must not be allowed to exceed the value specified in Table 7 on page 16.
MMA955xL
10
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Freescale Semiconductor, Inc.
3.4.2
•
•
•
•
•
•
•
•
•
•
Layout Recommendations
Provide a low-impedance path from the board power supply to each power pin (VDD and VDDA) on the device and from the
board ground to each ground pin (VSS and VSSA).
Place 0.01 to 0.1 µF capacitors as close as possible to the package supply pins to meet the minimum bypass requirement.
The recommended bypass configuration is to place one bypass capacitor on each of the VDD/VSS pairs. VDDA/VSSA ceramic
and tantalum capacitors tend to provide better tolerances.
Ensure that capacitor leads and associated printed-circuit traces that connect to the chip VDD and VSS (GND) pins are as
short as possible.
Bypass the power and ground with a capacitor of approximately 1 µF and a number of 0.1-µF ceramic capacitors.
Minimize PCB trace lengths for high-frequency signals. This is especially critical in systems with higher capacitive loads that
could create higher transient currents in the VDD and VSS circuits.
Take special care to minimize noise levels on the VDDA and VSSA pins.
Use separate power planes for VDD and VDDA and separate ground planes for VSS and VSSA. Connect the separate analog
and digital power and ground planes as close as possible to power supply outputs. If both analog circuit and digital circuits
are powered by the same power supply, it is advisable to connect a small inductor or ferrite bead in series with both the VDDA
and VSSA traces.
Physically separate the analog components from noisy digital components by ground planes. Do not place an analog trace
in parallel with digital traces. It is also desirable to place an analog ground trace around an analog signal trace to isolate it
from digital traces.
Provide an interface to the BKGD/MS pin if in-circuit debug capability is desired.
Ensure that resistors RP1 and RP2, in the following figure, match the requirements stated in the I2C standard. For the shown
configuration, the value of 4.7 kΩ would be appropriate.
3.4.3
MMA955xL Platform as an Intelligent Slave
I2C pullup resistors, a ferrite bead, and a few bypass capacitors are all that are required to attach this device to a host platform.
The basic configurations are shown in the following two figures. In addition, the RGPIO pins can be programmed to generate
interrupts to a host platform in response to the occurrence of real-time application events. In this case, the pins should be routed
to the external interrupt pins of the CPU.
NOTE
Immediately after a device reset, the state of pin number 8 (RGPIO3/SDA1/SSB functions) is used to select the slave port interface mode. This implies important rules in the way the host controller or, more generally, the complete system should be handling
this pin.
First of all, whenever a reset occurs on the MMA955xL, the RGPIO3 pin level shall be consistent with the interface mode of operation. This is particularly important if this pin is driven from external devices. If the RGPIO3 level does not match the current
mode of operation, an alternate mode is selected and communication with the host is lost.
If I2C mode is used, a good practice is to tie RGPIO3 to a pull-up resistor so that it defaults to high level. Note that such a connection exists when the Master I2C interface is used (SDA1 function for pin 8). When using I2C mode for the slave interface, the
RGPIO3 pin plays two roles: RGPIO3 and mode selection. When the MMA955xL is powered on and the mode selection is I2C,
the RGPIO3 pin is released as a GPIO pin. The default setting of RGPIO3 is as an output pin and output low. In order to reduce
the leakage current on the pull-up resistor, a large resistor value can be used or RGPIO3 can be set as an input pin.
When using SPI mode for the slave interface, the situation is more complex as the same pin plays two roles: SSB and mode
selection. Moreover, after a SPI read or write operation, the SSB line returns to high level. Consequently, if the host is sending a
command to the MMA955xL that induces a subsequent reset, immediately after the write transaction, the host shall force the
SSB line to low level so that SPI mode is still selected after reset. Keeping the duration for the SSB line low typically depends on
the latency between the write transaction and the execution of the reset command. Such latency can be significant for the
MMA9553L pedometer firmware as the Command Interpreter and Scheduler Application are running at 30 Hz, which gives a 33
ms typical latency. The MMA9550L and MMA9551L firmware, on the other hand, operate the Command Interpreter and Scheduler Applications at 488 Hz, which gives a 2 ms typical latency.
The rule obviously applies also when a hardware reset is issued by the host through MMA955xL pin number 3 (RESETB active
low). Again the host has to drive the SSB line low prior to release of the hardware reset line to high level, which triggers immediate
MMA955xL reset and boot sequence. Keeping the SSB line low for a 1 ms duration (after RESETB is released) is enough for the
MMA955xL slave device to reboot into SPI mode.
MMA955xL
Sensors
Freescale Semiconductor, Inc.
11
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MMA955xL
Sensors
Freescale Semiconductor, Inc.
13
3.4.4
MMA955xL Platform as a Sensor Hub
The MMA955xL device includes:
• a powerful 32-bit CPU
• a second I2C bus
• one external analog input
These features can all be monitored using the on-chip ADC.
The combination of low power consumption and powerful features means that the MMA955xL platform can effectively operate
as a power controller for handheld units such as industrial scanners, PDAs, and games. The host platform can put itself to sleep
with confidence that the MMA955xL device will issue a wake request should any external event require its attention.
The following figure illustrates the MMA955xL device being used in this configuration. Observe how all that is required is a few
bypass capacitors, a ferrite bead, and some pullup resistors for the I2C buses.
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MMA955xL
14
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Freescale Semiconductor, Inc.
4
Mechanical and Electrical Specifications
This section contains electrical specification tables and reference timing diagrams for the MMA955xL device, including detailed
information on power considerations, DC/AC electrical characteristics, and AC timing specifications.
4.1
Definitions
Cross-axis sensitivity
The proportionality constant that relates a variation of accelerometer output to cross acceleration. This
sensitivity varies with the direction of cross acceleration and is primarily due to misalignment.
Full range
The algebraic difference between the upper and lower values of the input range. Refer to the input/
output characteristics.
Hardware compensated Sensor modules on this device include hardware-correction factors for gain and offset errors that are
calibrated during factory test using a least-squares fit of the raw sensor data.
Linearity error
The deviation of the sensor output from a least-squares linear fit of the input/output data.
Nonlinearity
The systematic deviation from the straight line that defines the nominal input/output relationship.
Pin group
the clustering of device pins into a number of logical pin groupings to simplify and standardize electrical
data sheet parameters. Pin groups are defined in Section 4.2, “Pin Groups”.
Software compensated
Freescale’s advanced non-linear calibration functions that—with the first-order hardware gain and offset calibration features—improve sensor performance.
Warm-up time
The time from the initial application of power for a sensor to reach its specified performance under the
documented operating conditions.
4.2
Pin Groups
The following pin groups are used throughout the remainder of this section.
Group 1
RESETB
Group 2
RESERVED
Group 3
RGPIO[9:0]
4.3
Absolute Maximum Ratings
Absolute maximum ratings are the limits the device can be exposed to without permanently damaging it. Absolute maximum ratings are stress ratings only; functional operation at these ratings is not guaranteed. Exposure to absolute maximum ratings conditions for extended periods may affect reliability.
This device contains circuitry to protect against damage due to high static voltage or electrical fields. It is advised, however, that
normal precautions be taken to avoid application of any voltages higher than maximum-rated voltages to this high-impedance
circuit. Reliability of operation is enhanced if unused inputs are tied to an appropriate logic voltage level (for instance, either VSS
or VDD).
Table 4. Absolute maximum ratings
Rating
Symbol
Minimum
Maximum
Unit
Digital supply voltage
VDD
-0.3
2.0
V
Analog supply voltage
VDDA
-0.3
2.0
V
Voltage difference, VDD to VDDA
VDD - VDDA
-0.1
0.1
V
Voltage difference, VSS to VSSA
VSS - VSSA
-0.1
0.1
V
VIn
-0.3
VDD + 0.3
V
Input voltage
IC
-20
20
mA
VOUTOD
-0.3
VDD + 0.3
V
Storage temperature
Tstg
-40
125
°C
Mechanical shock
SH
5k
g
Input/Output pin-clamp current
Output voltage range (Open-Drain Mode)
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4.4
Operating Conditions
Table 5. Nominal operating conditions
Rating
4.5
Symbol
Min
Typ
Max
Unit
Digital supply voltage
VDD
1.71
1.8
1.89
V
Analog supply voltage
VDDA
1.71
1.8
1.89
V
Voltage difference, VDD to VDDA
VDD - VDDA
-0.1
—
0.1
V
Voltage difference, VSS to VSSA
VSS - VSSA
-0.1
—
0.1
V
Input voltage high
VIH
0.7*VDD
—
VDD+0.1
V
Input voltage low
VIL
VSS - 0.3
—
0.3*VDD
V
Operating temperature
TA
-40
25
85
°C
Electrostatic Discharge (ESD) and Latch-up Protection Characteristics
Table 6. ESD and latch-up protection characteristics
Rating
Symbol
Min
Max
Unit
Human Body Model (HBM)
VHBM
±2000
—
V
Machine Model (MM)
VMM
±200
—
V
Charge Device Model (CDM)
VCDM
±500
—
V
ILAT
±100
—
mA
Latch-up current at 85°C
4.6
General DC Characteristics
Table 7. DC characteristics(1)
Symbol
Condition(s)(2)
Min
Typ
Max
Unit
Output voltage high
• Low-drive strength
• High-drive strength
VOH
Pin Groups 1 and 3
ILOAD = –2 mA
ILOAD = –3 mA
VDD – 0.5
—
—
V
Output voltage low
• Low-drive strength
• High-drive strength
VOL
Pin Groups 1 and 3
ILOAD = 2 mA
ILOAD = 3 mA
—
—
0.5
V
Output-low current
Max total IOL for all ports
IOLT
—
—
24
mA
Output-high current
Max total IOH for all ports
IOHT
—
—
24
mA
Input-leakage current
|IIN|
Pin Group 2
Vin = VDD or VSS
—
0.1
1
µA
Hi-Z (off-state) leakage current
|IOZ|
Pin Group 3 input
resistors disabled
Vin = VDD or VSS
—
0.1
1
µA
Pullup resistor
RPU
when enabled
17.5
52.5
KΩ
Power-on-reset voltage
VPOR
—
—
1.50
—
V
VPOR-hys
—
—
100
—
mV
CIN
—
—
7
—
pF
COUT
—
—
7
—
pF
Characteristic
Power-on-reset hysteresis
Input-pin capacitance
Output-pin capacitance
1.All conditions at nominal supply: VDD = VDDA = 1.8 V.
2.Pin groups are defined in “Pin Groups” on page 15.
MMA955xL
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4.7
Supply Current Characteristics
Table 8. Supply current characteristics(1)
Characteristic
Supply current in STOPNC mode
Supply current in STOPSC mode
Supply current in RUN mode(2)
1.
2.
Symbol
Condition(s)
Min
Typ
Max
Unit
IDD-SNC
Internal clocks disabled
—
2
—
µA
IDD-SSC
Internal clock in
slow-speed mode
—
15
—
µA
IDD-R
Internal clock in
fast mode
—
3.1
—
mA
All conditions at nominal supply: VDD = VDDA = 1.8V.
Total current with the analog section active, 16 bits ADC resolution selected, MAC unit used and all peripheral clocks enabled.
4.8
Accelerometer Transducer Mechanical Characteristics
Table 9. Accelerometer characteristics
Characteristic
Symbol
AFR
Full range
ASENS
Sensitivity/resolution
Condition(s)
Min
Typ
Max
2g
±1.8
±2
±2.2
4g
±3.6
±4
±4.4
8g
±7.2
±8
±8.8
2g
—
0.061
—
4g
—
0.122
—
8g
—
0.244
—
Unit
g
mg/LSB
2g
Zero-g level offset accuracy
(Pre-board mount)
OFFPBM
–100
+100
mg
8g
Nonlinearity
Best-fit straight line
ANL
TCSA
Sensitivity change vs.temperature
Zero-g level change vs. temperature
4g
(1)
TCOff
2g
—
±0.25
4g
—
±0.5
—
—
8g
—
±1
—
2g
—
±0.17
—
%/°C
—
—
±1.9
—
mg/°C
+100
mg
% AFR
2g
Zero-g Level offset accuracy
(Post-board mount)
OFFBM
BW
Noise
—
Cross-axis sensitivity
1.
4.9
–100
8g
Output data bandwidth
Output noise
4g
—
—
ODR/2
—
Hz
2 g, ODR = 488 Hz
—
100
—
µg/sqrt(Hz)
8 gg, ODR = 488 Hz
—
120
—
µg/sqrt(Hz)
—
–5
—
5
%
Relative to 25°C.
ADC Characteristics
Table 10. ADC characteristics(1)
Characteristic
Symbol
Condition(s)
Min
Typ
Max
Unit
Input voltage
VAI
Voltage at AN0 or AN1
0.2
—
1.1
V
Differential input voltage
VADI
AN1 - AN0
-0.9
—
0.9
V
Full-scale range
VFS
—
—
1.8
—
V
Programmable resolution
RES
—
10
14
16
Bits
tc
—
—
207
—
µs
INL
Full Scale
—
±15
—
LSB
Conversion time @ 14-bits resolution
(Three-sample frame)
Integral nonlinearity
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Table 10. ADC characteristics(1)
Characteristic
Symbol
Condition(s)
Min
Typ
Max
Unit
DNL
—
—
±2
—
LSB
IIA
—
—
—
±2
µA
Differential nonlinearity
Input leakage
1.
All conditions at nominal supply: VDD = VDDA = 1.8 V and RES = 14, unless otherwise noted.
4.10
ADC Sample Rates
The MMA955xL platform supports the following sample rates:
•
488.28 frames per second (fps)
•
244.14 fps
•
122.07 fps
•
61.04 fps
•
30.52 fps
•
15.26 fps
•
7.63 fps
•
3.81 fps
In addition to the previous list, additional sample rates are available with the MMA9559L device.
•
3906.25 fps (for 10- and 12-bit mode only)
•
1953.13 fps
•
976.56 fps
•
1.91 fps
•
0.95 fps
•
0.48 fps
•
0.24 fps
Note: The highest rate has a restriction in terms of ADC resolution selection as time available for data conversion is much
reduced.
MMA955xL
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4.11
AC Electrical Characteristics
Tests are conducted using the input levels specified in Table 5 on page 16. Unless otherwise specified, propagation delays are
measured from the 50-percent to 50-percent point. Rise and fall times are measured between the 10-percent and 90-percent
points, as shown in the following figure.
Low
VIH
Input Signal
High
90%
50%
10%
Midpoint1
VIL
Fall Time
Rise Time
Note: The midpoint is VIL + (VIH – VIL)/2.
Figure 7. Input signal measurement references
The subsequent figure shows the definitions of the following signal states:
• Active state, when a bus or signal is driven and enters a low-impedance state
• Three-stated, when a bus or signal is placed in a high-impedance state
• Data Valid state, when a signal level has reached VOL or VOH
• Data Invalid state, when a signal level is in transition between VOL and VOH
Data1 Valid
Data1 Valid
Data3 Valid
Data2
Data1
Data3
Data
3-stated
Data Invalid State
Data Active
Data Active
Figure 8. Signal states
4.12
General Timing Control
Table 11. General timing characteristics(1)
Characteristic
Symbol
Condition(s)
Min
Typ
—
Max
Unit
VDD rise time
Trvdd
10% to 90%
—
POR release delay(2)
TPOR
Power-up
0.35
Warm-up time
TWU
From STOPNC
—
7
—
FOPH
FOPL
tCYCH
tCYCL
Full Speed Clock
Slow Clock
Full Speed Clock
Slow Clock
—
—
—
—
8
62.5
125
16
—
—
—
—
Full/Slow clock ratio
—
—
—
128
—
Oscillator frequency absolute accuracy @ 25°C
—
Full Speed Clock
-5
—
+5
%
Oscillator frequency variation over temperature
(-40°C to 85°C vs. ambient)
—
Slow Clock
-6
—
+6
%
Minimum RESET assertion duration
tRA
—
4T(3)
—
—
—
Frequency of operation
System clock period
1.
2.
3.
1
ms
1.5
ms
sample
periods
MHz
KHz
ns
μs
All conditions at nominal supply: VDD = VDDA = 1.8 V
This is the time measured from VDD = VPOR until the internal reset signal is released.
In the formulas, T = 1 system clock cycle. In full speed mode, T is nominally 125 ns. In slow speed mode, T is nominally 16 μs.
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I2C Timing
4.13
This device includes a slave I2C module that can be used to control the sensor and can be active 100 percent of the time. It also
includes a master/slave I2C module that should be used only during CPU run mode (ΦD).
SDA
tf
tf
tSU; DAT
tr
tLOW
tHD; STA
tr
tSP
tBUF
SCL
tSU; STA
tHD; STA
S
tHD; DAT
tSU; STO
SR
tHIGH
P
S
Figure 9. I2C standard and fast-mode timing
4.13.1
Slave
I2C
Table 12. I2C Speed Ranges
Max Baud
Rate (fSCL)
Min
Bit Time
Min SCL Low
(tLOW)
Min SCL High
(tHIGH)
Min Data setup Time
(tSU; DAT)
Min/Max Data Hold Time
(tHD; DAT)
Standard
100 KHz
10 μs
4.7 μs
4 μs
250 ns
0 μs/3.45 μs(1)
Fast
400 KHz
2.5 μs
1.3 μs
0.6 μs
100 ns
0 μs/0.9 μs(1)
1 MHz
1 μs
500 ns
260 ns
50 ns
0 μs/0.45 μs(1)
2.0 MHz
0.5 μs
200 ns
200 ns
10 ns(2)
0 ns/70 ns (100 pf)(2)
Mode
Fast +
High-speed
supported
1.
2.
The maximum tHD; DAT must be at least a transmission time less than tVD;DAT or tVD;ACK. For details, see the I2C standard.
Timing met with IFE = 0, DS = 1, and SE = 1. See the “Port Controls” chapter in the MMA955xL Three-Axis Accelerometer Reference Manual
(MMA955xLRM).
4.13.2
Master I2C Timing
The master I2C module should only be used when the system clock is running at full rate. The master I2C should not be used
across frames when a portion of time is spent in low speed mode.
Table 13. Master I2C timing
Characteristic
Symbol
Standard Mode
Fast Mode
Unit
Min
Max
Min
Max
fSCL
0
100
0
400
kHz
tHD; STA
4.0
—
0.6
—
μs
LOW period of the SCL clock
tLOW
4.7
—
1.3
—
μs
HIGH period of the SCL clock
tHIGH
4.0
—
0.6
—
μs
SCL clock frequency
Hold time (repeated) START condition. After this period, the first
clock pulse is generated.
Setup time for a repeated START condition
tSU; STA
4.7
—
0.6
—
μs
Data hold time for I2C-bus devices
tHD; DAT
0(1)
3.45(2)
0(1)
0.9(2)
μs
Data setup time
tSU; DAT
250(3)
—
100(3) (4)
—
ns
Setup time for STOP condition
tSU; STO
4.0
—
0.6
—
µs
Bus-free time between STOP and START condition
tBUF
4.7
—
1.3
—
µs
Pulse width of spikes that must be suppressed by the input filter
tSP
N/A
N/A
0
50
ns
1.
2.
3.
4.
The master mode I2C deasserts ACK of an address byte simultaneously with the falling edge of SCL. If no slaves acknowledge this address byte, a negative hold time can result, depending on the edge rates of the SDA and SCL lines.
The maximum tHD; DAT must be met only if the device does not stretch the LOW period (tLOW) of the SCL signal.
Setup time in slave-transmitter mode is one IPBus clock period, if the TX FIFO is empty.
A fast-mode I2C bus device can be used in a Standard mode I2C bus system, but the requirement tSU; DAT ≥ 250 ns must then be met. This will automatically be the case if the device does not stretch the LOW period of the SCL signal. If such a device does stretch the LOW period of the SCL signal, it must
output the next data bit to the SDA line trmax + tSU; DAT = 1000 + 250 = 1250 ns (according to the Standard-mode I2C bus specification) before the SCL
line is released.
MMA955xL
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4.14
Slave SPI Timing
The following table describes the timing requirements for the SPI system. The “#” column refers to the numbered time period in
Figure 10.
Table 14. Slave SPI timing
#
Function
Symbol
Min
Max
Unit
fop
0
FOPH/4
Hz
SCLK period
tSCLK
4
—
tCYCH
—
Operating frequency
1
2
Enable lead time
tLead
0.5
—
tCYCH
3
Enable lag time
tLag
0.5
—
tCYCH
4
Clock (SCLK) high or low time
tWSCLK
200
—
ns
5
Data-setup time (inputs)
tSU
15
—
ns
6
Data-hold time (inputs)
tHI
25
—
ns
7
Access time
ta
—
25
ns
8
SDO-disable time
tdis
—
25
ns
9
Data valid (after SCLK edge)
tv
—
25
ns
10
Data-hold time (outputs)
tHO
0
—
ns
11
Rise time
Input
Output
tRI
tRO
—
—
25
25
ns
ns
12
Fall time
Input
Output
tFI
tFO
—
—
25
25
ns
ns
SS
(INPUT)
1
11
12
3
SCLK
(INPUT)
2
4
4
8
7
SDO
(OUTPUT)
9
SLAVE
5
SDI
(INPUT)
MSB OUT
BIT 6 . . . 1
<
10
10
SLAVE LSB OUT
SEE
NOTE
6
MSB IN
BIT 6 . . . 1
LSB IN
NOTE:
1. Not defined but normally MSB of character just received.
Figure 10. SPI slave timing
MMA955xL
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4.15
Flash Parameters
The MMA955xL platform has 16 KB of internal flash memory. There are ROM functions that allow reading, erasing, and
programming of that memory. Chip supply voltage of 1.8 V is sufficient for the flash programming voltage.
The lower portion of the flash memory is occupied by Freescale factory firmware and is protected so that a user cannot erase it.
The size of the available flash memory varies between the different devices in the MMA955xL product family, as shown in the
following figure.
00$ /
0RWLRQVHQVLQJ
SODWIRUP
00$ /
+LJKIOH[LELOLW\
SODWIRUP
00$ /
3HGRPHWHU
SODWIRUP
00$ /
*HVWXUHVHQVLQJ
SODWIRUP
.%
.%
.%
.%
.%
%DVHILUPZDUH
*HVWXUHILUPZDUH
3HGRPHWHUILUPZDUH
)DFWRU\ILUPZDUH
8VHUILUPZDUH
)RXQGDWLRQILUPZDUH
Figure 11. Flash memory map for devices
The smallest block of memory that can be written is 4 bytes and those 4 bytes must be aligned on a 4-byte boundary. The largest
block of memory that can be programmed is 128 bytes and the block must start at a 128-byte boundary.
Flash programming blocks must start on a 4-byte boundary and cannot cross a 128-byte page boundary.
Table 15. Flash parameters
Parameter
Word depth
Row size
Value
4096
128 bytes
Page erase size (Erase block size)
4 rows = 512 bytes
Maximum page programming size
1 row = 128 bytes
Minimum word programming size
Memory organization
Endurance
Data retention
4 bytes
4096 x 32 bits = 16 KB total
20,000 cycles minimum
> 100 years, at room temperature
MMA955xL
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5
Package Information
The MMA955xL platform uses a 16-lead LGA package, case number 2094.Use the following link for the latest diagram of the
package: www.freescale.com/files/shared/doc/package_info/98ASA00287D.pdf
5.1
Footprint and pattern information
Pin 16
Pin 1 ID
Pin 1
Package pad size
0.24mm x 0.35 mm
Figure 12. Package bottom view
PCB land extension
From the edge of the package
PCB land pad
PCB pad distance
to package edge
Package size (Measurements in mm)
Figure 13. Package overlaid on PCB footprint diagram (top view)
MMA955xL
Sensors
Freescale Semiconductor, Inc.
23
PCB land pad size
0.65 mm x 0.25 mm
Solder mask opening
0.777 mm x 1.377 mm
(PCB land + 0.0637 mm
larger all around.
Remove slivers between pads.)
Solder stencil opening
0.62 mm x 0.22 mm
(PCB land - 0.015 mm
smaller all around)
Figure 14. Recommended PCB footprint
5.2
Marking
!"!!
MMA955xL
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5.3
Tape and reel information
Figure 15. Tape dimensions
The devices are oriented on the tape as shown in Figure 16. The dot marked on each device indicates pin 1.
Pin 1
Direction
to unreel
Barcode label
side of reel
Figure 16. Tape and reel orientation
MMA955xL
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Freescale Semiconductor, Inc.
25
6
Revision History
Revision
number
Revision
date
0
06/2011
Initial release of document.
1
10/2011
•
•
•
•
Added the MMA9559L device.
Added a features table and a package land diagram figure.
Modified block diagram
Inserted flash memory map figure
2
5/2013
•
•
•
•
•
•
•
•
Removed MMA9550LT and MMA9551LT from Ordering Information table
Added Pedometer to MMA9553LR throughout
Added list of links to Related Documentation
User RAM available for MMA9553 was 200 bytes
Removed mobile phones from Typical Applications
Removed Dead reckoning from Typical Applications/Fleet monitoring, tracking
Added a pull-up resistor to Pin 2 of Figures 7, 8, and 9
Removed the Conditions column from Table 5
3
9/2013
• Added Marking, Tape and reel, and Package dimensions
• Moved Footprint and pattern information from Package diagrams to Package Information
3.1
5/2015
•
•
•
•
Description of changes
Changed part number from MMA955xL to MMA9550L, MMA9551L, MMA9553L, and MMA9559L
Table 2, MMA9553L, User flash available changed from 1.5 KB to 1.0 KB
Table 2, MMA9553L, changed 304 bytes to 420 bytes in user RAM available
Section 1, Added sentence stating that MMA9555L data and functions are in a separate data
sheet
• Section 3.3, Master I2C: SDA1 and SCL1: was ...master-I2C clock and data signals...
• Figures 4, 5, and 6, Changed SBB to SSB
• Section 3.4.3, added note
MMA955xL
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Freescale Semiconductor, Inc.
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Freescale reserves the right to make changes without further notice to any products
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disclaims any and all liability, including without limitation consequential or incidental
damages. “Typical” parameters that may be provided in Freescale data sheets and/or
specifications can and do vary in different applications, and actual performance may
vary over time. All operating parameters, including “typicals,” must be validated for
each customer application by customer’s technical experts. Freescale does not convey
any license under its patent rights nor the rights of others. Freescale sells products
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address: freescale.com/salestermsandconditions.
Freescale, the Freescale logo, CodeWarrior, and the Energy Efficient Solutions logo,
are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. All other
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© 2011, 2013, 2015 Freescale Semiconductor, Inc.
Document Number: MMA955xL
Rev. 3.1, 5/2015
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