LFSTBEB865X Freescale Semiconductor, LFSTBEB865X Datasheet - Page 44

• Manufacturer Part Number: LFSTBEB865X
• Description: Acceleration Sensor Development Tools EVB FOR MMA865xQ
• Manufacturer: Freescale Semiconductor

Specifications of LFSTBEB865X

• Rohs: yes
• Tool Is For Evaluation Of: MMA8652FC, MMA8653FC
• Acceleration: 2 g, 4 g, 8 g
• Sensing Axis: Triple Axis
• Interface Type: USB

44
Real-Time Output
Screen Frame
(continued)
Offset Calibration
Auto Calibrate
Self Test
Table 13. Full-System Evaluation – Main screen (Continued)
screen group
Element or
MMA865xFC Sensor Toolbox User’s Guide, Rev. 0
• XCal Counts
• YCal Counts
• ZCal Counts
Write
Makes the device calculate the necessary values for the X, Y, and ZCal fields.
The calibration is done with an 8g Dynamic Range and a Sample Rate of
1.563 Hz.
Before clicking the Auto Calibrate button:
• Place the device on a flat, stationary surface.
• Enable the Standby button (in the Operation Mode screen).
Enable
Button
description
Element or
Specifies the values to be added to the device’s output
measurements, to correct for any data inaccuracies.
The calibration values will need to be calculated differently,
varying with the Dynamic Range setting. If the device is
reading 21 counts in the X-axis when sitting flat on a table
(should be 0 counts), then the following correct values are
required for the indicated Dynamic Range setting:
Writes the values in the XCal, YCal, and ZCal text boxes
into the calibration register.
Initiates a test where the device applies a small
electrostatic force to the sensor, to simulate a small
acceleration.
If you leave this box checked during tests, then all
measurements will be offset by this simulated acceleration.
• 2g – Divide the count by 4 before storing it in the
• 4g – you must divide the number by 2, before storing it
• 8g – No correction is required.
register.
It is not possible to store fractional values, so in this case
2
XCal field.
in the register.
In the above situation, you would place (2
either -10 or -11 in the XCal field.
1
/
4
= 5.25, and you must round down and put -5 in the
Description
Freescale Semiconductor, Inc.
1
/
2
= 10.5)