MMA7660FCR1 Freescale Semiconductor, MMA7660FCR1 Datasheet - Page 12

• Manufacturer Part Number: MMA7660FCR1
• Description: Board Mount Accelerometers 3-Axis Digital Out Accelerometer
• Manufacturer: Freescale Semiconductor

Specifications of MMA7660FCR1

• Sensing Axis: X, Y, Z
• Acceleration: 1.5 g
• Digital Output - Number Of Bits: 6 bit
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Digital Output - Bus Interface: 12 C
• Sensitivity: 21.33 count/g
• Package / Case: DFN-10
• Output Type: Digital
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Orientation Detection
Orientation Detection Logic
Mobile Phone/PDA/ PMP. The tilt orientation of the device is in 3 dimensions and is identified in its last known static position. This
enables a product to set its display orientation appropriately to either portrait/landscape mode, or to turn off the display if the
product is placed upside down. The sensor provides six different positions including: Left, Right, Up, Down, Back, and Front,
shown in
measurement interval, it computes new values for Left, Right, Up, Down, Back, and Front but it does not automatically update
these bits in the TILT (0x03) register. These values are updated depending on the debounce filter settings (SR Register 0x08)
configured by the customer.
following bits in the SR (0x08) register, FILT [2:0]. Please see below for a more detailed explanation of how the FILT [2:0] works
in conjunction with updating the TILT (0x03) register:
Table 7. Orientation Detection Logic of when Interrupt will Occur
Sensors
Freescale Semiconductor
Orientation
•
•
MMA7660FC gives the customer the capability to do orientation detection for such applications as Portrait/Landscape in
In order to give the customer the ability to configure the debounce filter, specific to there application, they can change the
Shake
Down
Right
Front
Back
If FILT [2:0] = 000, then the new values for Left, Right, Up, Down, Back, and Front are updated in the TILT (0x03) register
(PoLa [2:0] and BaFro [1:0]) after every reading without any further analysis.
If FILT [2:0] = 001 – 111, then the sensor requires the computed values for Left, Right, Up, Down, Back, and Front to be the
same from 1-7 consecutive readings (depending on the value in FILT [2:0], before updating the values stored in TILT (0x03)
register (PoLa [2:0] and BaFro [1:0]). The debounce counter is reset after a mismatched reading or the TILT (0x03) register
is updated (if the orientation condition is met).
Left
Up
Table
7. In Active Mode the data is processed and updates the orientation positions in the TILT (0x03) register. At each
|Z| < 0.8g and |X| > |Y| and X < 0
|Z| < 0.8g and |X| > |Y| and X > 0
|X| > +1.3g
Figure 6. Orientation Detection Logic in 3-Dimensional Space
Xg
Left
Left
or
|Z| < 0.8g and |Y| > |X| and Y < 0
|Z| < 0.8g and |Y| > |X| and Y > 0
Back
Back
Front
Front
Down
Down
|Y| > +1.3g
Up
Up
Yg
Right
Right
or
Z < -0.25g
Z > 0.25g
|Z| > +1.3g
Zg
MMA7660FC
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