MMA8450QT Freescale Semiconductor, MMA8450QT Datasheet - Page 19

• Manufacturer Part Number: MMA8450QT
• Description: Board Mount Accelerometers 12bit 3-Axis FIFO HPF PL
• Manufacturer: Freescale Semiconductor

Specifications of MMA8450QT

• Sensing Axis: X, Y, Z
• Acceleration: 2 g, 4 g, 8 g
• Digital Output - Number Of Bits: 12 bit
• Supply Voltage (max): 1.89 V
• Supply Voltage (min): 1.71 V
• Supply Current: 3 uA
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Shutdown: Yes
• Sensitivity: 0.976 mg/digit, 1.953 mg/digit, 3.906 mg/digit
• Package / Case: QFN-16
• Output Type: Digital
• Package Type: QFN
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Product Depth (mm): 3mm
• Product Height (mm): 1mm
• Product Length (mm): 3mm
• Mounting: Surface Mount
• Pin Count: 16
• Acceleration Range: ± 2g, ± 4g, ± 8g
• No. Of Axes: 3
• Ic Interface Type: I2C, Serial
• Sensor Case Style: QFN
• No. Of Pins: 16
• Supply Voltage Range: 1.71V To 1.89V
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Multiple Byte Write
Therefore, after following the steps of a single byte write, multiple bytes of data can be written to sequential registers after each
MMA8450Q acknowledgment (ACK) is received.
Table 10. I
Sensors
Freescale Semiconductor
< Single Byte Read >
< Multiple Byte Read >
< Single Byte Write >
< Multiple Byte Write >
Master
Master
Master
Master
Master
Slave
Slave
Slave
Slave
Slave
The MMA8450Q automatically increments the received register address commands after a write command is received.
Command
Legend
ST: Start Condition
SR: Repeated Start Condition
Read
Write
Read
Write
2
C device Address Sequence
ST
ST
ST
ST
Data [7:0]
Device Address [6:0]
Device Address [6:0]
Device Address [6:0]
Device Address [6:0]
Device Address
AK
001110
001110
001110
001110
[6:1]
SP: Stop Condition
AK: Acknowledge
W
W
W
W
Data [7:0]
AK
AK
AK
AK
Figure 11. I
Register Address [7:0]
Register Address [7:0]
Register Address [7:0]
Register Address [7:0]
SA0
[0]
0
0
1
1
AK
2
C Timing Diagram
NAK: No Acknowledge
R: Read = 1
Data [7:0]
Device Address
AK
AK
AK
AK
0x1D
0x1D
0x1C
0x1C
[6:0]
SR Device Address [6:0]
SR Device Address [6:0] R
NAK
Data [7:0]
Data [7:0]
SP
R/W
W: Write = 0
1
0
1
0
AK
AK
R
SP
AK
AK
Data [7:0]
8-bit Final Value
Data [7:0]
Data [7:0]
0x3B
0x3A
0x39
0x38
MMA8450Q
AK
AK
NAK SP
19