MMA8452QR1 Freescale Semiconductor, MMA8452QR1 Datasheet - Page 20

• Manufacturer Part Number: MMA8452QR1
• Description: Board Mount Accelerometers LOW G 3-AXIS 12BT EX VLT
• Manufacturer: Freescale Semiconductor

Specifications of MMA8452QR1

• Sensing Axis: X, Y, Z
• Acceleration: 2 g, 4 g, 8 g
• Digital Output - Number Of Bits: 8 bit, 12 bit
• Supply Voltage (max): 3.6 V
• Supply Voltage (min): 1.95 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Digital Output - Bus Interface: I2C
• Shutdown: Yes
• Sensitivity: 256 count/g, 512 count/g, 1024 count/g
• Package / Case: QFN-16
• Output Type: Digital
• Rohs Compliant: Yes
• Peak Reflow Compatible (260 C): Yes
• Acceleration Range: ± 2g, ± 4g, ± 8g
• No. Of Axes: 3
• Ic Interface Type: I2C
• Sensor Case Style: QFN
• No. Of Pins: 16
• Supply Voltage Range: 1.95V To 3.6V
• 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
MMA8452Q acknowledgment (ACK) is received.
Table 10. I
20
< Single Byte Read >
< Multiple Byte Read >
< Single Byte Write >
< Multiple Byte Write >
MMA8452Q
Master
Master
Master
Master
Master
Slave
Slave
Slave
Slave
Slave
The MMA8452Q automatically increments the received register address commands after a write command is received.
Command
Legend
ST: Start Condition
SR: Repeated Start Condition
Read
Read
Write
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 12. 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
0x1C
0x1C
0x1D
0x1D
[6:0]
SR
SR Device Address[6:0]
NAK
Device Address[6:0]
Data[7:0]
Data[7:0]
SP
W: Write = 0
R/W
1
0
1
0
AK
AK
R
R
SP
AK
AK
Freescale Semiconductor
Data[7:0]
8-bit Final Value
Data[7:0]
Data[7:0]
0x3B
0x3A
0x39
0x38
AK
AK
NAK SP
Sensors
SP