MMA7331LT Freescale, MMA7331LT Datasheet - Page 5

• Manufacturer Part Number: MMA7331LT
• Manufacturer: Freescale

Specifications of MMA7331LT

• Package Type: LGA
• Operating Supply Voltage (min): 2.2V
• Operating Supply Voltage (typ): 2.5/3.3V
• Operating Supply Voltage (max): 3.6V
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Product Depth (mm): 3mm
• Product Height (mm): 1mm
• Product Length (mm): 5mm
• Mounting: Surface Mount
• Pin Count: 14
• Lead Free Status / RoHS Status: Compliant

Sensors
Freescale Semiconductor
Table 4. Pin Descriptions
Pin Descriptions
Pin No. Pin Name
10
11
12
13
14
1
2
3
4
5
6
7
8
9
Figure 5. Accelerometer with Recommended
Self Test
g-Select
V DD
Sleep
X
Y
Z
V
V
N/C
N/C
N/C
N/C
N/C
N/C
OUT
OUT
OUT
0.1 μF
SS
DD
Logic
Input
Logic
Input
Logic
Input
X
Y
Z
Figure 4. Pinout Description
V
N/C
V
OUT
OUT
OUT
DD
SS
Connection Diagram
No internal connection
Leave unconnected
X direction output voltage
Y direction output voltage
Z direction output voltage
Power Supply Ground
Power Supply Input
Logic input pin to enable product or Sleep Mode
No internal connection
Leave unconnected
No internal connection
Leave unconnected
Logic input pin to select g level
Unused for factory trim
Leave unconnected
Unused for factory trim
Leave unconnected
Input pin to initiate Self Test
Unused for factory trim
Leave unconnected
10
13
6
5
7
g-Select
Self Test
V DD
V SS
Sleep
Top View
Sleep
MMA7331L
N/C
X OUT
Y OUT
Z OUT
Description
Self Test
N/C
N/C
g-Select
N/C
N/C
2
3
4
3.3 nF
3.3 nF
3.3 nF
BASIC CONNECTIONS
PCB Layout
NOTES:
Figure 6. Recommended PCB Layout for Interfacing
1. Use 0.1 µF capacitor on V
2. Physical coupling distance of the accelerometer to
3. Place a ground plane beneath the accelerometer to
4. Use a 3.3nF capacitor on the outputs of the
5. PCB layout of power and ground should not couple
6. Accelerometer and microcontroller should not be a
7. A/D sampling rate and any external power supply
8. 10MΩ or higher is recommended on X
source.
the microcontroller should be minimal.
reduce noise, the ground plane should be attached to
all of the open ended terminals shown in
accelerometer to minimize clock noise (from the
switched capacitor filter circuit).
power supply noise.
high current path.
switching frequency should be selected such that
they do not interfere with the internal accelerometer
sampling frequency (11 kHz for the sampling
frequency). This will prevent aliasing errors.
Z
relationship between the internal 32 kΩ resistor and
the measurement input impedance.
Self Test
g-Select
OUT
Sleep
X
Y
Z
V
V
OUT
OUT
OUT
DD
SS
Accelerometer to Microcontroller
to prevent loss due to the voltage divider
POWER SUPPLY
C
C
C
C
DD
C
C
to decouple the power
A/D
P2
A/D
A/D
V
P0
P1
RH
IN
IN
IN
OUT
MMA7331L
Figure
, Y
V
OUT
V
DD
SS
6.
and
C
C
5