mma7361l Freescale Semiconductor, Inc, mma7361l Datasheet - Page 5

• Manufacturer Part Number: mma7361l
• Description: ?1.5g, ?6g Three Axis Low-g Micromachined Accelerometer
• Manufacturer: Freescale Semiconductor, Inc

Table 4. Pin Descriptions
Pin No.
Sensors
Freescale Semiconductor
Pin Descriptions
10
11
12
13
14
1
2
3
4
5
6
7
8
9
Figure 5. Accelerometer with Recommended
V DD
Pin Name
0g-Detect
Self Test
g-Select
Sleep
X
Y
0.1 μF
Z
V
V
N/C
N/C
N/C
N/C
NC
OUT
OUT
OUT
SS
DD
Logic
Input
Logic
Input
Logic
Input
Figure 4. Pinout Description
X
Y
Z
N/C
V
OUT
OUT
OUT
V
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
Linear Freefall digital logic output signal
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
MMA7361L
Sleep
N/C
0g-Detect
Y OUT
Z OUT
X OUT
Description
Self Test
N/C
N/C
g-Select
0g-Detect
N/C
9
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
0g-Detect
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
A/D
A/D
V
P0
P1
P2
P3
RH
IN
IN
IN
OUT
MMA7361L
Figure
, Y
V
OUT
V
DD
SS
6.
and
C
C
5