ADIS16003PCB AD [Analog Devices], ADIS16003PCB Datasheet - Page 11

• Manufacturer Part Number: ADIS16003PCB
• Manufacturer: AD [Analog Devices]

THEORY OF OPERATION
The ADIS16003 is a low cost, low power, complete dual-axis
accelerometer with an integrated serial peripheral interface
(SPI) and an integrated temperature sensor whose output is also
available on the SPI interface. The ADIS16003 is capable of
measuring acceleration with a full-scale range of ±1.7 g
(minimum). It can also measure both dynamic acceleration
(vibration) and static acceleration (gravity).
SELF-TEST
The ST pin controls the self-test feature. When this pin is set to
V
ometer. The resulting movement of the beam allows the user to
test if the accelerometer is functional. The typical change in
output is 750 mg (corresponding to 614 LSB) for V
This pin may be left open-circuit or connected to common in
normal use. The ST pin should never be exposed to voltage
greater than V
condition cannot be guaranteed (for example, multiple supply
voltages present), a low V
is recommended.
SERIAL INTERFACE
The serial interface on the ADIS16003 consists of five wires, CS ,
TCS , SCLK, DIN, and DOUT, with the temperature sensor’s
serial interface in parallel with the accelerometer’s serial
interface. The CS and TCS are used to select the accelerometer
or temperature sensor outputs, respectively. CS and TCS cannot
be active at the same time.
The SCLK input accesses data from the internal data registers.
CC
DIGITAL OUTPUT (IN LSBs)
, an electrostatic force is exerted on the beam of the acceler-
9
1
X-AXIS: 2048
Y-AXIS: 2867
8
2
7
3
Figure 23. Output Response vs. Orientation
CC
+ 0.3 V. If the system design is such that this
DIGITAL OUTPUT (IN LSBs)
DIGITAL OUTPUT (IN LSBs)
12
10
4
6
X-AXIS: 1229
Y-AXIS: 2048
X-AXIS: 2867
Y-AXIS: 2048
F
Not to Scale
Top View
clamping diode between ST and V
11
11
5
5
10
12
6
4
DIGITAL OUTPUT (IN LSBs)
3
7
X-AXIS: 2048
Y-AXIS: 1229
DIGITAL OUTPUT (IN LSBs)
2
8
X-AXIS: 2048
Y-AXIS: 2048
CC
1
9
= 5.0 V.
Rev. 0 | Page 11 of 16
CC
ACCELEROMETER SERIAL INTERFACE
Figure 3 shows the detailed timing diagram for serial inter-
facing to the accelerometer in the ADIS16003. The serial clock
provides the conversion clock. CS initiates the data transfer and
conversion process and frames the serial data transfer for the
accelerometer output. The accelerometer output is sampled on
the second rising edge of the SCLK input after the falling edge
of the CS . The conversion requires 16 SCLK cycles to complete.
The rising edge of
remains low, the next digital conversion is initiated. The details
for the control register bit functions are shown in Table 6.
Accelerometer Control Register
MSB
DONTC
Table 6. Accelerometer Control Register Bit Functions
Bit
7
6, 5,
4
3
2
1
0
Power Down
By setting PM0 to one when updating the accelerometer control
register, the ADIS16003 goes into a shutdown mode. The
information stored in the control register is maintained during
shutdown. The ADIS16003 changes modes as soon as the
control register is updated. If the part is in shutdown mode and
PM0 is changed to zero, then the part powers up on the
sixteenth SCLK rising edge.
ADD0
By setting ADD0 to zero when updating the accelerometer
control register, the x-axis output is selected. By setting ADD0
to one, the y-axis output is selected.
ZERO
ZERO is defined as the logic low level.
ONE
ONE is defined as the logic high level.
DONTC
DONTC is defined as don’t care; can be a low or high logic level.
Mnemonic
DONTC
ZERO
ADD0
ONE
ZERO
PM0
ZERO
ZERO
CS
Comments
Don’t care. Can be one or zero.
These bits should be held low.
This address bit selects the x-axis or y-axis
outputs. Zero selects the x-axis; one selects
the y-axis.
This bit should be held high.
This bit should be held low.
This bit selects the operation mode for the
accelerometer; set to zero for normal
operation and one for power down mode.
puts the bus back into three-state. If
ZERO
ADD0
ONE
ADIS16003
ZERO
CS
LSB
PM0