ADIS16407/PCBZ Analog Devices Inc, ADIS16407/PCBZ Datasheet - Page 18

• Manufacturer Part Number: ADIS16407/PCBZ
• Description: ADIS16407/PCB EVAL. BD.
• Manufacturer: Analog Devices Inc
• Series: iMEMS®, iSensor™r

Specifications of ADIS16407/PCBZ

• Sensor Type: Accelerometer, Gyroscope, Magnetometer, 3 Axis
• Sensing Range: ±18g, ±75°/sec, ±150°/sec, ±300°/sec, ±2.5gauss
• Interface: SPI Serial
• Sensitivity: 3.33mg/LSB, 0.0125 ~ 0.05°/sec/LSB, 0.5mgauss/LSB
• Voltage - Supply: 4.75 V ~ 5.25 V
• Embedded: No
• Utilized Ic / Part: ADIS16407
• Kit Application Type: Sensing - Motion / Vibration / Shock
• Application Sub Type: Shock Sensor
• Silicon Manufacturer: Analog Devices
• Silicon Core Number: ADIS16407
• Kit Contents: Board, Manual
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

ADIS16407
DIGITAL PROCESSING CONFIGURATION
Table 45. Digital Processing Registers
Register Name
SMPL_PRD
SENS_AVG
SAMPLE RATE
The internal sampling system produces new data in the output
data registers at a rate of 819.2 SPS. The SMPL_PRD register in
Table 46 provides two functional controls that affect sampling
and register update rates. SMPL_PRD[12:8] provides a control
for reducing the update rate, using an averaging filter with a deci-
mated output. These bits provide a binomial control that divides
the data rate by a factor of 2 every time this number increases
by 1. For example, set SMPL_PRD[15:8] = 0x04 (DIN = 0xBB04)
to set the decimation factor to 16. This reduces the update rate
to 51 SPS and the bandwidth to 25 Hz.
Table 46. SMPL_PRD (Base Address = 0x3A), Read/Write
Bits
[15:13]
[12:8]
[7:1]
[0]
INPUT CLOCK CONFIGURATION
SMPL_PRD[0] provides a control for synchronizing the internal
sampling to an external clock source. Set SMPL_PRD[0] = 0
(DIN = 0xBA00) and GPIO_CTRL[3] = 0 (DIN = 0xB600) to
enable the external clock. See Table 2 and Figure 4 for timing
information.
DIGITAL FILTERING
The SENS_AVG register in Table 47 provides user controls for
the low-pass filter. This filter contains two cascaded averaging
filters that provide a Bartlett window, FIR filter response (see
Figure 19). For example, set SENS_AVG[2:0] = 100 (DIN = 0xBC04)
to set each stage to 16 taps. When used with the default sample
rate of 819.2 SPS and zero decimation (SMPL_PRD[15:8] = 0x00),
this value reduces the sensor bandwidth to approximately 16 Hz.
Description (Default = 0x0001)
Not used
D, decimation rate setting, binomial, see Figure 19
Not used
Clock
1 = internal 819.2 SPS
0 = external
0x3A
Address
0x3C
LOW-PASS, TWO-POLE (404Hz, 757Hz)
SENSOR
MEMS
LOW-PASS, SINGLE-POLE (330Hz)
ACCELEROMETERS
Sample rate control
Digital filtering and range control
Description
GYROSCOPES
LOW-PASS
FILTER
330Hz
Figure 19. Sampling and Frequency Response Block Diagram
EXTERNAL CLOCK ENABLED
BY SMPL_PRD[0] = 0
819.2SPS
ADC
CLOCK
Rev. B | Page 18 of 24
N
1
B
B = SENS_AVG[2:0]
N
N
BARTLETT WINDOW
n = 1
B
B
N
= 2
= NUMBER OF TAPS
B
DYNAMIC RANGE
The SENS_AVG[10:8] bits provide three dynamic range settings
for this gyroscope. The lower dynamic range settings (±75°/sec
and ±150°/sec) limit the minimum filter tap sizes to maintain
resolution. For example, set SENS_AVG[10:8] = 010 (DIN =
0xBD02) for a measurement range of ±150°/sec. Because this
setting can influence the filter settings, program SENS_AVG[10:8]
before programming SENS_AVG[2:0] if more filtering is required.
Table 47. SENS_AVG (Base Address = 0x3C), Read/Write
Bits
[15:11]
[10:8]
[7:3]
[2:0]
x(n)
(PER STAGE)
FIR FILTER
B
–100
–120
–140
–20
–40
–60
–80
N
1
Figure 18. Bartlett Window, FIR Filter Frequency Response
0.001
B
0
n = 1
Description (Default = 0x0402)
Not used
Measurement range (sensitivity) selection
100 = ±300°/sec (default condition)
010 = ±150°/sec, filter taps ≥ 4 (Bits[2:0] ≥ 0x02)
001 = ±75°/sec, filter taps ≥ 16 (Bits[2:0] ≥ 0x04)
Not used
Filter Size Variable B
Number of taps in each stage; N
See Figure 18 for filter response
N
B
x(n)
N = 2
N = 4
N = 16
N = 64
DECIMATION
D = SMPL_PRD[12:8]
N
N
N
AVERAGE/
D
D
1
(Phase Delay = N Samples)
D
FILTER
= 2
= NUMBER OF TAPS
n = 1
N
D
0.01
D
x(n)
FREQUENCY (
÷N
D
f
/
f
S
)
0.1
B
= 2
B
1