Cheat Sheet: Accelerometer Datasheet Specifications
Specification Tricky Examples
Accelerometer Type MEMS (or maybe not listed)
There are three main types of accelerometers: capacitive MEMS, Generally means it’s capacitive.
piezoelectric, and piezoresistive. The datasheet should tell you IEPE
what type it uses because the accelerometer type defines which
Integrated Electronic Piezoelectric.
applications it works best for.
Frequency Response or Bandwidth 2 to 4000 Hz ±3dB
A tolerance band of sensitivity deviation across a range of This means that the accelerometer output can have an error as
frequencies. Be certain that the low frequency goes to 0 hertz much as +40% to -30% from nominal over the frequency range
if you need a DC response for integration or measuring “slow” of 2 to 4000 Hz. There should be a provided plot to clarify the
accelerations (think human motion type). performance across the frequency range.
Sensitivity 3.0 pC/g
Defines the rate at which the sensor converts mechanical energy This is a charge mode piezoelectric accelerometer that will need
to an electrical signal. This information needs to be communi- a signal conditioner so that a voltage output can be measured
cated to the data acquisition and/or signal conditioning system with your DAQ system.
to accurately determine the amplitude of the data output.
Measurement Range Not provided but sensitivity is defined as 50 mV/g
Specifies the acceleration range the accelerometer can measure. The measurement range can be calculated by dividing the DC
It is likely to be able to handle higher accelerations outside this voltage supply (should be listed on the datasheet) by the sensi-
range. Be sure to select an accelerometer with a measurement tivity. For example, say we have a 10 volt supply, the measure-
range 2 to 4 times that of what you are looking to actually mea- ment range is ±100g (10/0.05/2).
sure to enable measurement of unanticipated events.
Noise 100 µg/√Hz from 2 Hz to 10 kHz
Defines the lowest level of acceleration the accelerometer can To calculate the RMS value of this noise the spectral noise must
provide before the data is just electrical noise, i.e. no conclusions be squared, then integrate over the frequency range and take
can be drawn from the data. the square root of the result.
Resolution 14-bit
This defines the smallest measurable acceleration increment. There are 2^14 (16,384) bins, so for a ±50g accelerometer the
Most often specified in bits which defines the number of parts smallest increment is 0.006g.
the signal can be divided into.
Filtering 5th order Butterworth
If you are looking at a digital part or a system some filtering will Butterworth is the type of filter. The order defines the frequen-
be required to prevent aliasing. The filter type, order, and fre- cy response angle, the higher the better to adequately filter out
quency should be provided; if not, assume there is no filtering. unwanted frequencies.
Temperature Sensitivity -0.3%/°C
Accelerometers are mechanical systems and as such they will be The sensitivity deviates negative 0.3% per degree difference
influenced by temperature. This specification defines how sen- from the reference temperature. For example an accelerom-
sitive the accelerometer is to temperature. If the accelerometer eter calibrated at 25C will have a sensitivity 16.5% higher than
will be in an environment with a wide temperature range, this nominal at 80C.
parameter is very important.
Transverse Sensitivity <10%
Defines how sensitive the accelerometer is to accelerations Less than 10% of the acceleration amplitude in the X axis for
orthogonal (90 degrees) to the primary axis. example will be measured by the Z axis accelerometer channel.
Triaxial Not Listed
Indicates that the accelerometer can measure in all 3 axes. Assume it’s single-axis.
Mide Technology | www.mide.com | blog.mide.com
Mide Technology | www.mide.com | blog.mide.com
Cheat Sheet: Accelerometer Datasheet Specifications
Specification Tricky Examples
Accelerometer Type MEMS (or maybe not listed)
There are three main types of accelerometers: capacitive MEMS, Generally means it’s capacitive.
piezoelectric, and piezoresistive. The datasheet should tell you IEPE
what type it uses because the accelerometer type defines which
Integrated Electronic Piezoelectric.
applications it works best for.
Frequency Response or Bandwidth 2 to 4000 Hz ±3dB
A tolerance band of sensitivity deviation across a range of This means that the accelerometer output can have an error as
frequencies. Be certain that the low frequency goes to 0 hertz much as +40% to -30% from nominal over the frequency range
if you need a DC response for integration or measuring “slow” of 2 to 4000 Hz. There should be a provided plot to clarify the
accelerations (think human motion type). performance across the frequency range.
Sensitivity 3.0 pC/g
Defines the rate at which the sensor converts mechanical energy This is a charge mode piezoelectric accelerometer that will need
to an electrical signal. This information needs to be communi- a signal conditioner so that a voltage output can be measured
cated to the data acquisition and/or signal conditioning system with your DAQ system.
to accurately determine the amplitude of the data output.
Measurement Range Not provided but sensitivity is defined as 50 mV/g
Specifies the acceleration range the accelerometer can measure. The measurement range can be calculated by dividing the DC
It is likely to be able to handle higher accelerations outside this voltage supply (should be listed on the datasheet) by the sensi-
range. Be sure to select an accelerometer with a measurement tivity. For example, say we have a 10 volt supply, the measure-
range 2 to 4 times that of what you are looking to actually mea- ment range is ±100g (10/0.05/2).
sure to enable measurement of unanticipated events.
Noise 100 µg/√Hz from 2 Hz to 10 kHz
Defines the lowest level of acceleration the accelerometer can To calculate the RMS value of this noise the spectral noise must
provide before the data is just electrical noise, i.e. no conclusions be squared, then integrate over the frequency range and take
can be drawn from the data. the square root of the result.
Resolution 14-bit
This defines the smallest measurable acceleration increment. There are 2^14 (16,384) bins, so for a ±50g accelerometer the
Most often specified in bits which defines the number of parts smallest increment is 0.006g.
the signal can be divided into.
Filtering 5th order Butterworth
If you are looking at a digital part or a system some filtering will Butterworth is the type of filter. The order defines the frequen-
be required to prevent aliasing. The filter type, order, and fre- cy response angle, the higher the better to adequately filter out
quency should be provided; if not, assume there is no filtering. unwanted frequencies.
Temperature Sensitivity -0.3%/°C
Accelerometers are mechanical systems and as such they will be The sensitivity deviates negative 0.3% per degree difference
influenced by temperature. This specification defines how sen- from the reference temperature. For example an accelerom-
sitive the accelerometer is to temperature. If the accelerometer eter calibrated at 25C will have a sensitivity 16.5% higher than
will be in an environment with a wide temperature range, this nominal at 80C.
parameter is very important.
Transverse Sensitivity <10%
Defines how sensitive the accelerometer is to accelerations Less than 10% of the acceleration amplitude in the X axis for
orthogonal (90 degrees) to the primary axis. example will be measured by the Z axis accelerometer channel.
Triaxial Not Listed
Indicates that the accelerometer can measure in all 3 axes. Assume it’s single-axis.
Mide Technology | www.mide.com | blog.mide.com
