XMMA1000P XMMA2000W

2

Motorola Sensor Device Data

Rating

Symbol

Value

Unit

Powered Acceleration (all axis)

Gpd

500

g

Unpowered Acceleration (all axis)

Gupd

2000

g

Supply Voltage

VDD

–0.3 to +7.0

V

Drop Test(1)

Ddrop

1.2

m

Storage Temperature Range

Tstg

– 40 to +105

°C

Characteristic

Symbol

Min

Typ

Max

Unit

Supply Voltage(2)

VDD

4.75

5.0

5.25

V

Supply Current

IDD

1.0

4.0

5.0

mA

Operating Temperature Range

TA

–40

—

+85

°C

NOTES:

1. Dropped onto concrete surface from any axis.

2. Within the supply range of 4.75 and 5.25 volts, the device operates as a fully calibrated linear accelerometer. Beyond these supply limits

the device may operate as a linear device but is not guaranteed to be in calibration.

ELECTRO STATIC DISCHARGE (ESD)

Due to the technological advancing semiconductor indus-

try, it has now become increasingly important for semicon-

ductor manufacturers, users of semiconductors and other

electronic components to fully understand the nature and

sources of ESD. More importantly, a thorough understanding

of its impact on quality and reliability must be understood.

Whereas the Motorola accelerometers contain internal

2kV ESD protection circuitry, extra precaution must be taken

by the user to protect the chip from ESD. A charge of over

2000 volts can accumulate on the human body or associated

Automated Test Equipment (ATE). A charge of this magni-

tude can alter the performance or cause failure of the chip.

When proper ESD precautions are followed the discharges

will not be detrimental to the chips performance.

FREQUENTLY ASKED QUESTIONS

Q. What is the g–cell?

A. The g–cell is the acceleration transducer within the accel-

erometer device. It is hermetically sealed at the wafer level to

ensure a contaminant free environment, resulting in superior

reliability performance.

Q. What does the output typically interface with?

A. The accelerometer device is designed to interface with an

analog to digital converter available on most microcontrol-

lers. The output has a 2.5 V DC offset, therefore positive and

negative acceleration is measurable.

Q. What is the orientation of the g–force in relation to the

output voltage?

A. The accelerometer responds to g forces perpendicular to

the plane of the package. For acceleration directed onto the

top of the package, the output voltage will increase above the

nominal 2.5 V. For acceleration directed away from the top of

the package, the output will decrease below 2.5 V. Refer to

the “Positive Acceleration Sensing Direction’’ diagram on

page 7.

Q. What is the resonant frequency of the g–cell?

A. The accelerometer’s g–cell is overdamped. The first reso-

nant mode of the package is 10 kHz for the DIP and 5 kHz for

the Wingback.

Q. What is ratiometricity?

A. Ratiometricity is the sensors ability to track changes in

supply voltage. This is a key feature when interfacing to a

microcontroller or an A/D converter. Ratiometricity allows for

system level cancellation of supply induced errors in the ana-

log to digital conversion process. Refer to the Special Fea-

tures section under the Principle of Operation for more

information.

Q. Is the accelerometer device sensitive to electrostatic

discharge (ESD)?

A. Yes . . . the SENSEON accelerometer should be handled

like other CMOS technology devices.

Q. Can the g–cell part “latch’’?

A. No, overrange stops have been designed into the g–cell

to prevent latching. (Latching is when the middle plate of the

g–cell sticks to either the upper or lower plate.)