MEMSIC MXR7900A/C/D Rev.A

Page 1 of 6

4/09/2009

Low Cost, High Performance

±1.0 g Dual-Axis Accelerometer

with Ratiometric Outputs

MXR7900A/C/DF

FEATURES

Dual axis accelerometer fabricated on a single CMOS IC

Monolithic design with mixed mode signal processing

RoHS compliant

On-chip sensitivity compensation for temperature variations

On Demand Self Test

900mV/g sensitivity

Independent axis programmability (special order)

Resolution better than 1mg

19Hz bandwidth

>50,000 g shock survival rating

4.50V to 5.25V single supply operation

Small surface mount package, 5mm x 5mm x 2mm

APPLICATION

Automotive – Roll over sensing, VSC/EPB application

VDD

Vref

CLK

CLK

CLKTEMP

TEMP

CLK

CLK TEMP CLK

CLK

Temp

Comp.

Temp

Comp.

X axis

Y axis

CLK

Heater

Control

TEMP

No

Connection

No

Connection

Xout

Yout

Low Pass

A/D

Temperature

Sensor

Internal

Oscillator

Coarse

Gain Adj.

Fine Gain

Adj.

GND

Acceleration

Sensor

Coarse

Gain Adj.

Fine Gain

Adj.

CLK

D/A

Filter

Vref

Buf.

CLK

CLK

Low Pass

A/D

CLK

D/A

Filter

Vref

Buf.

STin

CLK

MXR7900A/C/D FUNCTIONAL BLOCK DIAGRAM

GENERAL DESCRIPTION

The MXR7900A/C/DF is a low cost, dual axis

accelerometer built on a standard, submicron CMOS

process. It measures acceleration with a sensitivity of

900mV/g.

The MXR7900A/C/DF provides a g-proportional

ratiometric analog output above/below the zero-g point at

50% of the supply voltage.

(Ref. other MEMSIC datasheets for absolute analog or

digital outputs).

The typical noise floor is 0.3mg / Hz , allowing signals

below 1mg to be resolved at 1Hz bandwidth. The 3dB roll-

off of the device occurs at 17Hz.

The MXR7900A/C/D is available in a low profile LCC

surface mount package (5mm x 5mm 2mm). It is

hermetically sealed and operational over a -30

°C to +105°C

temperature range.

It can measure both dynamic acceleration (e.g., vibration)

and static acceleration (e.g., gravity).

The design is based on heat convection and requires no

solid proof mass. This eliminates stiction and particle

problems associated with competitive devices and provide

shock survival greater than 50,000 g, leading to

significantly lower failure rates and lower loss due to

handling during assembly and at customer field application.

Due to the standard CMOS structure of the

MXR7900A/C/D, additional circuitry can easily be

incorporated into custom versions for high volume

applications. Contact Memsic’s local office for more

information.

Information furnished by MEMSIC is believed to be accurate and reliable.

However, no responsibility is assumed by MEMSIC for its use, nor for any

infringements of patents or other rights of third parties, which may result from

its use. No license is granted by implication or otherwise under any patent or

patent rights of MEMSIC.

©MEMSIC, Inc.

One Technology Drive, Suite 325, Andover, MA01810, USA

Tel: +1 978 738 0900

Fax: +1 978 738 0196

www.memsic.com