CMA3000-A01-1 参数 Datasheet PDF下载

CMA3000-A0X Series

1

1.1

General Description

Introduction

CMA3000-A0X is a three axis accelerometer family targeted for high volume products requiring

small size, low price and low power consumption. It consists of a 3D-MEMS sensing element and a

signal conditioning ASIC in a wafer level package.

Both block diagram of CMA3000-A0X is shown in Figure 1 below.

X-out

C/V

Analog

calibration

&

low-pass

filtering

Y-out

Z-out

Oscillator

&

clock

Reference

Non-

Volatile

Memory

Control

Range

PD

Figure 1. CMA3000-A0X block diagram with analog interface

This document, no. 82821000, describes the product specification (e.g. operation modes, electrical

properties and application information) for the CMA3000-A0X family. The specification for an

individual sensor is available in the corresponding data sheet.

1.2

1.2.1

Functional Description

Sensing element

The sensing element is manufactured using the proprietary bulk 3D-MEMS process, which enables

robust, stable and low noise & power capacitive sensors.

The sensing element consists of three acceleration sensitive masses. Acceleration will cause a

capacitance change that will be then converted into a voltage change in the signal conditioning

ASIC.

1.2.2

Interface IC

CMA3000 includes an internal oscillator, reference and non-volatile memory that enable the

sensor's autonomous operation within a system.

The sensing element is interfaced via a capacitance-to-voltage (CV) converter. Following

calibration in the analog domain, the signal is filtered and buffered.

In active mode analog voltages representing the measured acceleration are available X-, Y-, Z-out

pins. Power Down and measurement range can be selected using external Range ('0'=8g, '1'=2g)

and PD ( '0' =Active, '1'= Power Down ) pins.

1.2.3

Factory calibration

Sensors are factory calibrated. Trimmed parameters are gain, offset, internal current reference and

the frequency of the internal oscillator. Calibration parameters will be read automatically from the

internal non-volatile memory during sensor startup.

VTI Technologies Oy

www.vti.fi

PRELIMINARY - Subject to changes

Doc.Nr. 8282100.05

4/ 17

Rev.05