DA6512.000

11 July, 2012

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1 (26)

MAS6512

Capacitive Sensor Signal Interface IC

•

Single or Dual Capacitance Sensors

•

Low Voltage Operation

•

Low Power Consumption

•

On Chip Temperature Sensor

•

Internal Clock Oscillator

•

16-Bit Ratiometric ∆

∆

∆

∆Σ

Σ

Σ

Σ CDC

•

EEPROM Calibration Memory

•

Serial Interface

DESCRIPTION

MAS6512 capacitive sensor signal Interface IC can

interface both single and dual capacitance sensors.

It

uses

a

16-bit

Capacitance-to-Digital

Converter (CDC), which employs a delta-sigma

( Σ) conversion technique. The output data from

the

Σ-modulator is processed by an on-chip

decimator

filter,

producing

a

high

resolution

conversion result. The converter is run by an

internal

clock

oscillator

making

an

external

converter clock unnecessary.

The converter input range is programmable

to meet various sensor offset and changing

capacitance values. Maximum sensor capacitance

is 40pF but higher maximum value can be reached

by using slower conversion speed or scaling the

signal by using an external series capacitor.

The measurement resolution depends on

the programmed capacitance range and over

sampling ratio (OSR) selections.

MAS6512

supports

two

capacitance

measurement

modes.

The

output

can

be

The IC is designed especially to meet the

requirement for low power consumption, thus

making it an ideal choice for battery powered

systems. Current consumption values of 28 µA with

high resolution or 1.9 µA with low resolution, at a

conversion rate of one conversion per second, can

be achieved.

In addition to measuring capacitance the

device has an internal temperature sensor for

temperature

measurement

and

temperature

compensation purposes. The 256-bit EEPROM

memory stores trimming and calibration coefficients

on chip.

A serial interface, compatible with a bi-

directional 2-wire I

used for conversion setup, starting a conversion

and reading the conversion result.

FEATURES

APPLICATIONS

•

Single and Differential Capacitive Sensors

•

Sensor Offset and Gain Adjustment

•

Changing Capacitance Range 2pF…30pF

•

Internal Offset Capacitance Matrix 0pF…22pF

•

External Capacitance up to 40pF (or higher

using external clock)

•

Resolution 14 bit (OSR=4096, ∆C=20pF)

•

Internal Clock Oscillator

•

On Chip Temperature Sensor -40°C...+85°C

•

Low Voltage Operation 1.8 V…3.6 V

•

Low Supply Current: 1.9 µA...28 µA

•

Conversion Time 5.8ms...82.6ms (12Hz...173Hz)

•

16-bit Ratiometric ∆Σ CDC

•

Internal 256-bit EEPROM Calibration Memory

•

I

•

QFN-16 Package

•

Capacitive Pressure Sensors

•

Humidity Sensors

•

Medical Devices

•

Flow Meters

•

Sport Watches

•

Altimeter and Barometer Systems

•

Mobile and Battery Powered Systems

•

Low Frequency Measurement applications

•

Current/Power Consumption Critical Systems

•

Industrial and Process Control applications in

noisy environments

This is preliminary information on a new

product under development. Micro Analog

Systems Oy reserves the right to make any

changes without notice.