Product category:
Analogue and Mixed Signal ICs
News Release from: iC-Haus | Subject: iC-MQ
Edited by the Electronicstalk Editorial
Team on 19 November 2007
Conditioner accounts for position sensor
errors
The iC-MQ ensures that the parameters set initially for the offset, amplitude and phase correction are kept valid.
New from iC-Haus, the iC-MQ is a universal signal conditioning IC that is suitable for optical and magnetic linear and angle sensors Inbuilt diagnostic features detect operational errors, such as signal loss or clipping, exceeding a preset operating temperature range or speed or a line count error of the scale or disc pattern
This article was originally published on Electronicstalk on 11 Aug 2008 at 8.00am (UK)
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Such errors can be signalled externally and/or transferred to a nonvolatile diagnostic memory.
The iC-MQ provides up to 400 angle steps for sine interpolation; to improve angle accuracy, this basic function is supplemented by a finely adjustable signal conditioning circuitry, a signal path multiplexer (which keeps pin functions variable) and fault-tolerant RS422 line drivers.
Device installation with incorrectly connected wires is tolerated by iC-MQ - even when the supply voltage is reversed.
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The iC-MQ itself ensures that the parameters set initially for the offset, amplitude and phase correction are kept valid.
To this end sensor energising can be tracked via a 50mA high-side source output; the LED current of an optical encoder or the supply of magnetic XMR bridge sensors can be regulated.
Temperature and aging effects or varying operating distances are automatically compensated.
All the chip's major functions are monitored and can be configured for alarm indication, allowing typical sensor errors, such as signal loss due to wire breakage, short circuiting, dirt or aging, for instance, to be recognised.
The mode of error handling can be extensively configured using event masks; an alarm can be displayed at the error output, set the output drivers to tri-state and be transmitted to the error memory for later diagnosis.
The encoder signals are supplemented by a generated index signal whose position, width and logic can be set as required.
At the same time a patented signal conditioning unit provides glitch-free quadrature signals with hysteresis which always maintain a preselectable minimum transition distance.
This enables counting errors to be avoided and enhances the circuit's EMI tolerance with sensor applications.
The iC-MQ is available in a 20-pin TSSOP, which takes up just 6.4 x 6.4mm board space.
It is configured using the integrated I2C multimaster interface, either by a microcontroller or a serial EEPROM.
Via an integrated supply switch the iC-MQ also protects the peripheral electronics against reversed supply voltage.
With a single supply of +5V the device functions within an industrial operating temperature range of -25 to +100C.
An extended temperature range can also be provided, as the convertor chip has been designed to cope with operating temperatures of -40 to +125C.
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