iC-MU Magnetic off-axis absolute position encoder iC-MU is an all-in-one, off-axis, magnetic position sensor featuring integrated Hall sensors with automatic signal conditioning and processing. The nonius scanning of two magnetic tracks (a master and a nonius track) is evaluated by two real-time-tracking sine-to-digital converters. Following power up and nonius computation, iC-MU provides incremental encoder quadrature signals with an index of any count up to 65,536 CPR and an output at an adjustable minimum edge distance. It also gives the absolute singleturn position with up to 18 bits per revolution through various serial interfaces (SSI, BiSS, SPI). Commutation signals for brushless motors with up to 16 pole pairs are derived from the absolute position and supplied through a 3-pin interface. The commutation starting angle can be preset. External counters can be supplied with pulse signals for cw and ccw or for step and direction. iC-MU captures full revolutions with its embedded 24-bit period counter and can thus supplement the position data output for data lengths of up to 38 bits. Optionally, using the multiturn interface the counter can be loaded following a reset by an external 12-bit multiturn sensor, for instance. The data is read and synchronized with the internal position data, and is cyclically checked during operation. A preset function permits the adjustment of the absolute position after encoder installation. VPA Features • • • • • • • • • • • • • • • • • Two-track Hall sensor scanning for 1.28 mm pole width Precise signal conditioning for offset, amplitude, and phase Synchronous 12-bit sine-to-digital conversion per track Nonius computation of absolute position with up to 18 bits 16, 32, or 64 pole pairs per measurement distance Linear speed to 16 m/s, rotational speed to 24,000 RPM Position data output via fast serial interfaces (SPI, SSI, BiSS C) Incremental encoder quadrature outputs (A, B, Z) FlexCount® resolution for 1 to 65536 CPR Motor commutation signals for up to 16 pole pairs (U, V, W) Counter signals and sin/cos signals optionally available Serial 12-bit multiturn interface Position preset function Device setup via SPI or I²C from external EEPROM Operational temperature range of –40°C to 95°C Small 16-pin DFN Package of 5 mm x 5 mm Magnetic targets available Applications • • • Non-contact position measurement Linear scales and rotary encoders Motion control, motor feedback VPD MASTER TRACK PA0 PB0 B PA1 PB1 12 BIT NONIUS TRACK PA2 PB2 B PA3 PB3 12 BIT SER INTERFACE HALL SENSORS + PGA SINUS/DIGITAL CONFIGURATION ANA/DIG OUTPUT iC-MU 128 Byte RAM AMPLITUDE CONTROL SCL CLOCK SDA I2C EEPROM INTERFACE MTC SYNCHRONISATION INTERFACE HANDLER BIAS ERROR MANAGEMENT REFERENCE ENCODER PROCESSOR VNA MTD MULTITURN VND Am Kuemmerling 18 • D -55294 Bodenheim, Germany Tel. +49 61 35 / 92 92-30 0 • Fax +49 61 35 / 92 92-19 2 • http://www.ichaus.com iC-MU Magnetic off-axis absolute position encoder Besides 2-track nonius computation iC-MU is capable of extending the rotary or linear absolute position using 3-track nonius computation. A second iC-MU can be connected up and evaluated using the multiturn interface. In doing so, the length of the absolute position measurement can be extended. Besides its automatic signal conditioning functions iC-MU features manual compensation of the sine/cosine signal offsets and phase errors for both channels, allowing it to cope with magnet errors and encoder assembly inaccuracies. Upon cycling power iC-MU loads its CRC-protected setup from the external EEPROM connected up to the I²C interface. Alternatively, using the SPI interface the device can be configured and operated by an external microcontroller. Key Specifications General Supply Voltage +4.5 V to +5.5 V Supply Current 50 mA max. Max. Operating Frequency 6.4 kHz Max. Operating Speed linear speed to 16 m/s, rotational speed to 24,000 RPM @ 16 pole pairs, to 12,000 RPM @ 32 pole pairs, to 6,000 RPM @ 64 pole pairs Magnetic Field Strength 15 to 100 kA/m ESD Susceptibility 2 kV (HBM 100 pF, 1.5 kΩ) Operational Temperature -40°C to +95°C Package (RoHS compliant) 16-pin DFN (5 mm x 5 mm) Sine-to-Digital Conversion Pin Functions Conversion Resolution up to 12 bits per signal period (14 bits filtered) No. Name Function Conversion Accuracy 2 LSB @ 12 bit 1 SCL Analog Cutoff Frequency 20 kHz (-3 dB) 2 SDA EEPROM I²C Interface, clock line EEPROM I²C Interface, data line 3 VPA +4.5 V to +5.5 V Analog Supply Voltage 4 VNA Analog Ground Nonius of 16/15 * 18 bits (filtered), 5 arcsec / 0.156 µm 5 PB0 Port B, Pin 0: Digital I/O, analog output configurable Nonius of 32/31 * 19 bits (filtered), 2.5 arcsec / 0.156 µm Nonius of 64/63 * 20 bits (filtered), 1.25 arcsec / 0.156 µm 6 PB1 Port B, Pin 1: Digital I/O, analog output configurable * No. of signal periods (18 bits max. for A/B outputs) 7 PB2 Port B, Pin 2: Digital I/O, analog output configurable Absolute Linear Measurement Distance Nonius of 32/31 8 PB3 Port B, Pin 3: Digital I/O, analog output configurable up to 81.9 mm (signal phase tolerance +/- 40 µm max.) Nonius of 64/63 9 PA3 Port A, Pin 3: Digital I/O, configurable up to 163.8 mm (signal phase tolerance +/- 20 µm max.) Nonius of 1024/1023/992 10 PA2 Port A, Pin 2: Digital I/O, configurable up to 2.62 m (two iC-MU cascaded and operated at 32/31) 11 PA1 Port A, Pin 1: Digital I/O, configurable Output Ports Characteristics CMOS/TTL compatible, ±4 mA @ 5 V 12 PA0 Port A, Pin 0: Digital I/O, configurable PAx Port Modes SPI, SSI, BiSS C, A/B/Z PBx Port Modes A/B/Z, U/V/W, STEP/DIR, CW/CCW, Sin/Cos 250 mVpk Incremental Signals A/B to 5 MHz, Z index (adjustable gating) FlexCount® resolution for 1 to 65536 CPR Commutation Signals U/V/W for 1 to 16 pole pairs, phase shift 60° or 120° 13 VND Digital ground 14 VPD +4.5 V to +5.5 V Digital Supply Voltage 15 MTD Multiturn Interface, data line 16 MTC Multiturn Interface, clock line TP Thermal Pad Pin Configuration DFN16 5x5 mm² 1 2 3 4 5 6 7 8 MU ... yyww... 16 15 14 13 12 11 10 9 Position Resolution Data Interfaces SPI 4-wire, 10 MHz, for position data and config. BiSS C up to 38 data bits, error bits, CRC protection, bidirectional, 10 MHz SSI up to 38 bits, error bits, unidirectional, 4 MHz Multiturn 12 bit SSI, 200 kHz Magnetic Targets (pole wheels) MU1S 19-16 16/15 pole pairs, OD Ø 19 mm, bore hole 10M6 MU2S 30-32 32/31 pole pairs, OD Ø 30 mm, bore hole 10M6 MU3S 56-64 64/63 pole pairs, OD Ø 56 mm, bore hole 10M6 This preliminary information is not tantamount to a guarantee of device characteristics. All rights to technical changes reserved Am Kuemmerling 18 • D -55294 Bodenheim, Germany Tel. +49 61 35 / 92 92-30 0 • Fax +49 61 35 / 92 92-19 2 • http://www.ichaus.com Rev. 1.0