For more information, please visit the product page. date 11/19/2014 page 1 of 10 SERIES: AMT20 │ DESCRIPTION: MODULAR ABSOLUTE ENCODER FEATURES • • • • • • • • • • patented capacitive ASIC technology low power consumption SPI configurable settings digitally set zero position alignment 12-bit absolute position via SPI (4096 positions) incremental resolutions up to 1024 PPR index pulse compact modular package with locking hub for ease of installation 7 different mounting hole options -40~125°C operating temperature ELECTRICAL parameter conditions/description min typ max power supply VDD 4.5 5 5.5 V current consumption with unloaded output 8 10 mA VDD-0.8 output high level V output low level output current CMOS sink/source per channel rise/fall time units 0.4 V 2 mA 30 ns INCREMENTAL CHARACTERISTICS parameter conditions/description channels quadrature A, B, and Z index min waveform CMOS voltage square wave phase difference A leads B for CCW rotation (viewed from front) quadrature resolutions1 96, 192, 200, 250, 384, 400, 500, 512, 768, 800, 1000, 1024 index one pulse per 360 degree rotation max 90 units degrees PPR accuracy quadrature duty cycle Notes: typ 0.2 degrees 50 % 1. Resolution selected via AMT Demo Board ABSOLUTE POSITION CHARACTERISTICS parameter conditions/description min typ resolution positions max units 12 bits encoder can be zero-set via SPI or AMT Demo Board accuracy 0.2 cui.com degrees For more information, please visit the product page. CUI Inc │ SERIES: AMT20 │ DESCRIPTION: MODULAR ABSOLUTE ENCODER date 11/19/2014 │ page 2 of 10 MECHANICAL parameter conditions/description min motor shaft length typ max 9 weight units mm 15.7 g axial play ±0.3 mm rotational speed 8000 RPM max units 125 °C 85 % ENVIRONMENTAL parameter conditions/description min operating temperature typ -40 humidity non-condensing vibration 10~500 Hz, 5 minute sweep, 2 hours on each XYZ shock 3 pulses, 6 ms, 3 on each XYZ RoHS 2011/65/EU 5 G 200 G max units SERIAL INTERFACE parameter conditions/description protocol Serial Peripheral Interface (SPI) controller min typ SPI driven by onboard Microchip PIC16F6901 data rate 1 1 Note: 1. See Microchip documentation for additional detaisl. WAVEFORMS Figure 1 Quadrature signals with index showing counter-clockwise rotation I X A T B P S S S S The following parameters are defined by the resolution selected for each encoder, where R = resolution. Parameter Description Expression Units T period 360/R mechanical degrees P pulse width T/2 mechanical degrees I index width P/2 mechanical degrees S A/B state width P/2 mechanical degrees cui.com MHz For more information, please visit the product page. CUI Inc │ SERIES: AMT20 │ DESCRIPTION: MODULAR ABSOLUTE ENCODER date 11/19/2014 │ page 3 of 10 PART NUMBER KEY The AMT203 is designed for 12 bit binary (4,096) operation. For customers who may use the optional quadrature output, one of the resolutions below may be selected as the default quadrature output. AMT203 - XXXX - XXXX - X- X Mounting Base: S = Standard W= Wide Base Number Quadrature Resolution (PPR): 0096 0500 0192 0512 0200 0768 0250 0800 0384 1000 0400 1024 Note: Sleeve Bore Diameter: 2000 = 2 mm 3000 = 3 mm 3175 = 3.175 mm (1/8”) 4000 = 4 mm 4760 = 4.76 mm (3/16”) 5000 = 5 mm 6000 = 6 mm 6350 = 6.35 mm (1/4”) 8000 = 8 mm Connector Options: "blank" = standard connector C = locking connector 1. Conformal coating available upon request AMT203-V KIT In order to provide maximum flexibility for our customers, the AMT203 series is provided in kit form standard. This allows the user to implement the encoder into a range of applications using one sku#, reducing engineering and inventory costs. SLEEVES 2mm 3mm 1/8 inch (3.175mm) 4mm 3/16 inch (4.76mm) 5mm 6mm 1/4 inch (6.35mm) 8mm Light Sky Blue Orange Purple Gray Yellow Green Red Snow Blue BASE TOP COVER SHAFT ADAPTER cui.com TOOL A TOOL C For more information, please visit the product page. CUI Inc │ SERIES: AMT20 │ DESCRIPTION: MODULAR ABSOLUTE ENCODER date 11/19/2014 │ page 4 of 10 ENCODER INTERFACE PINOUT CONNECTOR Function # STANDARD CONNECTOR OPTION LOCKING CONNECTOR OPTION AMT203 1 N/A 2 CSB 3 MISO 4 GND 5 SCK 6 +5 V 7 MOSI 8 B 9 N/A 10 A 11 N/A 12 Z 13 N/A 14 N/A B 13 11 9 7 5 3 1 14 12 10 8 6 4 2 B 13 11 9 DETAIL B SCALE 4 : 1 7 5 3 1 14 12 10 8 6 4 2 DETAIL B SCALE 4 : 1 Mating Connector: Samtec ISDF-07-D Mating Connector: Samtec ISDF-07-D-L Demo Board Side Encoder Side 1' 0.25" (304.8) Samtec ISDF-07-D Demo Board Cable (Cable available without Demo Board Connector) cui.com 28 AWG 10 conductor 1.27 mm pitch For more information, please visit the product page. CUI Inc │ SERIES: AMT20 │ DESCRIPTION: MODULAR ABSOLUTE ENCODER date 11/19/2014 │ page 5 of 10 MECHANICAL DRAWING AMT203 units: mm tolerance: ±0.1 10.34 0.407 R15.49 0.610 15.30 0.602 15.33 0.604 37.39 1.472 10.93 0.430 28.58 1.125 AMT203 WIDE BASE units: mm tolerance: ±0.1 10.34 0.407 R15.49 0.610 15.30 0.602 15.33 0.604 37.39 1.472 28.58 1.125 10.93 0.430 52.70 2.075 cui.com For more information, please visit the product page. CUI Inc │ SERIES: AMT20 │ DESCRIPTION: MODULAR ABSOLUTE ENCODER date 11/19/2014 │ page 6 of 10 MECHANICAL DRAWING (CONTINUED) MOUNTING HOLE PATTERNS STANDARD BASE units: mm[inch] tolerance: ±0.1 22.00 0.866 21.55 0.848 20.90 0.823 R1.05 0.041 12.60[0.496] DETAIL A SCALE 4 : 1 2.00 0.079 (4 PLCS) 2.95 0.116 (2 PLCS) 16.00 0.630 0.275 0.011 A (3 PLCS) 1.70 0.067 (2 PLCS) 19.05 0.750 25.40 1.000 WIDE BASE units: mm[inch] tolerance: ±0.1 32.44 1.277 3.00 0.118 (2 PLCS) 2.87 0.113 (2 PLCS) 46.20 1.819 cui.com For more information, please visit the product page. CUI Inc │ SERIES: AMT20 │ DESCRIPTION: MODULAR ABSOLUTE ENCODER date 11/19/2014 │ page 7 of 10 ASSEMBLY PROCEDURE STEP 1 STEP 2 STEP 3 Align Tool C with flange on Base 1. Insert Tool A as a spacer that defines the distance to the mounting surface. 2. Slide appropriate sized Sleeve over shaft all the way down to Tool A. 3. Slide Shaft Adaptor over Sleeve. 4. Use Tool C to press Shaft Adaptor over Sleeve (ensure Shaft Adapter and Tool C spline alignment) until flush with Tool A. STEP 4 1. Remove Tools A and C. 2. Place Base on motor, with Tool C used as a centering tool. STEP 5 STEP 6 1. Snap the Top Cover onto the Base, carefully observing that the teeth of the Shaft Adaptor align with the grooves in the hub. * 1. Fasten the Base on the motor (Tool C may need to be rotated to allow for some mounting configurations). 2. Remove Tool C. 1. Align Tool C with flange on Base. 2. Slide Base and Tool C onto motor, centering onto the Shaft Adapter. * We recommend no more than three cycles of mounting and removal of the AMT top cover base. Multiple cycles of mounting and removing the top cover can cause base fatigue over time and affect encoder performance. cui.com 1. Make sure the snaps are fully engaged by pressing on the Hub with the reverse side of Tool C. 2. When assembly is finished, the Shaft Adaptor, Sleeve and Rotor Hub should all be flush with the Motor Shaft rotating freely. For more information, please visit the product page. CUI Inc │ SERIES: AMT20 │ DESCRIPTION: MODULAR ABSOLUTE ENCODER date 11/19/2014 │ page 8 of 10 APPLICATION NOTES ENCODER OPERATIONAL MODE • Initialization mode: At power up the encoder goes through an initiation and stabilization procedure. This includes microprocessor stabilization and the program for getting the absolute start position. This takes less than 100 milliseconds. • Tracking mode: 1. MCU 12 bit position register is updated from every 48 μs. 2. For accurate position information without the 48 μs incremental outputs A/B can be used for tracking. These outputs are operational up to 8000 RPM without speed error. 3. When using the incremental output there also is a Z index pulse that occurs once per turn. SERIAL PERIPHERAL INTERFACE COMMANDS The Serial Peripheral Interface (SPI) bus is a standard serial interface that operates in full duplex mode. It consists of 4 signals: 1. MOSI: Master Out Slave In 2. MISO: Master In Slave Out 3. SCK: Serial Clock 4. CSB: Chip Select (active low) SPI BUS The SPI bus transfers multiples of 8 bits in a frame. Data is captured on the rising edge of SCK and the output data is changed after the falling edge of SCK. MISO LSB MSB SCK MOSI CSB LSB MSB Terminology MSB = most significant byte LSB = least significant byte msb = most significant bit lsb = least significant bit Setup Serial Peripheral Interface Bus (SPI) on AMT203 Timing Diagram (Figure 1) The data out on MISO is valid once CSB goes low. The MOSI data is valid after the falling edge of SCK. The encoder drives data out on MISO for as long as CSB is low. Normally, CSB goes low, then after 8 clock cycles the command is interpreted. CSB high resets the clock counter, and terminates any command sequence. cui.com For more information, please visit the product page. CUI Inc │ SERIES: AMT20 │ DESCRIPTION: MODULAR ABSOLUTE ENCODER date 11/19/2014 │ page 9 of 10 APPLICATION NOTES (CONTINUED) SPI COMMANDS All commands are 8 bits long. The msb is shifted in first, and is the leftmost bit shown in Figure 1. Encoder Protocol Considerations: The encoder is designed to operate with a high speed SPI link, in full duplex mode. This implies the host can issue commands and read data as quickly as necessary but there has to be an acknowledgement from the slave just before the data is transferred. First the host will issue a command, then the encoder may respond with wait responses (0xA5) until ready. Once ready the encoder will echo the original command received from the master, followed by the requested data. For example, to read the position the master will send the rd_pos command (0x10), it will then send no operation commands (nop_ a5, 0x00) until it receives the original rd_pos command back. Once it receives the rd_pos response from the encoder, it knows that the next two bytes of data will be the MSB and the LSB respectively. To receive those two bytes the master will send two no operation commands. It is recommended that the master leave a 20 μs delay between reads to avoid extending the read time by forcing wait sequences. Command 0x00: nop_a5 (no operation) This no operation command is ignored by the encoder and simply causes the next byte of data to be read. The encoder will respond with 0xA5 if there is no remaining data to be sent. Command 0x10: rd_pos (read position) This command causes a read of the current position. To read 1. 2. 3. 4. position this sequence should be followed: Master sends rd_pos command. Encoder responds with idle character. Continue sending nop_a5 command while encoder response is 0xA5 If response was 0x10 (rd_pos), send nop_a5 and receive MSB position (lower 4 bits of this byte are the upper 4 of the 12-bit position) Send second nop_a5 command and receive LSB position (lower 8 bits of 12-bit positon) Note that it is possible to overlap commands. For instance, instead of issuing nop_a5 for steps 3 and 4, you could begin another read position sequence since the position data is already in the buffer. The read and write FIFOs for the streams are 16 bytes long and it is up to the user to avoid overflow. Command 0x70: set_zero_point (zero set) This command sets the current position to zero and saves this setting in the EEPROM. To set the zero point this sequence should be followed: 1. Send set_zero_point command 2. Send nop_a5 command while response is not 0x80 3. A response of 0x80 means that the zero set was successful and the new position offset is stored in EEPROM. 4. The encoder must be power cycled. If the encoder is not power cycled, the position values will not be calculated off the latest zero position. When the encoder is powered on next the new offset will be used for the position calculation. cui.com For more information, please visit the product page. CUI Inc │ SERIES: AMT20 │ DESCRIPTION: MODULAR ABSOLUTE ENCODER date 11/19/2014 │ page 10 of 10 REVISION HISTORY rev. description date 1.0 initial release 05/01/2010 1.01 updated pin-out 10/01/2010 1.02 updated application note 01/01/2011 1.03 updated SPI commands 09/16/2011 1.04 addition of shock and incremental output current data, correction of vibration data, updated part number key 09/30/2011 1.05 updated Part Number Key 03/09/2012 1.06 updated tools 07/13/2012 1.07 added locking connector drawing 02/12/2013 1.08 updated spec 12/09/2013 updated spec 11/19/2014 1.09 The revision history provided is for informational purposes only and is believed to be accurate. Headquarters 20050 SW 112th Ave. Tualatin, OR 97062 800.275.4899 Fax 503.612.2383 cui.com [email protected] CUI offers a one (1) year limited warranty. Complete warranty information is listed on our website. CUI reserves the right to make changes to the product at any time without notice. Information provided by CUI is believed to be accurate and reliable. However, no responsibility is assumed by CUI for its use, nor for any infringements of patents or other rights of third parties which may result from its use. CUI products are not authorized or warranted for use as critical components in equipment that requires an extremely high level of reliability. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness.