date
11/2010
page
1 of 7
PART NUMBER: AMT303
The AMT 303 is a commutation
encoder with additional incremental
channels A, B, and Z. The encoder
output utilizes standard U,V,W
commutation signals with additional
quadrature A,B and Index signals
provided for speed control or
positioning operations. A SPI serial
bus allows for commutation settings
to be easily adjusted via a demo
board, or preconfigured and stored
for large production assembly for
various motor configurations.
DESCRIPTION:
FEATURES
-
-
-
-
-
-
-
COMMUTATION ENCODER
U,V,W Commutation lines
Small Size 37mm
Line count up to 1024
Optional Line Driver output
Single pulse index
Capacitive ASIC technology
Modular locking hub design for
ease of installation
- 2,4,6,8,10,12, or 20 pole motors
- SPI adjustable settings
- ‘One Touch’ commutation signal
alignment
ELECTRICAL SPECIFICATIONS
parameter
power supply
current consumption
commutation output signals
commutation pole
incremental output signals
incremental output waveform
incremental output resolutions
Index
incremental output current
U, V, W phase
2, 4, 6, 8, 10, 12, 20 (software programmable)
A, B, Z phase (A, B, Z available on AMT303LD)
square wave
96, 192, 200, 250, 400, 500, 512, 1024
one pulse per 360 deg
output voltage - sourcing to +5 V @ -32 mA
output voltage - sinking to ground @ -32 mA
3.8
0.55
V
V
96
512
1,024
ppr
conditions/description
min
4.5
nom
5
8
max
5.5
10
units
V
mA
MECHANICAL SPECIFICATIONS
parameter
output range
mounting hole options
A) 2 each M1.6 on 16 mm (0.63”) bolt circle
B) 2 each #4 on 19.05 mm (0.75”) bolt circle
C) 2 each M1.6 or M2 on 20 mm (0.787”) bolt circle
D) 3 each M1.6 or M2 on 20.9 mm (0.823”) bolt
circle with washers in option B holes
E) 3 each M1.6 or M2 on 22 mm (0.866”) bolt circle
F) 4 each M1.6 or M2 on 25.4 mm (1”) bolt circle
conditions/description
min
nom
max
360
units
deg
ENVIRONMENTAL SPECIFICATIONS
parameter
operating temperature
humidity
vibration
1.5mm, 3 directions, 2 hours
10
conditions/description
min
-40
nom
max
125
85
55
units
°C
%RH
Hz
20050 SW 112
th
Ave. Tualatin, Oregon 97062
phone 503.612.2300
fax 503.612.2380 www.cui.com
date
11/2010
page
5 of 7
PART NUMBER: AMT303
DESCRIPTION:
COMMUTATION ENCODER
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 combining Coarse
and Fine channel of the encoder for getting the absolute start position. This takes
less than 0.1 seconds.
•
Tracking mode:
– MCU 12 bit position register is updated from Fine Asic every 48
μs.
– The commutation program in the MCU has a compensation for the average delay caused by the
update rate, leaving a remaining jitter of less than 24
μs
RMS.
•The communication jitter expressed in electrical degrees will be proportional speed and
does not reach 6 deg RMS until the speed reaches the following values:
Pole Count
Speed Limit RPM
4
17,361
6
11,574
8
8,681
10
6,944
12
5,787
20
3,472
Serial Peripheral Interface Commands
The SPI or Serial Peripheral Interface Bus is a standard interface promoted by Motorola and Microchip among
others. It consists of 4 signals:
MOSI: Master Out Slave In
MISO: Master In Slave Out
SCK: Serial Clock
CSB: Chip Select Bar (active low)
SPI BUS
The SPI bus runs full duplex and transfers multiples of 8 bits in a frame. The SPI type is the most common
(CPOL=0, CPHA=0), also known as Microwire. Data is captured on the rising edge of SCK and the output data is
changed after the falling edge of SCK.
Figure 7: SPI BUS Timing Diagram
MISO
SCK
lsb
msb
Terminology
MOSI
msb
Setup
lsb
MSB = most significant byte
LSB = least significant byte
msb = most significant bit
lsb = least significant bit
CSB
Serial Peripheral Interface Bus (SPI) on AMT303
20050 SW 112
th
Ave. Tualatin, Oregon 97062
phone 503.612.2300
fax 503.612.2380 www.cui.com
TI Technology Forum
京公网安备 11010802033920号
EEWORLD
