am256l RLS, am256l Datasheet - Page 7

• Manufacturer Part Number: am256l
• Description: Angular Magnetic Encoder Ic
• Manufacturer: RLS

Data sheet
AM256LD01_03
Issue 3, 14
Binary parallel output
Parallel output data is available in 8 bit binary code. To activate parallel output the PS pin must be set low.
Output data can be latched while reading the data.
For CW rotation of the magnet the output position is increasing. It is possible to order an AM256L version
with position increasing for CCW rotation of the magnet (special order).
Incremental output
There are three signals for incremental output: A, B and Ri. Signals A and B are quadrature signals, shifted
by 90°, and signal Ri is a reference mark. Three different numbers of pulses per revolution for quadrature
signals are available: 64 ppr, 32 ppr (selectable with an external pin) and 16 ppr (special order). When 64
ppr is selected, the number of counts per revolution post quadrature evaluation is 256 (64 x 4 = 256). The
reference mark signal is produced once per revolution. The width of the Ri pulse is 1/4 of the quadrature
signal period.
Figure 6 shows the timing diagram of A, B and Ri signals with CW rotation of the magnet at 64 ppr resolution.
B leads A for CW rotation of the magnet. The counting direction can be changed by swapping the A and B
signals.
Edge separation time for 64 ppr:
© 2009 RLS d.o.o.
Parameter
Edge separation time
Edge separation time
th
January 2009
Pos. 255
B
Ri
A
Symbol
t
t
ES
ES
Fig. 6: Timing diagram for incremental output
0
0
Ideal
39
7.8
1
Min.
13
3
2
Unit
µs
µs
A
3
4
Note
At 6,000 rpm
At 30,000 rpm
t
ES
5
6
associate company
7
7