7
Encoding Characteristics
Encoding characteristics are applicable per the Recommended Operating Conditions, unless otherwise specied. Values
are for the worst case error over the full rotation.
Description Sym. Min. Typ.* Max. Units
Two Channel Pulse Width Error
Logic State Width Error
Phase Error
Position Error
Cycle Error
∆P
∆S
∆Φ
∆Θ
∆C
7
5
2
10
3
45
45
20
40
5.5
°e
°e
°e
min. of arc
°e
Three Channel Pulse Width Error
Logic State Width Error
Phase Error
Position Error
Cycle Error
Index Pulse Width
∆P
∆S
∆Φ
∆Θ
∆C
P
O
55
5
5
2
10
3
90
45
35
15
40
5.5
125
°e
°e
°e
min. of arc
°e
°e
CH.I rise after CH.A or
CH. B fall
-40° C to +100° C t
1
-300 100 250 ns
CH.I fall after CH.A or
CH. B rise
-40° C to +100° C t
2
70 150 1000 ns
Electrical Interface
To ensure reliable encoding performance, the three
channel single ended encoders require 2.7 kΩ (±10%)
pull-up resistors on output pins 2, 3 and 5 (Channels A, B
and I) as shown in Figure 1. These pull-up resistors should
be located as close to the encoder as possible (within 4
feet). Each of the outputs can drive a single TTL load in this
conguration. The two channel version does not normally
require pull-up resistors. However, 3.2 kΩ pull-up resistor
on output pins 3 and 5 (Channel A and B) are recommended
to improve rise times, especially when operating above
100 KHz frequencies.
For the line driver option, dierential loading of 100 Ω and
40 pf (RS422 conguration), yields rise and fall times of
120 ns typical, with approximately 60 ns of skew. Driving
moderate to long lengths of cable un-terminated reduces
power consumption and can reduce skew to < 10 ns.
Figure 1. Pull-up resistors on 3 Channel encoder output
GND
CH. B
CH. I
CH. A
V
CC
R
+5V
TO OUTPUT LOGIC
(ONE TTL PER OUTPUT)
5
1
R = 2.7 kΩ
RR
