80 Rockwell Automation Publication 2094-UM001J-EN-P - March 2017
Chapter 4 Connector Data and Feature Descriptions
Table 53 - AM, BM, and IM Input Specifications for TTL Encoders
Table 54 - AM, BM, and IM Input Specifications for Sine/Cosine Encoders
Table 55 - Specifications for Heidenhain EnDat Encoders
Feedback Power Supply Specifications
The IAM and AM power circuit board generates +5V and +9V DC for motor
and auxiliary feedback power. Short circuit protection and separate common
mode filtering for each channel is included.
Parameter Description Min Max
AM, BM, and IM
On-state input voltage
Input voltage difference between the plus (+) input and the
minus (-) input that is detected as an on-state.
+1.0V +7.0V
AM, BM, and IM
Off-state input voltage
Input voltage difference between the plus (+) input and the
minus (-) input that is detected as an off-state.
-1.0V -7.0V
Common mode
input voltage
Potential difference between any encoder signal and logic
ground.
-7.0V +12.0V
DC current draw Current draw into the + or - input. -30 mA 30 mA
AM, BM input
signal frequency
Frequency of the AM or BM signal inputs. The count frequency is
4 times this frequency, because the circuitry counts all four
transitions.
–500 kHz
IM pulse width
Pulse width of the index input signal. Because the index is active
for a percentage of a revolution, the speed determines the pulse
width.
125 nS –
AM, BM phase error
250 KHz line frequency
Amount that the phase relationship between the AM and BM
inputs can deviate from the nominal 90°.
-22.5° +22.5°
AM, BM phase error
100 KHz line frequency
Amount that the phase relationship between the AM and BM
inputs can deviate from the nominal 90°.
-45° +45°
Parameter Description Min Max
Sine/cosine
input signal
frequency
Frequency of the Sine or Cosine signal inputs. – 250 kHz
Sine/cosine
input voltage
Peak-to-peak input voltages of the Sine or Cosine inputs. 0.8V (p-p) 1.2V (p-p)
Command Set
Order
Designation
Description
EnDat 2.2 EnDat 01 1V p-p Sin/Cos, <2 MHz clock frequency
Supply Reference
Voltage Current mA
Min Nominal Max Min Max
+5V DC EPWR_5V 4.9 5.25 5.4 0 400
+9V DC EPWR_9V 8.3 9.1 9.9 0 275