RoboteQ AX2550/2850 user manual Input Circuit Description

R/C Operation

TABLE 15. Connector pin-out in R/C mode

Pin		Input or
Number	Signal	Output	Description
4	R/C Channel 2	Input	Channel 1 input pulse (isolated)
5	Ground	Power	Controller ground (-)
6	R/C -	Power Input	R/C Battery input - (isolated)
7	R/C +	Power Input	R/C Battery input + (isolated)
8	R/C Channel 3	Input	Channel 3 input for On/Off accessories - Not avail-
			able on AX2850.
9	Output C	Output	2A Accessory Output C (same as pin 1)
10	Speed/Pos/T 2	Analog in	Channel 2 speed, position or temp feedback
11	Speed/Pos/T 1	Analog in	Channel 1 speed, position or temp feedback
12	Output D	Output	Low Current Accessory Output D - Not available
			on AX2850.
13	Ground	Power	Controller ground (-)
14	+5V	Power Output	+5V Power Output (100mA max.)
15	Switch Input	Input	Emergency Stop or Invert Switch input

R/C Input Circuit Description

The AX2500/2850 includes an optical isolation barrier on the Channel 1 and Channel 2 R/C radio inputs. Figure 41 shows an electrical representation of the R/C input circuit. The right side is powered from the controller’s batteries. The R/C signals 1 and 2 activate a LED whose light then triggers the photo transistors on the microcontroller side. The left side of the opto isolators include an amplifier and thus need to be powered separately. Notice that channel 3 is optional and not opto-isolated.

Optical isolation is designed to protect the R/C radio from damage that may occur inside the controller, and vice-versa. Additionally, the isolation barrier will help prevent some of the electrical “noise” generated inside the controller by the Microcontroller and the high power switching from reaching and interfering with the radio.

72 AX2500/2850 Motor Controller User’s Manual Version 1.7. February 1, 2005