Editing Argon user guide/J5 connector electrical interfacing

This article explains the internal circuity behind J5 connector of [[Argon (servo drive)|Argon servo drive]].
{{info|Exceeding ratings may affect drive operation and cause instability or even damage the drive.}}

==Pin functions==
See main article [[Argon wiring]]
==Pin electrical categories==
===Supply===
Supply pins output a regulated 5V voltage to external circuits. GND pin is tied to J3 connector V- terminal.

;Electrical properties
*Output voltage 4.9-5.2 V
*Maximum load 500 mA 
*Maximum injected current -10 mA
{{Caution|Never connect multiple supply outputs parallel. Supply output may be connected only current consuming circuity to prevent current injection to the supply port.}}

===High speed digital input===
[[File:hsin.png|thumb|Simplified HSIN circuity inside the drive. Left side end represents J5 pins and right side continues to drive internal circuity.]]
HSIN is differential digital input capable of receiving digital signals up to 4 MHz. 

;Electrical properties
*Maximum voltage to HSINx+/- pins referenced to GND: -0.5 to 6V. Nominal 3.3 or 5.0V.
*Maximum injected current +/- 10 mA
*When negative input (HSINx-) is left floating, it floats around 2.5V
*Input state is logic 1 when voltage on positive pin is greater than voltage on negative pin, otherwise it's logic 0

;Wiring when driving using differential source
*Positive outputs of source to HSINx+
*Negative outputs of source to HSINx-
*GND must be connected to source ground

;Wiring when driving using single ended source (TTL, CMOS or open collector)
*Outputs of source to HSINx+
*Leave HSINx- floating
*GND must be connected to source ground

===Analog input===
[[File:anain.png|thumb|Simplified analog input circuity inside the drive. Left side end represents J5 pins and right side continues to drive internal circuits.]]
Analog input accepts ±10V from and may be used as [[Reference signal|reference signal]].
;Electrical properties
*Input impedance ~10 kΩ
*Maximum ANAINx+/- pin voltage vs GND ±20V
*Maximum injected current ±10 mA
*Sampling resolution 12 bits
;Wiring to differential signal source
*Connect positive output to ANAINx+
*Connect negative (inverted) output to ANAINx-
*Connect source ground to GND
;Wiring to single ended signal source
*Connect output to ANAINx+
*Connect source ground to ANAINx-
*Connect source ground to GND

===Digital output===
[[File:gpo.png|thumb|Simplified digital output circuity inside the drive. Left side end represents J5 pins and right side continues to drive internal circuits.]]
Digital output is an optoisolated transistor output to drive various types of inputs of target devices (logic gates, relays, lights etc)
;Electrical properties
*Load voltage range 3-24V
*Maximum allowed load 50 mA
*Logic 1 state equals conducting state of optocoupler transistor (current flows from GPO+ to GPO- pins), logic 0 stops current flow between GPO+ to GPO- pins.
*+ to - pin voltage drop at 50 mA less than 2 VDC
{{caution|Digital output isolation is only functional and does not provide safety insulation. Connect only to [http://en.wikipedia.org/wiki/Extra-low_voltage ELV circuits].}}
;Wiring to logic gate input (CMOS or TTL)
*Connect GPO+ pin to target VCC (typ 5V)
*Connect GPO- pin to target input pin (so input pin is pulled to 5V when output state is logic 1)
===Digital input===
[[File:gpi.png|thumb|Simplified digital input circuity inside the drive. Left side end represents J5 pins and right side continues to drive internal circuits. D27 protects optocoupler from reverse polarity and ESD.]]
Digital inputs are optoisolated (floating potential) inputs for general purpose control signals.
;Electrical properties
*Signal voltage range 3-24V
*Logic 0 when difference between +/- inputs less than 1.5V, logic 0 when more than 2.9V
*Current needed to drive logic 1 is 0.8-9 mA depending on input voltage
*Maximum voltage difference between GPIx+/- inputs 27 VDC
*Maximum voltage difference between GPIx+/- inputs vs GND 120 VDC
{{caution|Digital input isolation is only functional and does not provide safety insulation. Connect only to [http://en.wikipedia.org/wiki/Extra-low_voltage ELV circuits].}}
;Connection to electromechanical switch or relay
[[File:gpiswitch.png|thumb|Connection from electromechanical switch or relay to isolated digital input. PSU may be external power supply or 5V supply from J5 connector.]]
*See schematics image in right side
;Connection to CMOS source
*Connect source output to GPIx+ input 
*Connect source ground to GPIx- input
;Connection to open collector or TTL source
*Connect source output to GPIx- input 
*Connect source VCC (typ 5V) to GPOx+ input