PC BOARD FUNCTIONAL/TEST SPECIFICATION
DESCRIPTION OF ASSEMBLY PCA, SEQ MMIT I/O
PART NUMBER OF ASSEMBLY 47634502, -03, -04
PRODUCT CODE(S) 6241F
RELEASE NUMBER 66764/1018294
RELEASE DATE 4/15/10 (Updated 2/24/10)
- product description overview
- introduction
The Sequencer MMIT I/O Assy replaces the sequencer I/O box, the Optical Refire controllers, and the 20 AC Out PCBs with a single I/O card that interfaces to the Mini-MIT bus that has been used on the SMT Platform since its inception. The card has 20 DC outputs capable of driving up to 1 amp each at 12 VDC. The card has 40 inputs that are nominally dedicated for low parts and parts missing for the dispensing heads. In addition, the card has a diagnostic port which is not connected to any outputs and 8 general purpose inputs and outputs for other features such as start and stop switches.
- history
This card is a new design, but based on experience with Mini-MIT on the platform. The functions of this I/O card are the same as those of the modules it replaces (refire controller, 20 AC Output).
- physical description
The card is the same size as the 20 AC Output (5”x15”). The construction is a multi-layer surface mount assembly. To streamline manufacture, as many of the components as possible are surface mount.
- Compatibility
This card is designed to completely replace the previous control scheme. The only compatibility to existing equipment is for the dispensing heads and the jumper wire feeder. This card will support the new (stepper controlled) or old feeder. The cabling to the jumper wire feeder, however, is different. This card will not support the older AC valves or the old Refire Det PCBs. DC valves are required and the new Refire Det PCA is needed.
- operating features
The Seq MMIT I/O PCA an I/O card optimized for use on the IM sequencers. It has separate connectors for Mini-MIT in and out, and has separate connectors for each of the functions supported. In this way, the cabling can be modular, avoiding massive cable harnesses. All signals are routed through the gate array, which is programmable. Thus, the card’s function can be tailored to suit many diverse needs. The card is designed for low power consumption which reduces the cost of cables and eliminates any thermal problems. All signals going off board are conditioned to protect the board from damage from accidental wiring errors.
- operating specifications
- electrical power requirements
ï +12 VDC @ 4 A max.
ï +5 VDC @ 2 A max.
ï 24 VAC @ 2.5 A max.
Over current protection for the main +12 VDC and +5 VDC are provided by the power supply. The power supply should not be replaced without due consideration to the over current protection.
- Thermal considerations
There are no reasons for concern for any expected thermal conditions in the environment that it will be used in.
- inputs
There are 48 inputs that are optically isolated and filtered. These are used for (20) part missing, (20) low parts and (8) general purpose inputs.
- 5 V OPTO: Inputs are optically isolated with noise rejection. The input signals are referenced to the local +5 VDC supply. The inputs must be pulled below 2.7 VDC (2.3 VDC across the input) to activate the input. To guarantee the inactive state, the input must be above 3.6 VDC. There is a 0.01?F filtering capacitor across the opto-coupler to filter out high frequency noise. In addition, there is debouncing in the gate array to weed out signals shorter than approximately 50 ?s.
- 12 V OPTO: Inputs are optically isolated with noise rejection. The input signals are referenced to the local +5 VDC supply. The inputs must be pulled below 9.2 VDC (2.8 VDC across the input) to activate the input. To guarantee the inactive state, the input must be above 10.3 VDC. There is a 0.01?F filtering capacitor across the opto-coupler to filter out high frequency noise. In addition, there is debouncing in the gate array to weed out signals shorter than approximately 50 ?s.
- 24 VAC OPTO: There is one input referenced to 24 VAC for the TEST input from the jumper wire feeder. This input is diode blocked to provide a pulsing signal. There is one pulse per AC cycle. The input pulses are stretched in the gate array to approximately 27 ms. The input line must be pulled below 12 VACrms to guarantee an active signal and must be above 18 VACrms to guarantee an inactive state.
- TTL INPUT: This is used only for a jumper in the plug that connects to this board to indicate that it is plugged in. This signal does not go off board any distance.
- outputs
There are (20) 12 VDC sourcing outputs for valve solenoids. Each is capable of driving up to 1 A. There are 8 general purpose outputs that are also 12 VDC sourcing. In addition, 5 of these general purpose outputs also have AC relays on them capable of sourcing 24 VAC at up to 1 A.
- O.D. SOURCING: Open drain MOSFET output referenced to the local +12 VDC supply. They are capable of sourcing 1 A each. The total limit of the 12 V supply is 4 A.
- 24 VAC SOURCING: Triac output supplies 24 VAC at a maximum of 1 A.
- O.C. Sinking: Open collector TTL output (7407) referenced to the 5 VDC return (GND). These outputs are used for data links to adjacent boards.
- connector pin out
Power Input: 15 pin AMP Mate-n-lok connector that supplies +12 VDC, return, +5 VDC, return, 24 VAC, switched 24 VAC, and return, and an external power source.
Jumper Wire Feeder: 6 pin AMP Mate-n-lok connector that supplies 24 VAC, return, the DC output for head 3 and the Out of Wire input for head 3. The output and input are in parallel with the output and input for the dispensing head itself. In addition, there is a Test input from the jumper wire feeder that will manually feed a wire and fire the dispensing head.
Valve Drivers: (4) 10 pin Mod-U connectors supplying 5 sourcing signal lines and 5 return lines. These outputs are open drain P-channel MOSFETs.
