Elmo Computer Hardware 1.1 User Manual
3.5
Integrating the Guitar on a PCB
The Guitar is designed to be mounted on a PCB, either by soldering its pins directly to the
PCB or by using suitable socket connectors. In both cases the following rules apply:
PCB or by using suitable socket connectors. In both cases the following rules apply:
3.5.1 Traces
1. The
size of the traces on the PCB (thickness and width) is determined by the current
carrying capacity required by the application.
The rated continuous current limit (Ic)of the Guitar is the current used for sizing
the motor traces (M1, M2, M3 and PE) and power traces (VP+, PR and PE).
For control, feedbacks and Inputs/ outputs conductors the actual current is very
small but “generous” thickness and width of the conductors will contribute to a
better performance and lower interferences.
2. The
traces should be as short as possible to minimize EMI and to minimize the heat
generated by the conductors.
3. The
spacing between the high voltage conductors (VP+, PR, M1, M2, M3, VL) must be
at least:
Surface layer:
1.5 mm
Internal layer:
0.5 mm
Complying with the rules above will help satisfy UL safety standards, MIL-STD-275 and the
IPC-D-275 standard for non-coated conductors, operating at voltages lower than 200 VDC
and at “unlimited altitudes” (above 10,000 meters – 30,000 feet).
IPC-D-275 standard for non-coated conductors, operating at voltages lower than 200 VDC
and at “unlimited altitudes” (above 10,000 meters – 30,000 feet).
3.5.2 Grounds and Returns
The “Returns” of the Guitar are structured internally in a star configuration. The returns in
each functional block are listed below:
each functional block are listed below:
Functional Block
Return Pin
Power
PR (Power Return)
Internal Switch Mode P.S.
PR (Power Return)
RS232 Communications
RS232_COMRET (J1/3)
CAN Communications
CAN_COMRET (J1/30)
Control section
COMRET (J1/28)
Main Feedback
SUPRET (J2/2)
Aux. Feedback
SUPRET (J1/6)
Analog input
ANLRET (J2/2)
The returns above are all shorted within the Guitar in a topology that results in optimum
performance.
performance.
1. When wiring the traces of the above functions, on the Integration Board, the Returns of
each function must be wired separately to its designated terminal on the Guitar. DO
NOT USE A COMMON GROUND PLANE. Shorting the commons on the Integration
Board may cause performance degradation (ground loops, etc).
NOT USE A COMMON GROUND PLANE. Shorting the commons on the Integration
Board may cause performance degradation (ground loops, etc).
Guitar Installation Guide
Installation
MAN-GUIIG (Ver. 1.1)
3-6