Technosoft iPOS360x MX, Техническое описание, Страница: 37 / 116


Technosoft 2014 25 iPOS360x MX Technical Reference

In multi-axis applications (multiple iPOS360x drives on the same motherboard), it is
preferable to have a separate decoupling capa
citor for each drive’s V
MOT
. For V
LOG
it is
acceptable to share one decoupling capacitor for two drives.

For stringent EMI requirements, it may be necessary to add common-mode filtering on the
motor and/or logic supply inputs. Be sure to use 3-phase EMC filters, not 2-phase filters, in
order to fulfill the basic requirement of zero common-mode current through the filter. This
is necessary because the ground negative return is shared between V
MOT
and V
LOG
.

Motor outputs shall be routed with parallel traces, and minimizing the loop area between
these tracks. Avoid placing components above or below the motor output tracks, as these
components may become effective antennas radiating EMI. If possible, route all 4 motor
outputs in strip-line configuration (above or below a ground plane).

For stringent EMI requirements, it may be necessary to add common-mode inductors on
the motor outputs. Place these filters near the iPOS360x, not near the external connector,
to reduce radiation from the PCB tracks.

Motor outputs must be separated from any nearby track (on the same layer) by a guard
ring / track / area connected to ground. It is recommended to use the same guarding
precaution also for tracks on nearby layers, i.e. use intermediate guard layer(s) connected
to ground. The motor outputs must be treated as first source of noise on the motherboard.
Second source of noise is the current flow between each iPOS360x
and it’s decoupling
V
MOT
capacitor.

For best EMC performance, it is strongly recommended to provide an un-interrupted ground
plane on one of the inner layers.

All GND pins of the iPOS360x are galvanically connected together on-board the iPOS360x.
If the motherboard provides an uninterrupted ground plane, it is recommended to connect
all GND pins to the ground plane, and use the ground plane to distribute GND wherever
needed. If the motherboard does not provide an uninterrupted ground plane, it is best to
use each GND pin for it’s intended purpose, as described in
par. 3.4.3. This will create local
“star point” ground connection on
-board each iPOS360x. For a multi-axis motherboard with
one common power supply for all motors, each motor power supply return track shall be
routed separately for each iPOS360x, and star-point connected at the power supply
terminal.

The following signal pairs must be routed differentially, i.e. using parallel tracks with minimal
loop area: A+/Sin+ , A-/Sin- ; B+/Cos+ , B-/Cos- ; Z+ , Z- ; CAN-Hi , CAN-Lo.

CAN-Bus tracks must be routed with a bus topology, without branches / bifurcations, in a
daisy-chain fashion. The bus ends must be at the termination resistor(s) and/or external
connectors.

When using +5V
OUT
as supply for external devices (like encoders, Hall sensors, etc.)
provide extra filtering and protection: use series resettable (PTC) fuses to add short-circuit
protection; use transient absorbers to protect against ESD and over-voltage; add high-
frequency filtering to protect against external noise injected on +5V
OUT
.

The outer box / case / cabinet must be connected to the motherboard ground either
galvanically (directly) or through high-frequency decoupling capacitors, rated at an
appropriate voltage.