technical reference
51
SYNRAD OEM v30 Operator’s Manual Version 2
Interface connections
RJ45 input circuitry
The Interface B (RJ45) connector has two user inputs—a PWM input and an enable input. As described
in the prior table, PWM Positive and PWM Negative are optoisolated to fully isolate PWM Command
signals from other inputs and outputs. The Laser Enable input is ESD protected, but is not optoisolated,
so this input signal must be conditioned by the user.
Figure below illustrates the input circuit’s equivalent internal schematic while below on the following
page provides RJ45 input circuit specifications.
Figure 4-12
RJ45 input equivalent schematic
Warning
serious
personal
injury
Always use shielded cable when connecting your PWM Command
signal source to PWM Positive/PWM Negative inputs. In electrical-
ly-noisy environments, long lengths of unshielded wire act like an
antenna and may generate enough voltage to trigger uncommanded
lasing.
RJ45 (
INTERFACE B
) CONNECTOR – INPUT PINS
PWM POSITIVE (+) (
1
)
PWM NEGATIVE (–) (
6
)
LASER ENABLE (
7
)
GND (
8
)
100 Ohm
FIRESTAR v30
INPUT CIRCUITRY
430 Ohm
EMI Filter
