© National Instruments Corp. 5 FP-PWM-520 and cFP-PWM-520
Install a 2A maximum, fast-acting fuse between the external
power supply and the VSUP terminal on each channel. Install
a1 A maximum, fast-acting fuse suitable for the load at the
VOUTterminal. Figure 3 shows fuses where appropriate.
Figure 3. Wiring the [c]FP-PWM-520
Caution Maximum output current for the cFP-PWM-520
is lower than 1A if the module is operating in the
50–70°C temperature range. Refer to the Specifications
section for more information, and select fuses for the VOUT
terminals accordingly.
Pulse-Width Modulator Output Circuit
The [c]FP-PWM-520 output channels are optically isolated from
the rest of the FieldPoint bank. The channels are sourcing outputs
with short-circuit protection circuitry. Sourcing current means that
the VOUT terminal provides a path to a voltage supply. In the ON
state of the output period, a transistor is turned on between VSUP
and VOUT. In the OFF state, this transistor is turned off, allowing
only a small leakage current to flow.
C V
V
SUP
V
OUT
[c]FP-PWM-520
COM
Protected
Sourcing
Output
+
–
Load
5 VDC or
10–30 VDC
External
Power Supply
COM
2
A
M
ax
User-Supplied
Fuse
1 A Max
User-Supplied
Fuse