Microchip Technology PL360G55CB-EK, User Manual

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• Adapt Input/Output impedance for optimal reception/transmission. This is controlled by TXRX0 signal
• A band-pass filtering for received signals
3.3.5.3 PLC Coupling Circuit
PLC coupling circuit connects the PLC signal directly to the mains grid or even to DC power rails without
requiring any hardware adaptation. The main purpose of the circuit is to block the mains voltage of the
grid to/from which the signal is injected/received. This is carried out in PL360G55CB-EK, see
Figure 3-10 ,
by a high voltage capacitor, C103. Resistors R108, R112 and R115 allow the high voltage capacitor to
discharge after disconnection from mains.
CAUTION
PLC coupling components are designed for a maximum voltage of 230 V
AC
or 200 V
DC
.
The TR100 transformer (with turn ratio 1:1) provides galvanic isolation from mains. A non-isolated version
could easily be implemented removing TR100, soldering R106 and R116 resistors and updating the value
of L103 according to the PLCOUP014-NONISO design.
MOV100 varistor, F100 fuse and D102 TVS diode protect the coupling circuit from the overvoltages and
high transient voltages (surges and spikes) from mains.
3.3.5.4 PLC Reception Circuit
The PLC reception circuit used in PL360G55CB-EK, see Figure 3-10 , is the reference design for the
reception stage and it is composed of:
• Single-pole low pass filter, R133 and C109
• Automatic Gain Control (AGC) circuit. A resistor, R134, is used to attenuate the incoming PLC signal
in case its amplitude is high enough to exceed the input dynamic range of the embedded ADC
• A resistor, R132, for impedance matching
• DC decoupling capacitor, C106
3.3.6 Power Supply System
The PL360G55CB-EK board can be powered by several power sources. Supply the board via:
• the DC jack 2.0 mm connector J8, DC_IN , with a DC source from 6V to 30V (±5%) and 4.2W
• the USB connector (+5V), J4
• the power supply pin (+5V) of mikroBUS standard
Table 3-13. Power Sources for PL360G55CB-EK Board
Power Input Voltage Requirements Power Requirements Connector Marking
DC Jack connector +6V to +30V (±5%) 4.2 Watts DC_IN
Target USB +5V
According to USB
specifications
USB
mikroBUS Power pin
(+5V)
+5V
According to mainboard
specifications
+5V
The PL360G55CB-EK board has two voltage rails:
• +3.3V for the digital part of the PLC modem, PL360, and the SAMG55J19 MCU
• +12V to power the class-D amplifier of the PLC coupling circuit
PL360G55CB-EK
PL360G55CB-EK Board
©
2019 Microchip Technology Inc.
User Guide
DS50002871A-page 23