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Description

Capacitor Electrolytic 100uF 10V Aluminum Radial

Capacitor Electrolytic 220uF 50V

Diode Transorb 33V 600W BI-DIR SMB

Diode Ultrafast 100V 1A

Inductor Power Unshielded 470uH SMD

Resistor 715 OHM 1/10W 1% 0603 SMD

Resistor 240 OHM 1/10W 1% 0603 SMD

Resistor 10 Ohm 1W 5% Metal Oxide

Voltage Regulator 5 Volt

3.5

PLC Device Interface

This section describes the circuitry directly connected to the Cypress PLC device (U2) and not part of the transmitter

and receiver circuitry described above. In the schematic shown in

are not required for the final system. However, they are useful for status indication and debugging. The BOM for this

circuit is shown in

components are the same as for the high voltage board, except that the component numbering is different.

The 32.768 kHz crystal (Y1) is required for PLC communication because it is used for the precise timing of the

network protocol and if selected, is also used for the timing of the FSK modulator and demodulator. On the other

hand, the 24.00 MHz oscillator (Y2) is not required in most designs. It is provided as an optional clock source for

timing the FSK modulator and demodulator because it generates a tighter frequency spectrum, which may help with

designs that are marginal to meeting the FCC or CENELEC conducted emissions requirements. The selection

between the FSK modem source is made by setting the CLKSEL pin ('1' = 32.768 kHz crystal,

'0' = 24.00 MHz oscillator, internal pull-up).

Resistor R9 and capacitor C6 form a low pass filter that is used to filter the received 2400 bps demodulated signal,

which is output on pin RXCOMP+. The filtered signal is then connected to the pin RXCOMP-, where it is furthered

filtered and then deserialized.

Capacitors C11, C22, C26, and C39 are used for decoupling noise from the power supply. Similarly, C7 provides a

cleaner signal from the crystal to the device, and C18 provides a cleaner internal analog ground reference for the

modem.

The I2C interface requires pull-up resistors on the bus. If the external host does not have pull-up resistors, then R35

and R36 should be used. The recommended value for these resistors is 2.4-7.5 k.

The LEDs are optional for PLC status indication (DS2 = receiving, DS3 = transmitting, DS4 = band-in-use detection).

The resistors (R15, R16, and R49) associated with these LEDs are for current limiting.

The DIP switch bank S2 is optional for setting the device's PLC address and I2C address, as well as selecting the

modem's clock source. Push-button S1 with current-limiting resistor R2 is optional and is used to easily reset the

device to the default state, instead of disconnecting and reconnecting power.

www.cypress.com

Table 6. Power Supply BOM for Low Voltage PLC Board

Designator

C24

C25

D10

R45

R46

R54

Table

7. It separates the required components from the optional components. Note that the key

Document No. 001-55427 Rev. *E

Cypress Powerline Communication Board Design Analysis

Qty.

Value

Manufacturer

100 µF

PANASONIC

220 µF

PANASONIC

Littelfuse

ES1B

Diodes Inc.

470 uH

Pulse

715

Rohm

240

Rohm

10, 1 W

Stackpole

LM317MDT

ST Micro

Figure

10, there are many components shown that

MFGPN

Vendor

ECA-1AM101

Digikey

P5123-ND

ECA-1HM221

Digikey

P5183-ND

SMBJ33CA

Digikey

SMBJ33CALFCT-ND

ES1B

Digikey

ES1B-FDICT-ND

P0752.474NLT

Digikey

553-1071-1-ND

MCR03EZPFX7150

Digikey

RHM715HCT-ND

MCR03EZPFX2400

Digikey

RHM240HCT-ND

RSMF 1 10 5% R

Digikey

RSMF110JRCT-ND

LM317MDT-TR

Digikey

497-1574-1-ND

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