AN55427 Cypress Powerline Communication Board Design Analysis Associated Project: No Associated Part Family: CY8CPLC10, CY8CPLC20 Software Version: NA Related Application Notes: None To get the latest version of this application note, or the associated project file, please visit http://www.cypress.com/go/AN55427. This application note describes the on-board circuitry of Cypress’s high voltage 110 V to 240 V AC Powerline Communication (PLC) boards (CY3274). It describes the filter, coupling circuit, and power supply design. It also explains the selection of critical components necessary to meet performance and compliance requirements. Contents Introduction Introduction ....................................................................... 1 High Voltage Board Design ............................................... 2 Transmit Signal Path .................................................... 5 Receive Signal Path ..................................................... 6 Signal Path Component Requirements ........................ 6 Power Supply ............................................................... 7 Power Path Component Requirements ........................ 9 PLC Device Interface ................................................. 10 Low Voltage Board Design .............................................. 12 Transmit Signal Path .................................................. 13 Receive Signal Path ................................................... 13 Signal Path Component Requirements ...................... 14 Power Supply ............................................................. 14 PLC Device Interface ................................................. 15 Summary ......................................................................... 17 Worldwide Sales and Design Support ............................. 19 Powerlines are widely available communication media for PLC technology all over the world. The pervasiveness of powerline also makes it difficult to predict the characteristics and operation of PLC products. Because of the variable quality of powerlines around the world, implementing robust communication over powerline has been an engineering challenge for years. The Cypress PLC solution enables secure and reliable communication over powerline. The features of Cypress PLC include: Integrated Powerline PHY modem with optimized filters and amplifiers to work with lossy high voltage and low voltage powerlines. Powerline optimized network protocol that supports bidirectional communication with acknowledgement based signaling. In case of data packet loss due to louder noise on the powerline, the transmitter has the capability to retransmit the data. The powerline network protocol supports 8-bit CRC for error detection and data packet retransmission. A Carrier Sense Multiple Access (CSMA) scheme is built into the network protocol; it minimizes collision between packet transmissions on the powerline, supports multiple masters, and enables reliable communication on a bigger network. A block diagram of the PLC solution with the CY8CPLC20 programmable PLC chip is shown in Figure 1. To interface the device to the powerline, a coupling circuit is required. www.cypress.com Document No. 001-55427 Rev. *C 1 Cypress Powerline Communication Board Design Analysis Figure 1. Cypress PLC Solution Block Diagram The CY3274 kits are used to develop a powerline controller and embedded host application on the CY8CPLC20 Programmable PLC device. They contain many user interface options such as I2C, RS232, GPIO, analog voltage, LCD display, and LED to develop a full application. The following sections describe the design of the filter circuits and power supplies, including the selection of critical components for meeting performance and compliance requirements. High Voltage Board Design This section describes the design of the high voltage (110 V AC to 240 V AC) PLC boardCY3274. Cypress provides the CY3274 High Voltage Programmable PLC Development Kit (DVK)for evaluating the Cypress PLC solution. The CY3274 is designed with the filtering and power supply circuitry to operate on 110-240 V AC powerlines. They are compliant to the following CENELEC and FCC standards: Powerline Signaling (EN50065-1:2001, FCC Part 15) Safety (EN60950) Powerline Immunity EN61000-3-2/3) www.cypress.com (EN50065-2-1:2003, The design includes all circuitry to meet the requirements for signaling on high voltage lines according to the EN50065-1:2001 standard. The high voltage boards include an isolated offline switch mode power supply accepting input voltages in the range of 110-240 V AC, and 50-60 Hz line frequency, operating off the same powerlines that carry the communication signaling. The design contains transmit signal filtering and amplification to meet the conducted emissions requirements of the CENELEC and FCC standards. It also has receive signal filtering and signal isolation external to the Cypress PLC device. This provides a compact and low cost implementation that is adaptable to a wide variety of PLC applications. The schematic in Figure 2 shows the Cypress high voltage board’s transmit filter and amplification, receive filter, and coupling circuit to the high voltage powerline. The Bill of Materials (BOM) of these components is listed in Table 1. Document No. 001-55427 Rev. *C 2 Cypress Powerline Communication Board Design Analysis Figure 2. Cypress High Voltage PLC Board Signal Filtering, Amplification, and Coupling Circuit www.cypress.com Document No. 001-55427 Rev. *C 3 Cypress Powerline Communication Board Design Analysis Table 1. Cypress High Voltage PLC Board Signal Filtering, Amplification, and Coupling BOM Description Designator Qty. Value Manufacturer Manufacturer Part# Vendor VPN High Voltage Coupling Circuit Capacitor Metal Poly Film 0.15uF 300VAC X1 Isolation Transformer Transient Voltage Suppressor 400W 12V BIDIRECT SMA C9 1 T1 D10 0.15 µF Panasonic ECQ-U3A154MG Digikey P11117-ND 1 Precision Components, Inc. 0505-0821G http://www.pcitransformers.com 1 Micro Commercial Co SMAJ12CA-TP Digikey SMAJ12CA-TPMSCT-ND Transmitter Circuit Transmit Amplification Capacitor Ceramic 1.0uF 16V X7R 0603 Capacitor Ceramic 0.10uF 10% 16V X7R 0603 Capacitor Ceramic 10.0uF 10% 25V X5R 1206 Capacitor Ceramic 0.01uF 25V X7R 0603 Transistor NPN HV 40V 1A SOT-89 Transistor PNP HV 40V 1A SOT-89 Transistor NPN SOT-23 Resistor 22.1 1% 1/10W 0603 Resistor 10.0k 1% 1/10W 0603 C12, C13, C14, C15 4 1.0 µF Taiyo Yuden EMK107B7105KA-T Digikey 587-1241-1-ND C18, C24 2 0.1 µF Panasonic ECJ-1VB1C104K Digikey PCC1762CT-ND C19 1 10.0 µF Taiyo Yuden TMK316BJ106KL-T Digikey 587-1337-1-ND C36 1 0.01 µF AVX 06033C103JAT2A Digikey 06033C103JAT2A-ND Q1 1 Zetex FCX491ATA Digikey FCX491ACT-ND Q2 1 Zetex FCX591ATA Digikey FCX591ACT-ND Q3 1 Fairchild MMBT3904LT1 Digikey MMBT3904LT1INCT-ND R14 1 22.1 Yageo RC0603FR-0722R1L Digikey 311-22.1HRCT-ND R15, R17, R18, R28, R29, R30, R31 7 10.0 k Yageo RC0603FR-0710KL Digikey 311-10.0KHRTR-ND 1 4.02 k Yageo RC0603FR-074K02L Digikey 311-4.02KHRCT-ND 1 4.99 Yageo RC0603FR-074R99L Digikey 311-4.99HRCT-ND 1 1.00 k Yageo RC0603FR-071KL Digikey 311-1.00KHRTR-ND National Semiconductor LMH6639MF/NOPB Digikey LMH6639MFCT-ND Panasonic ECJ-1VB1C104K Digikey PCC1762CT-ND AVX 06033A102FAT2A Digikey 06033A102FAT2A-ND Resistor 4.02k 1% R16 1/10W 0603 Resistor 4.99 1% R23 1/10W 0603 Resistor 1.00k 1% R25 1/10W 0603 Op-Amp 190MHz U4 Transmit Filtering for FCC/CENELEC Capacitor Ceramic 0.10uF 10% 16V C16, C17 X7R 0603 Capacitor Ceramic C20, C21, 1000PF 1% 5V NP0 C22, C23 0603 Resistor 37.4k 1% R19, R20 1/10W 0603 Resistor 3.83k 1% R21 1/10W 0603 Resistor 7.50k 1% 1/10W 0603 Resistor 36.5 1% 1/10W 0603 Resistor 41.2 1% 1/10W 0603 Op-Amp 190MHz 1 2 0.1 µF 4 1.0 nF, 1% 2 37.4 k Yageo RC0603FR-0737K4L Digikey 311-37.4KHRCT-ND 1 3.83 k Yageo RC0603FR-073K83L Digikey 311-3.83KHRCT-ND R22 1 7.50 k Yageo RC0603FR-077K5L Digikey 311-7.50KHRTR-ND R26 1 36.5 Yageo RC0603FR-0736R5L Digikey 311-36.5HRCT-ND R27 1 41.2 Yageo RC0603FR-0741R2L Digikey 311-41.2HRCT-ND U2, U3 2 National Semiconductor LMH6639MF/NOPB Digikey LMH6639MFCT-ND C10 2 0.01 µF AVX 06033C103JAT2A Digikey 06033C103JAT2A-ND C41 1 1500 pF Yageo CC0603KRX7R9BB152 Digikey 311-1184-2-ND D6 1 ST Micro BAT54SFILM Digikey 497-2522-1-ND L5 1 1 mH Taiyo Yuden CB2518T102K Digikey 587-2195-1-ND R10 1 2.0 k Yageo RC0603FR-072KL Digikey 311-2.00KHRCT-ND R9, R11 2 20.0 k Yageo RC0603FR-0720KL Digikey 311-20.0KHRCT-ND Receiver Circuit Capacitor Ceramic 0.01uF 25V X7R 0603 Capacitor Ceramic 1500pF 10% 50V X7R 0603 Dual Schottky Diode Inductor 1mH 10% 1007 Resistor 2.0k 1% 1/10W 0603 Resistor 20.0k 1% 1/10W 0603 www.cypress.com Document No. 001-55427 Rev. *C 4 Cypress Powerline Communication Board Design Analysis Transmit Signal Path Transmit Filter The FSK transmit signal TX is generated on the FSK_OUT pin of the Cypress PLC device as a low amplitude (~125 mVp-p), unfiltered signal. This signal is applied to the input of an external transmit filter block consisting of opamps U2 and U3, and their related passive components. The transmit filter is a fourth order Chebyshev response band pass filter, designed for 1.5 dB maximum pass band ripple. It provides 16.5 dB of gain at the center frequency of 133 kHz, suppression of -20 dBc at the 150 kHz band limit, and -50 dBc and -60 dBc at the second and third carrier harmonics, respectively. The transmit filter response is shown graphically in Figure 3. Figure 3. Cypress High Voltage PLC Board Transmit Filter Response The power supply for the transmit filter opamps is a filtered version of the VPWR supply. This prevents the relatively large currents produced by the power amplifier from feeding back into the high-Q filter circuit through the power supply and causing oscillations. Hence, it is advisable to avoid routing the high current transmit signal near the filter circuit. T r a n s m i t Am p l i f i c a t i o n The filtered transmit data signal is applied to the power amplifier, which consists of opamp U4, transistors Q1 and Q2, and associated passive components. The power amplifier provides an additional 12 dB voltage gain, and is capable of driving low impedance loads presented by the powerline. When the device is not actively transmitting, the signal TX_DISABLE is asserted from the PLC device. This disables the external power amplification circuitry to save power and make the transmit amplification circuit have a high impedance so that the receive signal is not attenuated. Note that the transmit filter stage amplifiers U2 and U3 are always enabled, so that there is no spurious noise output on the line due to filter ringing at startup. High Voltage Coupling The transmit signal from the power amplifier is driven on to the powerlines via the isolation transformer T1. Capacitor C14 provides DC isolation for the transmitter on the device side, and C9 provides line frequency isolation on the line side. www.cypress.com Document No. 001-55427 Rev. *C 5 Cypress Powerline Communication Board Design Analysis Receive Signal Path The receive signal is coupled from the line into the kit via the same isolation transformer, T1, as is used by the transmitter. R e c e i ve F i l t e r Capacitor C10 provides DC isolation. Resistor R10 provides a signal input impedance for the receiver. This resistor, in combination with D6, provides signal limiting to protect the receiver circuitry from high amplitude transmitter signals and any large signals coupled in from the line. The receive filter comprised of L5 and C41, in combination with R10, provides some rejection of out-ofband interference, such as AM broadcast signals. This interference may be coupled from the line and would otherwise swamp the PLC device’s internal receiver circuitry. The response of the receive filter is shown in Figure 4. Resistors R9 and R11 set the VCC/2 bias voltage required on the receive pin of the PLC device. Figure 4. Cypress High Voltage PLC Board Receive Filter Response Signal Path Component Requirements The values of the transmit filter passive components are relatively critical; 1% tolerance parts should be used to ensure an accurate response. The opamps used in the transmit filter implementation must meet the following requirements: Gain Bandwidth (GBW) > 50 MHz Voltage feedback VDD - VSS ≥ 12 V Power Supply Rejection Ration (PSRR) > 70 dB Total Harmonic Distortion (THD) < -60 dB www.cypress.com The coupling transformer T1 must provide a low DC resistance (<0.5 ), low leakage inductance (<12 H) to minimize signal loss and isolation, consistent with safety requirements per EN60950 specification. The signal coupling transformer, T1, used in the CY3272 provides 3750 V isolation, a DC resistance of <0.35 and a leakage inductance less than 1 H. Capacitor C9 must be X1 or X2 rated to accommodate the turn-on surge, which occurs when power is applied to the device, as well as surge immunity according to EN 61000-4-5 and EN 50065-2-1 standards. The capacitor C9, used in the high voltage board design is a 300 V AC Panasonic ECQUG series metalized polyethylene film device, which is rated for direct across-line application, accommodating the surge requirements of the previously mentioned specifications. Document No. 001-55427 Rev. *C 6 Cypress Powerline Communication Board Design Analysis Power Supply This section describes the power supply design for the high voltage boards. The schematic of the power supply is shown in Figure 5. The BOM of the power supply is listed in Table 2. The offline switch mode power supply on the high voltage boards is a standard isolated flyback converter. Bridge rectifier D7 produces a rectified input from the AC line, which is used to drive the primary side of the converter. Capacitors C30 and C31 provide charge storage to guarantee a sufficiently high input voltage to operate the converter throughout the entire AC line cycle. C30 and C31, in combination with T3, minimize the conduction of power supply switching transients onto the AC line. R41 provides in-rush current limiting. Inductor L3 and capacitor C29 provide isolation to prevent the 133 kHz transmitter signal from riding the AC line voltage into the rectifier, creating harmonic energy on the AC lines. The inductor also presents a high impedance to the powerline so that the power supply does not load the PLC signal. These components provide an additional measure of protection for both conducted immunity and conducted radiation. An iWatt iW1690 power controller manages the power conversion. Startup current for the device is provided on its Vin pin via resistors R32 and R34. When it starts operating, power and regulation voltage sensing is provided to the controller by the auxiliary secondary winding of T2. Figure 5. Cypress High Voltage PLC Board Power Supply Circuit www.cypress.com Document No. 001-55427 Rev. *C 7 Cypress Powerline Communication Board Design Analysis Table 2. Cypress High Voltage PLC Board Power Supply BOM Description Capacitor Ceramic 10.0uF 10% 25V X5R 1206 Capacitor Ceramic 0.10uF 10% 16V X7R 0603 Capacitor Ceramic 470PF 250VAC X1Y1 RAD Capacitor Metal Poly Film 0.022uF 300VAC X1 Capacitor Electrolytic 4.7uF, 400V Designator Quantity NPN Silicon Planar Medium Power High-Gain Transistor Resistor 750k 1% 1206 Resistor 10.0k 1% 1/10W 0603 Resistor 820k 1% 1206 Resistor 3.9 Ohm 1% 0805 Resistor 68.0k Ohm 1/8W 1% 0805 Resistor 1.00 Ohm 1/10W 1% 0603 Resistor 100k 1/10W 1% 0603 Resistor 12.0K 1/10W 1% 0603 Resistor 6.8k, 1% 0603 RESISTOR 10.0 OHM 5W 5% WIREWND Power Trasnsformer EE-16 24mH Common Mode Choke Voltage Regulator 5 Volt Off-Line Switcher Manufacturer Manufacturer Part# VPN 2 10.0 µF Taiyo Yuden TMK316BJ106KL-T Digikey 587-1337-1-ND C27, C34 2 0.1 µF Panasonic ECJ-1VB1C104K Digikey PCC1762CT-ND C28 1 470 pF TDK CD95-B2GA471KYNS Digikey 445-2407-ND C29 1 0.022 µF Panasonic ECQ-U3A223MG Digikey P11112-ND C30, C31 2 4.7 µF, 400 V Nichicon UVR2G4R7MPD Digikey 493-1229-ND 4.7 µF, 400 V United Chemi-Con EKMG401ELL4R7MJ16S Digikey 565-1411-ND C32 1 330 µF, 16 V Nichicon UPW1C331MPD Digikey 493-1784-ND C35 1 10 µF, 50 V Nichicon UPW1H100MDD Digikey 493-1890-ND D7 D8, D9 1 2 Fairchild Diodes Inc DF10S B1100-13-F Digikey Digikey DF10SCT-ND B1100-FDICT-ND L3 1 1.5 mH Taiyo Yuden LHL08TB152J Digikey LHL08TB152J-ND L4 1 22 uH Taiyo Yuden CBC3225T220MR Digikey 587-1626-1-ND Q4 1 TSC TS13003HVCT mouser.com 821-TS13003HVCT Q4 (2nd Source) R32 R33 R34 R35 1 1 1 1 750 k, 1% 10.0 k 820 k, 1% 3.9 ST Micro Yageo Yageo Yageo Yageo STX616-AP RC1206FR-07750KL RC0603FR-0710KL RC1206FR-07820KL RC0805FR-073R9L Digikey Digikey Digikey Digikey Digikey 497-7625-1-ND 311-750KFRCT-ND 311-10.0KHRTR-ND 311-820KFRCT-ND 311-3.90CRCT-ND R36 1 68k, 1% Yageo RC0805FR-0768KL Digikey 311-68.0KCRTR-ND R37 1 1.0 Yageo RC0603FR-071RL Digikey 311-1.00HRCT-ND R38 R39 R40 1 1 1 100 k 12 k, 1% 6.8 k, 1% Yageo Yageo Yageo RC0603FR-07100KL RC0603FR-0712KL RC0603FR-076K8L Digikey Digikey Digikey 311-100KHRTR-ND 311-12.0KHRCT-ND 311-6.80KHRTR-ND R41 1 10, 5 W Vishay AC05000001009JAC00 Digikey PPC5W10.0CT-ND T2 T2 (2nd Source) T3 T3 (2nd Source) U5 U6 1 3.2 mH 1 24 mH Shenzen Goldenway Renco Electronics Shenzen Goldenway Renco Electronics ST Micro iWatt EE-16 (5+5) (rev-A) RLCY-1014 EE8.3(2+2)-hori, (rev-A) RLCY-1013 LD1117S50CTR iW1690-07 e-mail:[email protected] e-mail:[email protected] e-mail:[email protected] e-mail:[email protected] Digikey 497-1243-1-ND e-mail:[email protected] 1 1 Switching transistor Q4 is operated directly by the iW1690. Switch current is sensed across resistor R35. The switching frequency of the iW1690 is approximately 75 kHz. The basic cycle-by-cycle operation of the power converter is described briefly in the following paragraph. The voltage on each of the rectified secondary outputs is determined by the primary voltage, the turns ratio of the transformer, and the switch duty cycle, as follows: Vout With Q4 switched ON, current is pulled from the line through the primary winding of T2. Diodes D8 and D9 ensure that the secondary windings of T2 do not conduct current during the switch ON time and energy is stored in the magnetic field of T2. With Q4 switched OFF, the voltage polarity across the primary and secondary windings of T2 is reversed, causing D8 and D9 to be forward biased. Current now flows in the secondary windings, delivering energy to the loads. Bulk filter capacitance is provided on the main secondary output by C32. The auxiliary secondary output is filtered at C35 to power the controller. The auxiliary secondary voltage is monitored by the converter at its Vsense pin. This voltage is used to implement output secondary voltage regulation by setting the switch duty cycle. www.cypress.com Vendor C26, C33 C30, C31 (2nd source, 105C) Capacitor Electrolytic 330uF 16V 20% Capacitor Electrolytic 10uF 50V 20% Full Wave Diode Bridge Schottky Diode 100V 1A SMA Inductor 1500uH 0.2A 5% Radial Inductor 22uH 20% 1210 Value Document No. 001-55427 Rev. *C D * N *Vin (1 D) Equation 1 8 Cypress Powerline Communication Board Design Analysis Where, N is the secondary or primary turns ratio and D is the switch duty cycle. The nominal turns ratio for both secondaries of T2 is 0.13. As the input voltage varies over the course of an AC line cycle, the power controller varies D to maintain a constant voltage on the secondary supplies. Because the voltages of the secondary outputs are related by the turns ratios, it is possible to regulate multiple, isolated outputs by monitoring just one of the secondaries. In this case, the controller regulates the main output by monitoring its own supply winding. The voltage produced at C32 is approximately 10 V. This voltage is filtered via L4/C33 to further reduce switching noise and produce the VPWR supply, which drives the transmitter circuitry. The 10 V supply is also applied to the input of linear regulator U5, which produces a 5 V VDD power supply for the Cypress PLC device and optionally, an external controlling device. Capacitor C29 must be X1 or X2 rated to accommodate the turn on surge, which occurs when power is applied to the device, as well as surge immunity according to EN 61000-4-5 and EN 50065-2-1. The capacitor used in the high voltage board design is a 300 V AC Panasonic ECQUG series metalized polyethylene film device, which is rated for direct across-line application. It accommodates the surge requirements of the specifications mentioned earlier. Power Path Component Requirements It is important to note that a bleeder resistor may need to be used, depending on the discharge path for the PLC coupling capacitor C9. When power is disconnected, this capacitor will still be charged unless it can discharge through the power supply. In the Cypress high voltage boards, it was tested that the voltage discharges quickly enough to meet the safety requirements of CENELEC EN60950. However, other power supplies may not discharge the voltage quickly enough and in that case, a bleeder resistor (> 1 M 0.25 W, working voltage >360 V DC) should be used. The power converter is designed for worldwide operation and is expected to operate from line voltages ranging from 90-240 V AC. This results in peak voltages approaching 350 V DC, and hence, filter capacitors C30 and C31 must be rated to accommodate these peak voltages. In the flyback (Q4 OFF) state, the peak voltage generated on the primary winding of T2 (the collector of Q4), strictly as a result of the circuit operation, is higher than Vin. This voltage is given as follows: Vpk Vin (1 D) Equation 2 In addition, transformer leakage inductance results in an additional increase, above Vpk, at Q4 turn off. This results in peak voltages approaching 500 V being possible at the collector of Q4. Resistor R41 should be a high power rated (≥ 3 W), wire wound resistor that can support the surge requirements of the system. L3 should be rated for ≥ 0.2 A of current. Capacitor C28 must be a Y1-rated safety capacitor. The capacitor used in the high voltage board design is a 4000 V AC TDK CD series mid-high voltage ceramic device. This device is rated for direct line-ground applications and accommodates the surge requirements of the previously mentioned specifications. Protection Circuit Basic protection against line transients is provided by transient suppressor D1. The high voltage boards employ a Panasonic ZNR type device with a peak surge current capability in excess of 1000 A and a voltage rating of 275 V AC. This type of device has the advantage of low shunt capacitance, 120 pF in this case, which ensures that it does not degrade the PLC signal. Protection against catastrophic circuit failure is provided by fuse F1, which is a 2 A, 250 V AC Slow-Blow device. This protection circuit is shown in Figure 6 and the BOM is listed in Table 3. Figure 6. Cypress High Voltage PLC Board AC Line Input Protection Circuit www.cypress.com Document No. 001-55427 Rev. *C 9 Cypress Powerline Communication Board Design Analysis Table 3. Cypress High Voltage PLC Board AC Line Input Protection BOM Description Designator Qty. Value Manufacturer Manufacturer Part# Vendor VPN Transorb Voltage Suppressor 430V 1250A ZNR D1 1 430 V Panasonic ERZ-V07D431 Digikey P7251-ND Fuse 2A Slow Blow 250VAC F1 1 2.0 A Bel Fuse RST 2 Digikey 507-1179-ND PLC Device Interface This section describes the circuitry that is directly connected to the Cypress PLC device (U1) and not part of the transmitter and receiver circuitry described above. In the schematic shown in Figure 7, there are many components shown that are not required for the final system, but are useful for status indication and debugging. The BOM for this circuit is shown in Table 4. on page 11. It separates the required components from the optional components. The 32.768 kHz crystal (Y2) 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 (Y1) 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). www.cypress.com Resistor R2 and capacitor C3 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 further filtered and then deserialized. Capacitors C1 and C2 are used for decoupling noise from the power supply. Similarly, C5 provides a cleaner signal from the crystal to the device, and C6 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 R6 and R7 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) and power indication (DS5). The resistors (R1, R3, R4, R5) associated with these LEDs are for current limiting. The DIP switch bank S1 is optional for setting the device’s PLC address and I2C address, as well as selecting the modem’s clock source. Push-button S2 with current-limiting resistor R8 is optional and is used to easily reset the device to the default state, instead of disconnecting and reconnecting power. Document No. 001-55427 Rev. *C 10 Cypress Powerline Communication Board Design Analysis Figure 7. Cypress PLC Device Interface Circuit (on the High Voltage Board) Table 4. Cypress PLC Device Interface BOM (on the High Voltage Board) Description Designator Qty. Value Capacitor Ceramic 0.10uF 10% 16V X7R 0603 Capacitor Ceramic 1.0nF X7R 10% 25V C0603 C1, C5 C2 2 1 Capacitor Ceramic 0.01uF 25V X7R 0603 C3, C4 2 0.01 µF Capacitor Ceramic 1.0uF 16V X7R 0603 Capacitor Ceramic 22pF 100V C0G 0603 C6 C7, C8 1 2 1.0 µF 22 pF Resistor 2.1k 1% 1/10W 0603 R2 1 2.10 k Crystal 32.768kHz 12.5pF Y2 1 32.768 kHz LED Red Clear 0805 LED Green Clear 0805 LED Yellow Clear 0805 Header 5-Pin Locking 0.1Centers DS2 DS3 DS4 J1, J2, J3, J4, P1, P2 J6 Resistor 1.00k 1% 1/10W 0603 R1, R3, R4 3 Resistor 2.70k 1% 1/10W 0603 R6, R7 Resistor 330 1% 1/10W 0603 Resistor 402 1% 1/10W 0603 DIP Switch 5 Position DIP-5 Pushbutton N.O. Oscillator R8 R5 S1 S2 Y1 Header 2-Pin 0.1 Centers Y1 (2nd Source) www.cypress.com Manufacturer Discretes and Crystal 0.1 µF Panasonic 1.0 nF Murata Manufacturer Part# Vendor VPN ECJ-1VB1C104K GRM033R71E102KA01D Digikey Digikey AVX 06033C103JAT2A Digikey Taiyo Yuden Murata EMK107B7105KA-T GRM1885C2A220JA01D Digikey Digikey Yageo RC0603FR-072K1L Digikey ECS Inc. ECS-3X8X Digikey PCC1762CT-ND 490-3184-1-ND 06033C103JAT2AND 587-1241-1-ND 490-1335-1-ND 311-2.10KHRTRND X1123-ND I2C, Jumpers, and LEDs (Optional) 1 Lite-On 1 Lite-On 1 Lite-On LTST-C170KRKT LTST-C170KGKT LTST-C170KSKT Digikey Digikey Digikey 160-1415-1-ND 160-1414-1-ND 160-1416-1-ND 6 Sullins PEC02SAAN Digikey S1012E-02-ND 1 Amp/Tyco 640456-5 Digikey 1.00 k Yageo RC0603FR-071KL Digikey 2 2.70 k Yageo RC0603FR-072K7L Digikey 1 1 1 1 1 330 402 24.00 MHz Yageo Yageo E-Switch E-Switch Crystek RC0603FR-07330RL RC0603FR-07402RL KAJ05LAGT TL3301AF160QG C3290-24.000 Digikey Digikey Digikey Digikey Digikey A19471-ND 311-1.00KHRTRND 311-2.70KHRTRND 311-330HRCT-ND 311-402HRTR-ND EG4429-ND EG2526CT-ND C3290-24.000-ND 24.00 MHz Citizen CSX750FCC24.000M-UT Digikey 300-7214-2-ND Document No. 001-55427 Rev. *C 11 Cypress Powerline Communication Board Design Analysis Low Voltage Board Design This section describes the design of the boards meant for low voltage PLC. These boards are designed to operate on 12-24 V AC/DC powerlines. They are also designed to be low cost and robust systems that do not need to meet any CENELEC or FCC compliance standards. The schematic in Figure 8 shows the Cypress low voltage board’s transmit amplification, receive filter, and coupling circuit to the low voltage powerline. The BOM for designing such a board is listed in Table 5. Figure 8. Low Voltage PLC Board Signal Filter, Amplification, and Coupling Circuit www.cypress.com Document No. 001-55427 Rev. *C 12 Cypress Powerline Communication Board Design Analysis Table 5. Low Voltage PLC Board Signal Filter, Amplification, and Coupling Circuit BOM Description Designator Qty. Value Manufacturer Low Voltage Coupling Circuit Murata TDK Pulse MFGPN Vendor VPN GRM31CR6YA106KA12L MPZ2012S101A P0752.474NLT Digikey Digikey Digikey 490-5524-1-ND 445-1567-1-ND 553-1071-1-ND Capacitor Ceramic 10uF 35V X5R 10% 1206 Ferrite Chip 100 Ohm 4A 0805 Inductor Power Unshielded 470uH SMD C30 L2 L3 1 1 1 10 µF Capacitor Ceramic 0.1uF 25V X7R 0603 Capacitor Ceramic 0.1uF 25V X7R 0603 Capacitor Ceramic 10uF 16V X5R 1206 Capacitor Ceramic 1UF 50V Y5V 0805 Diode Ultrafast 100V 1A Transistor NPN SOT-23 Transistor NPN 45V 3A Transistor PNP 40V 3A Resistor 620 OHM 1/10W 1% 0603 SMD Resistor 4.99 1% 1/10W 0603 1 1 1 1 2 1 1 1 2 1 0.1 µF 0.1 µF 10 µF 1.0 µF ES1B MMBT3904 ZXT690B ZXT790A 620 4.99 AVX AVX TDK Murata Diodes Inc. Fairchild Zetex Zetex Rohm Yageo 06033C104JAT2A 06033C104JAT2A C3216X5R1C106K GRM21BF51H105ZA12L ES1B MMBT3904LT1 ZXT690BKTC ZXT790AKTC MCR03EZPFX6200 RC0603FR-074R99L Digikey Digikey Digikey Digikey Digikey Digikey Digikey Digikey Digikey Digikey 478-3713-1-ND 478-3713-1-ND 445-4052-1-ND 490-3903-1-ND ES1B-FDICT-ND MMBT3904LT1INCT-ND ZXT690BKCT-ND ZXT790AKCT-ND RHM620HCT-ND 311-4.99HRCT-ND Resistor 10.0k 1% 1/10W 0603 Resistor 4.70K OHM 1/10W 1% 0603 SMD Resistor 0.5 1% 1/4W 0805 C1 C9 C10 C31 D2, D3 Q1 Q2 Q3 R3, R4 R5 R13, R23, R37, R39, R48 R25 R27, R28 5 1 2 10.0 k 4.7 k 0.5 1/4 W MCR03EZPFX1002 RC0603FR-074K7L RL1220S-R50-F Digikey Digikey Digikey RHM10.0KHCT-ND 311-4.70KHRCT-ND RL12S.50FCT-ND Op-Amp 190MHz U1 1 LMH6639MF Rohm Yageo Susumu National Semiconductor LMH6639MF/NOPB Digikey LMH6639MFCT-ND Capacitor Ceramic 1500pF 10% 50V X7R 0603 Capacitor Ceramic 0.01uF 25V X7R 0603 Diode Schottky 40V 0.3A SOT-23 Inductor 1mH 10% 1007 Resistor 10.0k 1% 1/10W 0603 Resistor 2.0k 1% 1/10W 0603 C4 C5 D1 L5 R33, R43 R52 1 1 1 1 2 1 1500 pF 0.01 µF BAT54S 1 mH 10.0 k 2.0 k CC0603KRX7R9BB152 06033C103JAT2A BAT54SFILM CB2518T102K MCR03EZPFX1002 RC0603FR-072KL Digikey Digikey Digikey Digikey Digikey Digikey 311-1184-2-ND 06033C103JAT2A-ND 497-2522-1-ND 587-2195-1-ND RHM10.0KHCT-ND 311-2.00KHRCT-ND 470 uH Transmitter Circuit Receiver Circuit Yageo AVX ST Micro Taiyo Yuden Rohm Yageo Transmit Signal Path Receive Signal Path T r a n s m i t Am p l i f i c a t i o n The FSK transmit signal TX is generated on the FSK_OUT pin of the Cypress PLC device as a higher amplitude (approximately 1.55 Vp-p), unfiltered signal. The low voltage boards do not have any transmit filtering, which reduces the BOM cost. There is one output amplification stage, implemented using op-amp U1 and transistors Q2 and Q3, to drive the low impedance load presented by the powerline. Resistors R3 and R4 set a gain of 1x. The receive signal is coupled from the line into the low voltage boards via the same chip bead L2, as is used by the transmitter. When the device is not actively transmitting, it asserts the signal TX_DISABLE. This disables the external power amplification circuitry to save power. This also makes the transmit amplification circuit have a high impedance so that the receive signal is not attenuated. L ow V o l t a g e C o u p l i n g The transmit signal from the power amplifier is driven on to the powerlines via chip bead L2. Capacitor C6 provides DC isolation for the transmitter on the device side. Capacitor C30 provides line frequency isolation on the line side. With inductor L3, capacitor C30 provides a filter to remove out-of-band noise from entering the receiver. www.cypress.com R e c e i ve F i l t e r Capacitor C5 provides DC isolation. Resistor R52 provides a signal input impedance for the receiver. This, in combination with D6, provides signal limiting to protect the receiver circuitry from the relatively high amplitude transmitter signals, including any large signals coupled in from the line. The receive filter comprised of R52, L5, and C4, provides some rejection of out-of-band interference such as AM broadcast signals. This interference may be coupled from the line, and may otherwise swamp the PLC device’s internal receiver circuitry. Resistors R33 and R43 set the VCC/2 bias voltage required on the receive pin of the PLC device. Document No. 001-55427 Rev. *C 13 Cypress Powerline Communication Board Design Analysis Signal Path Component Requirements Power Supply The chip bead L2 is designed specifically for powerline applications and provides a low DC resistance (0.02 ) and high current handling capability (3 A). Its impedance curve is similar to that of a 0.4 H inductor. The transmit capacitors C10 and C30 should be sized so that they match the impedance of the inductor as closely as possible. This reduces the transmit impedance, which increases the driving distance of the system. In this case, C10 and C30 are each 10 F, which yields an equivalent capacitance of 5 F. At 132 kHz, the impedance of this equivalent capacitor matches the inductor to within 0.1 . Capacitor C30 must also be rated to be above the maximum voltage on the powerline. This section describes the power supply design for low voltage boards. The schematic of the power supply is shown in Figure 9 and the BOM for the power supply is listed in Table 6. The opamp U1 used in the transit amplifier section must provide both high speed to minimize crossover distortion, and relatively high output currents to drive the output transistors. Inductor L4 provides high impedance to the powerline so that the power supply does not load the PLC signal. It should be rated to ≥ 200 mA. Resistor R2 limits in-rush current. It should be rated to ≥ 1 W. D9 protects the circuit from voltage transients and D10 rectifies the voltage when AC power is present. Regulator U7 provides a 5 V output, which is used for the PLC device and the transmit amplifier. The 100 µF electrolytic capacitor C24, along with a 10 µF tantalum capacitor and two 0.1 µF ceramic capacitors provide the necessary decoupling for the PLC device, considering the 5 V supply is shared with the transmit amplifier. Figure 9. Power Supply Circuit while designing Low Voltage PLC Board www.cypress.com Document No. 001-55427 Rev. *C 14 Cypress Powerline Communication Board Design Analysis Table 6. Power Supply BOM for Low Voltage PLC Board 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 Designator C24 C25 D9 D10 L4 R45 R46 R54 U7 Qty. 1 1 1 1 1 1 1 1 1 Value 100 µF 220 µF ES1B 470 uH 715 240 10, 1 W LM317MDT 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 Figure 10, there are many components shown that are not required for the final system. However, they are useful for status indication and debugging. The BOM for this circuit is shown in Table 7. It separates the required components from the optional components. Note that the key 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). www.cypress.com Manufacturer PANASONIC PANASONIC Littelfuse Diodes Inc. Pulse Rohm Rohm Stackpole ST Micro MFGPN ECA-1AM101 ECA-1HM221 SMBJ33CA ES1B P0752.474NLT MCR03EZPFX7150 MCR03EZPFX2400 RSMF 1 10 5% R LM317MDT-TR Vendor Digikey Digikey Digikey Digikey Digikey Digikey Digikey Digikey Digikey VPN P5123-ND P5183-ND SMBJ33CALFCT-ND ES1B-FDICT-ND 553-1071-1-ND RHM715HCT-ND RHM240HCT-ND RSMF110JRCT-ND 497-1574-1-ND 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 currentlimiting resistor R2 is optional and is used to easily reset the device to the default state, instead of disconnecting and reconnecting power. Document No. 001-55427 Rev. *C 15 Cypress Powerline Communication Board Design Analysis Figure 10. PLC Device Interface Circuit (on the Low Voltage Board) www.cypress.com Document No. 001-55427 Rev. *C 16 Cypress Powerline Communication Board Design Analysis Table 7. PLC Device Interface BOM (on the Low Voltage Board) Description Designator Qty. Value Manufacturer Discretes and Crystal Capacitor Ceramic 22pF 100V C0G 0603 Capacitor Ceramic 0.01uF 25V C0G 5% 0603 Capacitor Ceramic 0.1uF 25V X7R 0603 Capacitor Ceramic 0.01uF 25V X7R 0603 Capacitor Ceramic 0.1uF 25V X7R 0603 Capacitor Ceramic 1.0uF 16V X7R 0603 Capacitor Ceramic 0.01uF 25V C0G 5% 0603 Capacitor Ceramic 100pF 25V X7R 0603 Capacitor 10uF,10V Resistor 2.1k 1% 1/10W 0603 C2, C3 C6 C7 C8 C11 C18 C22 C26 C39 R9 2 1 1 1 1 1 1 1 1 1 22 pF 0.01 µF 0.1 µF 0.01 µF 0.1 µF 1.0 µF 0.01 µF 100 pF 10 µF, 10 V 2.10k Power Line Controller Crystal 32.768kHz 12.5pF U2 Y1 1 1 CY8CPLC10 32.768 kHz LED Blue LED Green Clear 0805 LED Red Clear 0805 LED Yellow Clear 0805 Header, 2-Pin Header 2-Pin 0.1 Centers DS1 DS2 DS3 DS5 J1 J2 J3, J6, J7, J9, J10 J4 J8 MT1, MT2, MT3, MT4 R2 R14 R15, R16, R49 R35, R36 S1 S2 Y2 Y2 (2nd Source) 1 1 1 1 1 1 Murata TDK AVX AVX AVX PANASONIC TDK AVX Vishay Rohm Cypress Semiconductor ECS Inc. MFGPN Vendor VPN GRM1885C2A220JA01D C1608C0G1E103J 06033C104JAT2A 06033C103JAT2A 06033C104JAT2A ECJ-1V41E105M C1608C0G1E103J 06031A101JAT2A 293D106X9010A2TE3 MCR03EZPFX2101 Digikey Digikey Digikey Digikey Digikey Digikey Digikey Digikey Digikey Digikey 490-1335-1-ND 445-2664-1-ND 478-3713-1-ND 06033C103JAT2A-ND 478-3713-1-ND PCC2354CT-ND 445-2664-1-ND 478-1146-1-ND 718-1121-1-ND RHM2.10KHCT-ND CY8CPLC10 ECS-3X8X Digikey Digikey CY8CPLC10-28PVXI-ND X1123-ND Rohm Lite-On Lite-On Lite-On MOLEX Sullins SML-E12BC7TT86 LTST-C170KGKT LTST-C170KRKT LTST-C170KSKT 09-65-2028 PEC02SAAN Digikey Digikey Digikey Digikey Digikey Digikey 511-1589-1-ND 160-1414-1-ND 160-1415-1-ND 160-1416-1-ND WM18823-ND S1012E-02-ND Sullins CUI, Inc. Amp/Tyco PEC02SAAN PJ-002A-SMT 640456-5 Digikey Digikey Digikey S1012E-02-ND CP-002APJCT-ND A19471-ND Yageo Rohm ROHM Rohm E-Switch E-Switch Crystek Citizen RC0603FR-07330RL MCR03EZPFX4020 MCR03EZPFX1001 MCR03EZPFX7501 TL3301AF160QG KAJ05LAGT C3290-24.000 CSX750FCC24.000M-UT Digikey Digikey Digikey Digikey Digikey Digikey Digikey Digikey 311-330HRCT-ND RHM402HCT-ND RHM1.00KHCT-ND RHM7.50KHCT-ND EG2526CT-ND EG4429-ND C3290-24.000-ND 300-7214-2-ND I2C, Jumpers, and LEDs (Optional) Header 2-Pin 0.1 Centers Power Jack 2.5x5.5mm Male Header 5-Pin Locking 0.1Centers Mounting Hole Resistor 330 1% 1/10W 0603 Resistor 402 OHM 1/10W 1% 0603 SMD Resistor 1.00k 1% 1/10W 0603 Resistor 7.50k 1% 1/10W 0603 Pushbutton Switch DIP Switch 5 Position DIP-5 24MHz Oscillator Blue LTST-C170KGKT LTST-C170KRKT LTST-C170KSKT 5 1 1 4 1 1 3 2 1 1 1 330 402 1.00 k 7.50 k TL3301AF160QG 24.00 MHz 24.00 MHz Summary The on-board circuitry described in this Application note has to be used for designing both High power and Low power PLC designs. It provides explanation on selection of critical components too for meeting performance and compliance requirements. www.cypress.com Document No. 001-55427 Rev. *C 17 Cypress Powerline Communication Board Design Analysis Document History Document Title: Cypress Powerline Communication Board Design Analysis - AN55427 Document Number: 001-55427 Revision ECN Orig. of Change Submission Date Description of Change ** 2759493 FRE 09/03/2009 New Spec. *A 3123303 FRE 12/29/2010 Added the Bill Of Materials for all of the circuits. Added a description of the components that are not in the TX or RX path, and not in the power supply. Added more details for proper selection of critical transmit, receive, and coupling components. Updated the low voltage board receive filter and transmit path capacitors. *B 3366253 ADIY 09/08/2011 Removed reference to CY8CLED16P01, CY3276, and CY3277 Added sub-headings in Transmit Signal Path and Receive Signal Path sections. Updated Figure 9 *C 4525870 ROIT 10/14/2014 Removed reference to obsolete PLC Kits CY3272, CY3273 and CY3275 in all instances across the document. Updated High Voltage Board Design: Updated Figure 2. Updated Power Supply: Updated Figure 5. Updated Power Path Component Requirements: Updated Protection Circuit: Updated Figure 6. Updated Low Voltage Board Design: Updated Figure 8. Updated Signal Path Component Requirements: Updated description (Replaced L1 with L2). Updated Power Supply: Updated Figure 9. Updated to new template. Completing Sunset Review. www.cypress.com Document No. 001-55427 Rev. *C 18 Cypress Powerline Communication Board Design Analysis Worldwide Sales and Design Support Cypress maintains a worldwide network of offices, solution centers, manufacturer’s representatives, and distributors. To find the office closest to you, visit us at Cypress Locations. PSoC® Solutions Products Automotive cypress.com/go/automotive psoc.cypress.com/solutions Clocks & Buffers cypress.com/go/clocks PSoC 1 | PSoC 3 | PSoC 4 | PSoC 5LP Interface cypress.com/go/interface Lighting & Power Control cypress.com/go/powerpsoc cypress.com/go/plc Memory cypress.com/go/memory PSoC cypress.com/go/psoc Touch Sensing cypress.com/go/touch USB Controllers cypress.com/go/usb Wireless/RF cypress.com/go/wireless Cypress Developer Community Community | Forums | Blogs | Video | Training Technical Support cypress.com/go/support PSoC is a registered trademark and PSoC Creator is a trademark of Cypress Semiconductor Corp. All other trademarks or registered trademarks referenced herein are the property of their respective owners. Cypress Semiconductor 198 Champion Court San Jose, CA 95134-1709 Phone Fax Website : 408-943-2600 : 408-943-4730 : www.cypress.com © Cypress Semiconductor Corporation, 2009-2014. The information contained herein is subject to change without notice. Cypress Semiconductor Corporation assumes no responsibility for the use of any circuitry other than circuitry embodied in a Cypress product. Nor does it convey or imply any license under patent or other rights. Cypress products are not warranted nor intended to be used for medical, life support, life saving, critical control or safety applications, unless pursuant to an express written agreement with Cypress. Furthermore, Cypress does not authorize its products for use as critical components in life-support systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress products in life-support systems application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress against all charges. 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Disclaimer: CYPRESS MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARD TO THIS MATERIAL, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. Cypress reserves the right to make changes without further notice to the materials described herein. Cypress does not assume any liability arising out of the application or use of any product or circuit described herein. Cypress does not authorize its products for use as critical components in life-support systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress’ product in a life-support systems application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress against all charges. Use may be limited by and subject to the applicable Cypress software license agreement. www.cypress.com Document No. 001-55427 Rev. *C 19