The DC-BUS technology enables network power line communication of Data, Voice, Music and Video by digital means over Direct Current (DC) battery power lines.
Yamar’s unique technology enables advanced digital communication in hostile and noisy environments such as on vehicle battery lines in a small size silicon device. Customers integrate the devices into modules utilizing their own application (e.g. within body and power train modules for in-vehicle multiplex communication networks). The DC-BUS is used in many non automotive applications too.
The same power line can be used for multiple independent networks by using different carrier frequencies.
Any of Yamar's PLC devices is coupled to powerline using a small footprint DC blocking capacitor, typically 2.2nF. The Ccoupling voltage rating depends on the powerline voltage and its expected impulses.
Yes! it's possible to couple to AC power lines using two capacitors, one for the phase and one for the return.
It is recommended to realize the communication network over a known point-to-point dedicated AC power line.
For more details see: TRANSFERRING UART/LIN/CAN/SPI/DMX/RDM OVER AC POWER LINES
Any Power-supply has a filtering capacitors at its DC inputs. These capacitors attenuate strongly the PLC device carrier signal. It is recommended to add an inductor (>22uH) or ferrite bead (>100Ω @ 5MHz-30MHz) in series to the power-supply connection to the DC powerline to reduce the carrier signal attenuation.
The cable length depends mainly on AC loads impedance connected to the power line. A 10A motor is a small load, but a filtering capacitor of 10nF is a high load.
Yamar's proudct lines have selectable carrier frequencies in the range of 5MHz to 30MHz with TX output level of 1Vpp/2Vpp. and sensitivity of ~10mVpp. A typical distance is up to 100m.
For more application specific information, you can contact our support team.
There is no physical limitation for the number of nodes, but in practice 16-32 nodes is a reasonable number.
Yamar's powerline communication (PLC) transceivers can interface with UART/LIN/CAN/SPI/I2C protocols. The idea is to enable seamless interfacing, proving a transparent physical layer to an existing common communication protocols. The integration of Yamar's PLC ICs is quick and simple, allowing plug & play solution for any application.
The SIG family devices operates up to 115.2Kbit/s. The DCB family devices operates up to 1.4Mbit/s.
The SIG family devices transfers UART/LIN bytes over the power line (Byte oriented transceiver). The data bytes are transferred each one separately over the power line with a fix latency of 2.5/4 bits. Any number of bytes can be transferred. The modulation is multiple phase shifts QPSK. When operating as a network, a master-slave protocol such as LIN can be used.
The DCB family devices are message oriented device. A message of any length is constructed into powerline frame/s and transferred over the power line to the receiving devices. The DCB family has CSMA & Arbitration built-in mechanism for multi-master network operation. The DCB family devices enables seamless interfacing to UART/SPI/I2C/CAN protocols.
Yes. Two or more data buses can operate over the same power line, each using different carrier frequencies. The SIG60 and SIG61 have 7 selectable carriers. The SIG100, SIG102, DCAN500 DCB1M, and DMX250 have 251 selectable carriers.
Each network's carrier frequency shall be selected with the minimal spacing specified (see datasheets) and asymmetric selection (harmonic-wise).
For example, for the DCB1M minimum spacing is 1.5MHz, then the user can select 5MHz, 7.3MHz, 13.7MHz, etc.
The DC-BUS was designed to operate on ordinary wires. Using low capacitance wire such as twisted pair cables, UTP, improve the effective communication length and performance, but defiantly not a requirement.
The communication is not affected by the diode bridge because the carrier signal level is less than 2Vpp and it passes through the diode bridge.
The Multiphase modulation is a unique type of QPSK modulation developed by Yamar. It is based on multiple combinations of phases and provides excellent performance even when the communication channel is noisy.
Yes. The schematic in the datasheet is recommended. Don’t forget to add an inductor >22uH to your power supply before connecting it to the power line. The inductor is needed to ensure that the power supply filtering capacitor will not short (attenuate) the carrier signal to GND.
Yes. Adding a coupling capacitor between the two power lines will enable communication between the devices.
Access to any device internal registers is made by entering command mode and sending pre-defined bytes for write and read registers operations. Please refer to each device datasheet for more details.
For example, in SIG60 device:
When the HDC pin is low, the HDI and HDO pins communicate with the internal registers (Command mode is active). The SIG60 detects the uC bit rate (9.6Kbit/s, 19.2Kbit/s, 38,4Kbit/s, 57.6Kbit/s, and 115Kbit/s). After lowering the HDC pin, send the Read or Write command via the uC serial port as described in the datasheet.
It is important to wait until the uC finishes transferring its data bytes to the SIG60 (depending on the UART bit-rate) before raising the HDC pin. With the Read command, the SIG60 responds immediately (<1uS) after the end of the command. Check the SIG60 datasheet, at the SIG60 page or in the support page under the Datasheet section.
The easiest way is to use the message generator that Yamar supplies (see below) or, use the format as described in the SIG61 datasheet (can be found in the support page under the datasheet section).
Using discrete filters does not reduce the communication performance, because the attenuation of a discrete filter is only 3dB while a ceramic filter attenuation may go to 6dB. However, if several carriers are used for different power line networks, some cross talk may occur.
International Symposium for Design and Technology of Electronics Packages (SIITME)