National Semiconductor Corporation today introduced the industry’s first Ethernet transceiver with integrated hardware support for the IEEE 1588 Precision Time Protocol (PTP).

For applications in motion control, instrumentation, data acquisition and telecommunications, the DP83640 precision PHYTER transceiver synchronises the distributed network nodes to a master clock with 8-nanosecond accuracy. This precision synchronisation is critical to high-performance factory automation, test and measurement, and wireless infrastructure systems.

National’s DP83640 precision PHYTER transceiver integrates hardware time stamping of receive and transmit packets, a high-accuracy IEEE 1588 clock and 12 general-purpose input/output (GPIO) pins that handle simultaneous real-time events or multiple triggers.

The DP83640 interfaces with any microcontroller, field-programmable gate array (FPGA) or application-specific integrated circuit (ASIC) with an Ethernet media access controller (MAC).

National is demonstrating its new Ethernet transceiver at the 2007 International IEEE Symposium on Precision Clock Synchronisation in Vienna, Austria, from October 1-3.

Unlike existing software or customised hardware implementations, the DP83640 integrates the IEEE 1588 PTP functionality in the physical layer. It records the timestamps as close to the wire as possible, with an 8 ns resolution, to yield the highest accuracy for precision control and the lowest jitter for data acquisition. 

By using one of four clock update algorithms the user adjusts the on-board PTP clock to 1-part-per-billion (ppb) accuracy. In addition, a high-precision frequency-controlled oscillator generates a low-jitter, selectable-frequency clock output from the PTP clock.  The transceiver also synchronises the GPIOs directly with the timestamp engine and the PTP clock to extend this accuracy throughout the real-time system.

“Devices that require close coordination of events, such as industrial controllers, are increasingly interconnected by Ethernet and synchronised using protocols such as IEEE 1588 Precision Time Protocol,” said Alexandra Dopplinger, industrial segment marketing manager Freescale’s Network Computing and Systems Group. 

“National’s Precision PHYTER transceiver allows customers to implement IEEE 1588 solutions with any ColdFire microcontroller or PowerQUICC communications processor that doesn't already have that capability.''

The Precision PHYTER also may be used with some IEEE 1588-enabled processors to further improve clock synchronisation accuracy for applications such as test and measurement."

The first reference board to implement the DP83640 precision PHYTER transceiver with an MCF5234 ColdFire microcontroller may be ordered from Freescale as M5234BCCKIT. 

The DP83640 is the newest addition to the PHYTER family, which also includes the DP83848 commercial, industrial and extreme-environment transceivers, and the DP83849, the industry's first dual-port transceivers with flex-port switching and advanced cable diagnostics.

With a broad range of high-performance, low-power industrial connectivity products, the PHYTER family offers enhanced performance and reliability in a range of temperature ranges to meet the requirements of harsh operating environments.

Key technical features and benefits

The DP83640 transceiver supports both versions 1 and 2 of the IEEE 1588 PTP specification.  For ease of implementation, the standard register interface used for data transmission and control of the PHY operation also provides control of the IEEE 1588 PTP features. A platform- independent “C” software library is available to simply integration by eliminating the need to interact directly with the device registers.

For increased precision and phase accuracy, the DP83640 offers a unique 100 Mb synchronous Ethernet mode that eliminates any inaccuracy caused by clock drift between nodes. The DP83640 also supports 100Base-FX and includes a signal detect pin that allows selection of a wide variety of fiber transceivers.
 
A powerful cable diagnostic tool is included that features dynamic link quality monitoring, signal-to-noise ratio (SNR) estimation and time domain reflectometry (TDR).  The dynamic link quality monitor developed by National Semiconductor allows designers to implement a fault- prediction mechanism that detects changing or deteriorating link conditions and proactively takes corrective action, saving lengthy system downtime and costly repairs.

Complete synchronised signal path portfolio National designs its high-performance analogue products, such as National’s new operational amplifiers, analogue-to-digital converters (ADCs) and PHYTER transceivers to ensure the fidelity of the signal path, resulting in improved system performance.

For example, the DP83640 can be designed with the new LMP7731 and LMP7732 precision operational amplifiers, as well as the recently released ADC121S655 ADC, to create a low-power, cost-effective high-resolution data acquisition system.

Contact information

For further information, contact National Semiconductor European Customer Support Centre on +44 (0) 870 240 2171.