Circuit Protection, Isolation and Interconnect Devices Intro’d at Electronica 2012

During Electronica 2012, TE Circuit Protection and Littelfuse both targeted energy-efficient ac-input applications such as LED lighting with advanced circuit protection solutions. Avago Technologies added a wider offering of extended temperature range digital optocouplers to the existing family. The new devices are designed to meet customer needs for low power, low leakage, higher isolation voltage and higher common-mode rejection (CMR). Harwin introduced a new high-reliability connector family based on a 1.25mm pitch.

TE Circuit Protection introduced the 2Pro AC device, an innovative hybrid device that offers designers an integrated, resettable approach to protect sensitive downstream electronics against damage from overcurrent and overvoltage events. This new device combines a PPTC (polymeric positive temperature coefficient) device and a thermally enhanced MOV (metal-oxide varistor) into one package. As a result, it provides higher reliability, reduced component count and a faster, simpler design process compared to other ac-line protection solutions typically used in low-current applications such as LED lighting, smart meters, appliances and power supplies.

By integrating a resettable PPTC device with an MOV, the innovative hybrid configuration of the 2Pro AC device offers benefits over typical approaches currently used in low-current applications to help prevent thermal runaway. These include using an MOV with a fuse, which must be replaced when blown; placing the PPTC device and MOV next to each other on the board, which can lead to thermal instability and design complexity; or employing a thermal fuse integrated with an MOV, which is a one-use solution that trips without allowing resettability. In contrast, the 2Pro AC device has thermally coupled components, is resettable, and provides stability by maintaining a varistor surface temperature of less than 150°C.

�¢ï¿½ï¿½Popular energy-efficient applications, like LED lighting, are vulnerable to potentially damaging surges caused by "dirty" power and lightning," said Weiqing Guo, TE Circuit Protection's Global Product Manager. "The 2Pro AC device responds to this challenge by offering a PPTC/MOV hybrid device that provides a more reliable, easy-to-use, space-saving protection solution over existing discrete approaches."

During the Electronica fair, Bharat Shenoy Director of Technical Marketing at Littelfuse spoke about the "Safety and Surge Immunity Requirements for Indoor and Outdoor LED Lighting Applications". His presentation attracted the attention of electrical manufacturers who were interested in hearing about the latest international circuit protection standards and developments for the LED industry.

"Product designers are switching to LEDs for lighting because of their low cost, high performance, minimum maintenance, and the fact that they can theoretically last forever," noted Shenoy. "However, as LEDs enter harsh environments outside of their traditional role circuit protection becomes critically important, stretching from the input power supply to individual LEDs. Hence, one of our key messages here today is about integrating protection in the product design."

Avago Technologies announced its ACPL-M49U/K49U/M71U/M72U digital optocouplers, which are new additions to its R2Coupler™ family. These optocouplers provide a wider offering of extended temperature range digital optocouplers to the existing family and are designed to meet customer needs for low power, low leakage, higher isolation voltage and higher common-mode rejection (CMR).

Avago Technologies' extended operating temperature digital optocouplers are increasingly used in a wide variety of isolation applications ranging from power supply, computing, factory automation, data communications and digital logic interface circuits.

These new digital optocouplers, ACPL-M49U/K49U/M71U/M72U ensure the AC and DC performances over the extended temperature range of -40 degrees C to +125 degrees C. The ACPL-M71U/M72U devices are high speed, low power digital optocouplers with R2Coupler(TM) isolation and a low power consumption of 1.5mA. The ACPL-M71U uses a high-speed LED to achieve 35ns maximum propagation delay, while the ACPL-M72U uses a low current LED for lower power consumption. The ACPL-M49U/K49U are low speed, high CMR digital optocouplers, both configurable as low power and low leakage optocouplers. An internal shield also ensures a CMR of typical 30 kV/us at 1500V common-mode voltage.

The ACPL-M49U and ACPL-K49U are immediately available in sample quantities, and will sell for $1.13 apiece and $1.25 apiece in lots of 10k units respectively. The ACPL-M71U and ACPL-M72U are immediately available in sample quantities, and will sell for $1.75 apiece in lots of 10k units.

Harwin introduced a new high-reliability connector family based on a 1.25mm pitch. Named Gecko, the new connectors have benefited from Harwin's exceptional track record of manufacturing high-reliability connectors for safety-critical applications.

Harwin's low profile G125 series connectors are designed to offer high performance in a miniature package. The 1.25mm pin spacing results in a 35% space saving over other high-performance connectors such as Micro-D. The connectors are rated to handle 2A per contact. Tested and proven to allow high performance in extreme conditions, the G125 family can operate within a wide temperature range (-65 to +150°C) and under extreme vibration (Z axis 100g 6m/s). This high performance is made possible by Harwin's four-finger patented Copper Alloy contact.

Offering up to 50 contacts per connector and available in dual row cable-to-board and board-to-board configurations, Gecko family connectors include a wealth of features including polarization points that prevent miss-mating, easy identification of the No 1 position for fast visual inspection and optional latches that allow simple and fast de-latching that requires no special tooling. Cable connectors feature a rear potting wall adding an extra level of strain relief

Andrew McQuilken, Harwin's CEO observed, "There are millions of our Datamate connectors being used today in harsh environment applications. We have incorporated all the features that we have developed over the years thanks to user feedback on that 2mm connectors series within the new Gecko 1.25mm pitch products, so we can confidently expect a wide market uptake in applications including; UAVs and Aerospace, medical, motor sport, robotics, defense, oil and gas exploration and instrumentation -- in fact anywhere where performance and safety is paramount."