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pulseContact system is first activeimplantable medical deviceDesigners of implantablemedical-electronicdevices for cardiac-rhythmmanagement,neuromodulation, and neurostimulationtherapies needways to connect to thosedevices. Connection mustoften occur in a surgical environment,and it’s thus importantto minimize the time asurgeon needs to make theconnections. Addressing thisneed, Bal Seal EngineeringInc, a provider of customengineeredsealing, connecting,and conducting products,has announced plansto launch what it claims isthe fi rst integrated seal andelectrical-contact system foractive implantable devices.The new contact system canestablish multiple contactswith a single setscrew holdingthe contacts in place.DILBERT By Scott AdamsThe company will formallylaunch the Sygnus implantablecontact system nextmonth at the Medical Designand Manufacturing show inMinneapolis. Sygnus combineselectrical contacts and isolationseals in a standardized, platform-readystack confi guration.Bal Seal is launching an integrated seal and electrical-contact systemfor active implantable devices. The system can establish multiplecontacts with a single setscrew holding the contacts in place.The system pairs the company’sBal Conn electrical-contacttechnology with pretested siliconeseals, resulting in a packagethat helps medical-deviceOEMs improve speed to marketand eliminate the need forprocurement and testing of individualcomponents.“The upcoming launch ofSygnus is our direct responseto the medical-device community’sdemand for an integratedsealing and connecting systemthat incorporates an established,ultrareliable contact ina plug-and-play platform thatdoesn’t compromise performance,”says Mark Russell, BalSeal’s global medical-electronicsaccount manager. Accordingto Russell, Sygnus builds ontechnology that’s at work inmore than a million implantabledevices worldwide.The number of contacts andseals in the Sygnus system willbe confi gurable to meet applicationand industry requirements,such as the IS4 standardfor cardiac-health-managementdevices. The company’strademarked Canted-coilspring-contact design offersmultipoint conductivity and lowinsertion force, and it compensatesfor any surface irregularity.The system comprises a seriesof electrical contacts, includingplatinum-iridium Canted-coilsprings in metal housings madefrom MP35N, and implantablegradesilicone seals, which providedielectric isolation. Thecombined stack is resistant tolong-term material adhesionand potential fatigue due tomultiple lead-insertion cycles.The company plans to subjectthe stack and package contactsto force and resistancetests and to package the sealingcomponents to comply withcritical standards for “clean”packaging.—by Rick Nelson▷Bal Seal, http://balseal.com.SUPERCAPACITORCHARGERS TOUTAUTOMATIC CELLBALANCINGLinear Technology’s newLTC3625 and LTC3625-1two-cell supercapacitorchargers address highpeak-power,data-backup,and “dying-gasp” needsin portable-system anddata-storage applications.The devices’ switch-modetopology includes aninternal buck converterbetween the input voltageand the series capacitor’smidpoint voltage to regulatethe voltage on thebottom capacitor. It alsoincludes an internal boostconverter between themidpoint voltage and theoutput voltage to regulatethe voltage across the topcapacitor.The devices can chargetwo supercapacitors inseries from a 2.7 to 5.5Vcurrent-limited supply to apin-selectable output voltageof 4.8 or 5.3V for theLTC3625 and 4 or 4.5V forthe LTC3625-1. They alsofeature automatic cellbalancing,which maintainsapproximately equalvoltages across both cells,eliminating the need forbalancing resistors.Other features includeovertemperature andreverse-current protectionand overcurrentlimiting. The LTC3625and LTC3625-1 come in3×4-mm DFN packagesand operate over −40 to+125°C. Prices start at$3 and $3.45 for E- andI-grade versions.—by Fran Granville▸Linear Technology Corp,www.linear.com/3625.09.09.1014 EDN | SEPTEMBER 9, 2010