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PRODUCT SHOWCASE Fast-charge battery controller Philips has released a single-chip fast-charge controller, the TEA1102, which is able to cope with all battery types including nickel cadmium (NiCd), nickel metal hydride (NiMH), lithium ion and sealed lead-acid (SLA) batteries. The TEA1102 uses DT/dt (rate of change of battery tempera­ ture) and peak voltage detection modes to ensure that the full charge condition is reliably detected in NiCd and NiMH battery packs. To enhance the reliability of the DT/dt and peak voltage detection, both detectors are temporarily disabled for a short time at the beginning of the fast charge period and the DT/dt detector is itself temperature compensated. The detection modes can be selected individually or used together. Even if only the DT/dt detection is selected, the TEA1102 will automatically switch over to peak voltage detection if the battery pack’s temperature sensing thermistor fails, thereby ensuring maximum safety. The TEA1102 has linear and PWM outputs to control current regulator transistors and the fast-charge current can be pro­grammed to values between half and five times the battery’s nom- Light pipes for LEDs The Khatod SMT Pipe Light enables surface mounted LEDs on a PC board to illuminate front panel indicators by providing a 90 degree light path. Special shapes and symbols can be provided and the Pipe Light has electrostatic discharge protection of 15kV. They can be used with conventional LEDs of 3mm or 5mm diameter and can be ordered with or without LEDs. Pipe Light is available in red, green and yellow and can operate 86  Silicon Chip inal ampere capacity. Single cell or multiple cell battery packs can be charged. If the charger is built into equipment which must remain operational while its battery pack is removed, the TEA1102 can operate as an AC/DC adapter, delivering a regulated voltage output rather than a pulsed charging current. Charging lithium ion and SLA batteries is completely dif­ferent. When the batteries reach their maximum voltage (adjust­able), the TEA1102 automatically switches over from current regulation to voltage regulation. After a defined period, which is dependent on battery capacity and charging current, charging is terminated; trickle charging is not necessary. Other features include manually activated discharge (“re­ f resh”) of NiCd batteries before recharging to overcome “memory” effect, minimum and maximum temperature protection, short circuit and time-out protection and outputs for LEDs and a buzzer to indicate charging conditions. The TEA1102 is available in 20-pin DIP or SO packages. For further information, contact Philips Components, 34 Waterloo Rd, North Ryde, NSW 2213. Phone (02) 9805 4479; fax 9805 4466. Voice echo canceller within a temperature range of -60 to 125°C. For further information contact M. Rutty & Co, 4 Beaumont Rd, Mt Kuringai, NSW 2080. Phone (02) 9457 2222. Mitel Semiconductor is now sampling an integrated voice echo canceller designed to eliminate voice echo and distortion. The MT9122 is a dual- channel VEC that accepts 16bit linear or G.711 companded PCM formats and is compatible with the ST-Bus and SSI. Power consumption is typically 250mW. It is also claimed to eliminate distortion without the need to add separate DSPs for other functions. Applications include wireless base AUDIO TRANSFORMERS High output infrared LEDs Allthings Sales and Services has released three new LEDs which are suitable for high output video camera IR illuminators, IR remote control and IR communication (IrDA PC) links. Main parameters are: up to 52mW/steradian (continuous) radi­ant intensity, radiation angles from 24-60°, spectral radiation wavelength from 800-950nm and standard 5mm dia­meter transparent (clear) packages. All are suitable for CCD video camera infrared illuminators. A 925-950nm device has a continu- stations, video confer­encing and central office switches. Echo cancellation works by measuring the echo endpath and then using an adaptive filter to generate a duplicate echo which is then subtracted from the original echo. As the echo tail length increases, distortion begins to create the familiar hollow sound in a receiver and eventually distinct echoes emerge. For further information, contact GEC Electronics Division, Unit 1, 38 South St, Rydalmere, NSW 2116. Phone (02) 9638 1888; fax (02) 9638 1798. Handy SMD replacement kit PRB has released the CQ-1000 SMD replacement kit. This has the tools and materials to remove SMCs, clean the ous radiant intensity of 50mW/sr <at> 100mA and for remote control or IR links up to 500mW/sr when pulsed at 1A. For IR illuminators, radiation angles of 24, 50 and 60 degrees allow close matching of the video camera lens field of view with the illuminator radiation angle, regardless of whether it is mounted behind, next to or ahead of the camera. In packets of 50, they are priced between 50 and 70 cents each. Full technical specifications and data are available from Allthings Sales and Services, PO Box 25, Westminster, WA 6061. Phone (09) 9349 9413; (09) 9344 5905. Manufactured in Australia Comprehensive data available Harbuch Electronics Pty Ltd 9/40 Leighton Pl. HORNSBY 2077 Ph (02) 9476-5854 Fx (02) 9476-3231 BassBox® Design low frequency loudspeaker enclos­ures fast and accurately with BassBox® software. Uses both Thiele-Small and Electro-Mechanical parameters with equal ease. Includes X. Over 2.03 passive cross­over design program. $299.00 Plus $6.00 postage. Pay by cheque, Bankcard, Mastercard Visacard. EARTHQUAKE AUDIO PH: (02) 9949 8071 FAX: (02) 9949 8073 PO BOX 226 BALGOWLAH NSW 2093 This paste does not require refrigerated storage, making the CQ-1000 kit suitable for carrying in a serv­ice tool case, for the occasional field repair. For further information, contact Computronics International Pty Ltd, 31 Kensington St, East Perth, WA 6004. Phone (09) 221 2121; fax (09) 325 6686. Quad low side driver IC board and replace the component. The only other tool required is a tempera­ ture controlled soldering iron. The kit contains enough material to remove approximately 2500 SMD pins plus dental picks, vacuum pick-up tools and a new no-clean solder paste. SGS-Thomson Microelectronics has released the L9338 quad low side driver IC. It contains four driver channels, each equipped with a logic input and an open-drain DMOS output tran­ sistor with an on-resistance of 1.5Ω at 25°C and an output clamp for fast March 1997  87 recirculation with inductive loads. The switching speed is controlled to minimise electromag­netic interference and over-temperature protection is provided. A diagnostic output indicates the status of the protection function and open load conditions. The outputs default to a defined state in case of open circuit inputs. In stand-by mode, the L9338 consumes less than 2µA. It oper­ates on a supply voltage from 4.5V to 45V and is reverse bias protected to -24V. The circuit is supplied in an SO-20 surface mounting package. Typical automotive applications include relay and lamp driving. Industrial applications include driving relays in pro­grammable controllers or as a line driver. For further information phone (02) 9580 3811; (02) fax 9580 6440. TP-79 lead cutting machine Computronics Corporation Ltd has released the TP-79 lead cutting machine for radial components. The TP-79 features a gear driven cutting wheel which has a scissors action on KITS-R-US RF Products FMTX1 Kit $49 Single transistor 2.5 Watt Tx free running 12v-24V DC. FM band 88-108MHz. 500mV RMS audio sensitivity. FMTX2A Kit $49 A digital stereo coder using discrete components. XTAL locked subcarrier. Compatible with all our transmitters. FMTX2B Kit $49 3 stage XTAL locked 100MHz FM band 30mW output. Aust pre-emphasis. Quality specs. Optional 50mW upgrade $5. FMTX5 Kit $98 Both a FMTX2A & FMTX2B on 1 PCB. Pwt & audio routed. FME500 Kit $499 Broadcast specs. PLL 0.5 to 1 watt output narrowcast TX kit. Frequency set with Dip Switch. 220 Linear Amp Kit $499 2-15 watt output linear amp for FM band 50mW input. Simple design uses hybrid. SG1 Kit $399 Broadcast quality FM stereo coder. Uses op amps with selectable pre-emphasis. Other linear amps and kits available for broadcasters. 88  Silicon Chip For more information, contact Computronics Corporation Ltd, 31 Kensington Street, East Perth, WA, 6004. Phone (09) 9221 2121; fax (09) 9325 6686. 20MHz function generator the component leg, giving a clean cut, longer blade life and ease of use. It is capable of a production rate of 50,000 per hour. The lead length is adjustable from 2mm to 10mm and the blade can accommodate lead diameters from 0.3mm to 1.2mm. Adjust­ment is made by using the integrated lead length ruler marked below the moving wheels. A toothed drum ensures the leads are parallel during the cutting process, providing correct lead configuration for inser­tion of the component into the PC board. Adjustment tools, bandolier holder and a full size metal collection tray are included with the TP-79. PO Box 314 Blackwood SA 5051 Ph 0414 323099 Fax 088 270 3175 AWA FM721 FM-Tx board $19 Modify them as a 1 watt op Narrowcast Tx. Lots of good RF bits on PCB. The new Thurlby Thandar TG120 function generator has a frequency range of 0.2Hz to 20MHz over eight ranges. It can be used in sweep mode (with an external sweep source) with a sweep range of at least 20:1. Outputs include sine, triangle, square wave and DC level waveforms, as well as variable duty cycle and sawtooth pulses. The instrument has a main output of 20V peak-peak, from a 50Ω source impedance. A two-step attenuator (20dB/step) and a 26dB vernier provide levels down to 10mV peak-peak. A variable DC offset of ±10V can also be provided. For more information, contact Nilsen Technologies, 150 Oxford St, Collingwood, Vic 306. Phone 1 800 623 350; fax 1 800 067 263. 20MHz oscilloscope from Leader Instruments AWA FM721 FM-Rx board $10 The complementary receiver for the above Tx. Full circuits provided for Rx or Tx. Xtals have been disabled. MAX Kit for PCs $169 Talk to the real world from a PC. 7 relays, ADC, DAC 8 TTL inputs & stepper driver with sample basic programs. ETI 1623 kit for PCs $69 24 lines as inputs or outputs DS-PTH-PCB and all parts. Easy to build, low cost. ETI DIGI-200 Watt Amp Kit $39 200W/2 125W/4 70W/8 from ±33 volt supply. 27,000 built since 1987. Easy to build. ROLA Digital Audio Software Call for full information about our range of digital cart players & multitrack recorders. ALL POSTAGE $6.80 Per Order FREE Steam Boat For every order over $100 re­ceive FREE a PUTT-PUTT steam boat kit. Available separately for $19.95, this is one of the greatest educational toys ever sold. Leader Instruments has released a 20MHz oscilloscope for under $800 including sales tax. It features a maximum sensitivity of 500µV/div for measuring low level signals, and a maximum sweep speed of 50ns/div. A worthwhile feature is the inclusion of a buffered channel 1 output which can be used for connecting a frequency counter. Other features include variable holdoff, TV triggering and the usual operation modes of CH1, CH2, CHOP, ALT and ADD. For further information, contact Stantron Australia, Suite 1, Unit 27, 7 Anella Ave, Castle Hill, NSW 2154. Phone (02) 9894 2377; fax (02) 9894 2386.