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Motor drive ICs
Gigahertz GaAs ICs on silicon Silicon-based packaging for gigahertz GaAs integrated circuits (ICs) has been developed by US firm GigaBit Logic. The technique allows operation to 4 GHz clock rates or 100 ps signal rise and fall times, according to GigaBit's director of packaging and test, Tushar Gheewala. In this packaging approach, the GaAs IC is piggybacked on a silicon chip. The silicon chip is mounted inside a flatpack or leadless chip carrier package. Short wirebonds connect the GaAs IC to the silicon chip and the silicon chip to the package. At gigahertz speeds, power supply decoupling capacitors have to be placed very close to the GaAs die to suppress switching transient disturbances on the supplies, explains GigaBit. Longwirebonds and external decoupling capacitors in traditional packaging are ineffective at high
speeds because the interconnect inductances prevent the capacitor from being seen as a lowimpedance ground. So the GigaBit technique puts the power supply decoupling capacitors right next to the GaAs IC. The technique is also intended to provide proper impedance matching for input and output signals. The silicon chip provides terminating resistors for input signals and shielded coplanar microstrip transmission lines. The purpose of these is to minimize reflections and crosstalk respectively. The silicon, having a higher thermal conductivity than ceramic, should also improve the heat dissipation of the package. (GigaBit Logic, 1908 Oak Terrace Lane, Newbury Park, CA 91320, USA. Tel: (805) 498 9664)
OG~O. iSOLATOR f~ V O L T ON[ Y
5 V O L T ON~ Y
68010 on VME card 68010-based CPUs on standard double-size VME cards have been introduced by US firm Integrated Solutions. The VME-68k10 provides dual memory and I/O bus architecture, up to 64 kbyte of EPROM or ROM and upto 16 kbyte of static RAM. Either a 10 MHz or a 12 MHz 68000/68010 CPU is incorporated on the card. The VME-68k10 contains a programmable interrupt timer, two serial ports and a memory management unit. By adding one or more VMEHSMEM dual-ported memory cards, says UK distributor Unit-C, the processor can gain access to the full 16 Mbyte of physical memory present on the VMEbus, without a wait state. Power requirements for the CPU unit are 5 V or 12 V. The operating temperature range is 0-50°C. (Integrated Solutions Inc., 2240 Lundy Avenue, San Jose, CA 95131, USA. UK distributor: Unit-C Ltd, Dominion Way West, Broadwater, Worthing, Sussex BN14 8NT, UK. Tel: (0903) 205233)
Motor drive ICs
tSOL A ~ I O N
An octal bidirectional active data bus isolator has been produced for use with 8-bit microprocessor data buses. The NM1608 device operates from 5 V and has standard HCMOS inputs and outputs for all data lines, says the maker Newport Components of the UK. Direction and enable inputs can be driven from either side of the isolator. In many applications, adds Newport, a single NM1608 can give an enhanced-performance alternative to 16 high-speed optocouplers with buffering. (Newport Components Ltd, 134 Tanners Drive, Blakelands North, Milton Keynes MK14 5BP, UK. Tel. (0908) 615232. Telex: 825621 NUPORT)
vol 9 no 2 march 1985
Italian firm SGS has introduced two dual-bridge integrated circuits tiCs) for driving DC and stepper motors. The L6208 integrates two 2 A-24 V H-bridge power stages plus predriver circuitry allowing direct connection to low-voltage logic. The L298 is functionally equivalent, says SGS, but is for use with a higher motor supply voltage. The L6208 is controlled by six logic inputs: a control input for each half-bridge plus an enable input for each bridge. One L6208 can drive two bidirectional DC motors or both phases of a two-phase bipolar stepper motor. The IC comes in a vertical version, and in a horizontal Multiwatt-15H version for applications where height is limited (eg floppy disc drives). (SGS, Via C Olivetti 2, 20041 Agrate Brianza, Italy. Tel: (39) 39 655 54 21. Telex: 43 330 131)
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speeds because the interconnect inductances prevent the capacitor from being seen as a lowimpedance ground. So the GigaBit technique puts the power supply decoupling capacitors right next to the GaAs IC. The technique is also intended to provide proper impedance matching for input and output signals. The silicon chip provides terminating resistors for input signals and shielded coplanar microstrip transmission lines. The purpose of these is to minimize reflections and crosstalk respectively. The silicon, having a higher thermal conductivity than ceramic, should also improve the heat dissipation of the package. (GigaBit Logic, 1908 Oak Terrace Lane, Newbury Park, CA 91320, USA. Tel: (805) 498 9664)
OG~O. iSOLATOR f~ V O L T ON[ Y
5 V O L T ON~ Y
68010 on VME card 68010-based CPUs on standard double-size VME cards have been introduced by US firm Integrated Solutions. The VME-68k10 provides dual memory and I/O bus architecture, up to 64 kbyte of EPROM or ROM and upto 16 kbyte of static RAM. Either a 10 MHz or a 12 MHz 68000/68010 CPU is incorporated on the card. The VME-68k10 contains a programmable interrupt timer, two serial ports and a memory management unit. By adding one or more VMEHSMEM dual-ported memory cards, says UK distributor Unit-C, the processor can gain access to the full 16 Mbyte of physical memory present on the VMEbus, without a wait state. Power requirements for the CPU unit are 5 V or 12 V. The operating temperature range is 0-50°C. (Integrated Solutions Inc., 2240 Lundy Avenue, San Jose, CA 95131, USA. UK distributor: Unit-C Ltd, Dominion Way West, Broadwater, Worthing, Sussex BN14 8NT, UK. Tel: (0903) 205233)
Motor drive ICs
tSOL A ~ I O N
An octal bidirectional active data bus isolator has been produced for use with 8-bit microprocessor data buses. The NM1608 device operates from 5 V and has standard HCMOS inputs and outputs for all data lines, says the maker Newport Components of the UK. Direction and enable inputs can be driven from either side of the isolator. In many applications, adds Newport, a single NM1608 can give an enhanced-performance alternative to 16 high-speed optocouplers with buffering. (Newport Components Ltd, 134 Tanners Drive, Blakelands North, Milton Keynes MK14 5BP, UK. Tel. (0908) 615232. Telex: 825621 NUPORT)
vol 9 no 2 march 1985
Italian firm SGS has introduced two dual-bridge integrated circuits tiCs) for driving DC and stepper motors. The L6208 integrates two 2 A-24 V H-bridge power stages plus predriver circuitry allowing direct connection to low-voltage logic. The L298 is functionally equivalent, says SGS, but is for use with a higher motor supply voltage. The L6208 is controlled by six logic inputs: a control input for each half-bridge plus an enable input for each bridge. One L6208 can drive two bidirectional DC motors or both phases of a two-phase bipolar stepper motor. The IC comes in a vertical version, and in a horizontal Multiwatt-15H version for applications where height is limited (eg floppy disc drives). (SGS, Via C Olivetti 2, 20041 Agrate Brianza, Italy. Tel: (39) 39 655 54 21. Telex: 43 330 131)
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