Electronics News
Archive : 12 February 2008 год
Vishay announces the Z202 series of miniature ultra-high-precision Z-Foil resistors, which provide a typical TCR of ±0.05ppm/°C from 0°C to +60°C, PCR (ΔR due to self heating) of ±5ppm at rated power, tolerances to ±0.01%, load life stability of ±0.01%, and can be trimmed to any specific value at any tolerance within the standard resistance range of 5Ω to 30kΩ. The Z202 is a miniaturized version of Vishay’s Z201. Constructed with a Bulk Metal Z-Foil element, it provides all of the inherent performance benefits of Z-Foil resistors. Vishay’s Z-Foil technology reduces the resistive component’s sensitivity to ambient temperature variations and applied power changes. This breakthrough level of stability, more than an order of magnitude better than that offered by other resistor technologies such as thin film, wirewound, and thick film, allows designers to guarantee a high degree of accuracy in fixed-resistor applications.
Applications for the new Z202 series include precision amplifiers, high-precision instrumentation, medical and automatic test equipment, high-end stereo equipment, electron beam scanning and recording equipment, and military, aerospace, and down-hole equipment and instrumentation. The Z202 devices have a load-life stability of ±0.01% for 2000 hours at 70°C; a power rating of 0.125W at +125°C (0.25W at +70°C); current noise of < -40dB; and thermal EMF of 0.1μV/°C. They offer a non-inductive (<0.08μH), non-capacitive design, feature a voltage coefficient of <0.1ppm/V, and provide ESD protection above 25000V. The Z202 is available with both RoHS-compliant, lead (Pb)- free terminations and tin/lead terminations. Matched sets are also available upon request.
Micronas announced its easyLIN product line of 8-bit microcontrollers for LIN bus applications. Today's cars and trucks have multiple LIN bus modules connecting smart sensors and controlling smart actuators used in power windows, wipers, and many other functions. The HVC 22xyA and HVC 24xyA simplify the design and reduce the cost of LIN bus modules by combining all logic functions, peripheral modules, interfaces and a LIN bus interface in a single device. The family devices integrate 5V and 2.5V regulators, true EEPROM, watchdogs and power-driver electronics. The included internal voltage regulators operate directly from an automobile's 12-volt supply and withstand load dumps of up to 40 volts, a requirement in vehicle applications. easyLIN also contains a switchable 5-volt supply output, which can be used to power external subsystems.
Complementing the high-voltage-tolerant regulators, the family can directly drive up to eight 12-volt loads, such as lamps and relays. Relay driver protection is also embedded. The on-chip transistors resist moderate loads, and can drive external power transistors for large loads. These drivers include three fast-shutdown modules for power MOSFET transistor protection that respond virtually on the instant, without CPU involvement. Working with on-chip pulse-width modulators (PWM), easyLIN can also drive brushed and brushless DC motors. Combining all these features with a sophisticated 8051-type 8-bit CPU core and a full range of peripherals, the easyLIN family is typically the only component needed for a LIN bus slave application.
The easyLIN is a complete digital subsystem: It has a full LIN 2.0 physical layer interface, a fast 10-bit queued ADC (analog-to-digital converter), three multithreshold comparators, an op-amp, and multiple interrupt inputs. It is available in Flash and ROM versions, both types include true EEPROM. Other integrated peripherals include two 8-bit and two 16-bit timers, an SPI interface, a 16-bit PWM and three enhanced 12-bit PWMs. In addition, the easyLIN contains its own supervisory circuit. An on-chip temperature sensor against an overheat condition, and a supply monitor resets the device if the power supply goes out of range, even momentarily. All easyLIN family devices operate from -40 to +125 °C, necessary in the harsh environment of automotive electronics. The family offers a range of power-saving modes, with current consumption as low as 20 µA while still preserving RAM data.
Micronas supplies a number of development tools. For hardware development, application/evaluation boards and JTAG/Trace probes are available. For software development, a full range of tools from third-party vendors are offered. Micronas supplies an API (Application Programming Interface) with support for all peripherals. Fast-turn development is supported by contact-ROM technology for quick turns and a patch module for in-the-field changes of code or data in ROM. The device is offered in a PSOIC28 package. Pricing varies with the exact model, but ranges from 1.60 to 2.20 Euro for low quantities.
Source: www.channel-e.biz
STMicroelectronics announced devices that combine EMI filtering and ESD protection in a single package, enabling system designers to implement both functions within a footprint of 0.6mm2. Two devices have been announced, meeting IEC61000-4-2 level 4 for ESD protection and also having line-to-ground capacitance of 30pF to preserve high-speed signal integrity. Filter characteristics include high attenuation in the GSM band, enabling enhanced performance when protecting the keypad, side keys, external connectors or data lines in smart phones, PDAs, portable computers, PC peripherals and M2M communication modules.
The smallest component introduced is the EMIF01-1003M3 for single-line applications. It is housed in a 0.6mm-high SOT883 package with a 1.0 x 0.6mm footprint. The EMIF02-1003M6 is a two-channel device in a 1.0 x 1.45mm Micro QFN 6-lead package. Both devices achieve 15kV air discharge and 8kV contact discharge, in accordance with the IEC61000-4-2 specification. Clamping performance is also robust thanks to the internal Pi-protection structure, with 9V clamping voltage for the EMIF01 and 17V for the EMIF02, when subjected to a 15kV ESD strike.
A series resistance of 100 Ohms and leakage current of 100nA minimizes energy losses during normal circuit operation. The EMIF01-1003M3 and EMIF02-1003M6 are available now, in units of 100,000 upwards, at a price of $0.09 and $0.15, respectively.