Short-range communications is one of the most relevant as well as diversified fields of en-
deavour in wireless communications. As such, it has been a subject of intense research and
development worldwide, particularly in the last decade. There is no reason to believe that this
trend will decline. On the contrary, the rapidly crystallizing vision of a hyper-connected world
will certainly strengthen the role of short-range communications in the future. Concepts such
as wireless social networks, Internet of things, car communications, home and office network-
ing, wireless grids and personal communications heavily rely on short-range communications
technology.
Developers, manufacturers and marketers of products incorporating short-
range radio systems are experts in their fields—security, telemetry,
medical care, to name a few. Often they add a wireless interface just to
eliminate wires on an existing wired product. They may adapt a wireless
subsystem, which is easy to integrate electrically into their system, only to
find that the range is far short of what they expected, there are frequent
false alarms, or it doesn’t work at all. It is for these adapters of wireless
subsystems that this book is primarily intended.
FEATURES
Unique 1-Wire interface requires only one port pin for communication
Multidrop capability simplifies distributed temperature sensing applications
Requires no external components
Can be powered from data line. Power supply range is 3.0V to 5.5V
Zero standby power required
Measures temperatures from -55°C to +125°C. Fahrenheit equivalent is -67°F to +257°F
±0.5°C accuracy from -10°C to +85°C
Thermometer resolution is programmable from 9 to 12 bits
Converts 12-bit temperature to digital word in 750 ms (max.)
User-definable, nonvolatile temperature alarm settings
Alarm search command identifies and addresses devices whose temperature is outside of programmed limits (temperature
alarm condition)
Applications include thermostatic controls, industrial systems, consumer products,
thermometers, or any thermally sensitive system
This document was developed under the Standard Hardware and Reliability Program (SHARP) TechnologyIndependent Representation of Electronic Products (TIREP) project. It is intended for use by VHSIC HardwareDescription Language (VHDL) design engineers and is offered as guidance for the development of VHDL modelswhich are compliant with the VHDL Data Item Description (DID DI-EGDS-80811) and which can be providedto manufacturing engineering personnel for the development of production data and the subsequent productionof hardware. Most VHDL modeling performed to date has been concentrated at either the component level orat the conceptual system level. The assembly and sub-assembly levels have been largely disregarded. Under theSHARP TIREP project, an attempt has been made to help close this gap. The TIREP models are based upon lowcomplexity Standard Electronic Modules (SEM) of the format A configuration. Although these modules are quitesimple, it is felt that the lessons learned offer guidance which can readily be applied to a wide range of assemblytypes and complexities.
Industrial systems demand semiconductors that are precise, flexibleand reliable. Linear Technology offers a broad line of high performanceanalog ICs that simplify system design with rugged devices featuringparameters fully guaranteed over the -40°C to 85°C temperature range.We back this up with knowledgeable applications support, long productlife cycles and superior on-time delivery.
The MAX5713/MAX5714/MAX5715 4-channel, low-power,8-/10-/12-bit, voltage-output digital-to-analog converters(DACs) include output buffers and an internal referencethat is selectable to be 2.048V, 2.500V, or 4.096V. TheMAX5713/MAX5714/MAX5715 accept a wide supplyvoltage range of 2.7V to 5.5V with extremely low power(3mW) consumption to accommodate most low-voltageapplications. A precision external reference input allowsrail-to-rail operation and presents a 100kI (typ) load toan external reference.
Abstract: A perfect voltage reference produces a stable voltage independent of any external factors. Real-world voltagereferences, of course, are subject to errors caused by many external factors. One causeof these major errors istemperature. Without care, it is easy to operate a voltage reference outside its operating temperature range. Thisapplication note describes how references respond to temperature changes, and how self-heating can cause a voltagereference to operate outside its recommended temperature range. Once understood, this knowledge can then be used toavoid making this design error.
Abstract: A laser module designer can use a fixed resistor, mechanical pot, digital pot, or a digital-to-analogconverter (DAC) to control the laser driver's modulation and bias currents. The advantages of a programmablemethod (POT or DAC) are that the manufacturing process can be automated and digital control can be applied(e.g., to compensate for temperature). Using POTs can be a more simple approach than a DAC. There can be aslight cost advantage to using a POT, but this is usually not significant relative to other pieces of the design.Using a DAC can offer advantages, including improved linearity (translating to ease of software implementationand ability to hit the required accuracy), increased board density, a wider range of resolutions, a betteroptimization range, ease of use with a negative voltage laser driver, and unit-to-unit consistency
The purpose of this application note is to show an example of how a digital potentiometer can be used in thefeedback loop of a step-up DC-DC converter to provide calibration and/or adjustment of the output voltage.The example circuit uses a MAX5025 step-up DC-DC converter (capable of generating up to 36V,120mWmax) in conjunction with a DS1845, 256 position, NV digital potentiometer. For this example, the desiredoutput voltage is 32V, which is generated from an input supply of 5V. The output voltage can be adjusted in35mV increments (near 32V) and span a range wide enough to account for resistance, potentiometer and DCDCconverter tolerances (27.6V to 36.7V).
