Abstract: There are differences between the operation of low-frequency AC transformers and electronic transformersthat supply current to MR16 lamps, and there are also differences in the current draw for MR16 halogen lamps andMR16 LED lamps. These contrasts typically prevent an MR16 LED lamp from operating with most electronictransformers. This article explains how a high-brightness (HB) LED driver optimized for MR16 lamps will allow LEDlamps to be compatible with most electronic transformers.A similar version of this article appeared on Display Plus, July 7, 2012 and in German in Elektronikpraxis, October 1,2012.
Abstract: We don't expect manufacturers to produce clothes that in one size that fits everyone. In thesame way, one ESD component can't solve all issues—each application has different ESD requirements.Knowing that "one size fits all" cannot apply to power design, the power designer, or the engineering"super hero," must consider all the potential disruptions to a steady flow of power and thenvarious waysto mitigate them. This tutorial describes voltage- and current-limiting devices and risetime reducers tomanage the power. It also points to free and low-cost software tools to help design lowpass filters, checkcapacitor self-resonance, and simulate circuits.
Automobile electronic systems place high demands ontoday’s DC/DC converters. They must be able to preciselyregulate an output voltage in the face of wide temperatureand input voltage ranges—including load dump transientsin excess of 60V and cold crank voltage drops to 4V. Theconverter must also be able to minimize battery drain inalways-on systems by maintaining high effi ciency over abroad load current range. Similar demands are made bymany 48V nonisolated telecom applications, 40V FireWireperipherals and battery-powered applications with autoplug adaptors. The LT3437’s best in classperformancemeets all of these requirements in a small thermallyenhanced 3mm × 3mm DFN package.
Avalanche photo diode (APD) receiver modules arewidely used in fi ber optic communication systems. AnAPD module contains the APD and a signal conditioningamplifi er, but is not completely self contained. It stillrequires signifi cant support circuitry including a highvoltage, low noise power supply and a precision currentmonitor to indicate the signal strength. The challenge issqueezing this support circuitry into applications withlimited board space. The LT®3482 addresses this challengeby integrating a monolithic DC/DC step-up converter andan accurate current monitor. The LT3482 can supportup to a 90V APD bias voltage, and the current monitorprovides better than 10% accuracy over four decades ofdynamic range (250nA to 2.5mA).
Photomultipliers (PMT), avalanche photodiodes (APD),ultrasonic transducers, capacitance microphones, radiationdetectors and similar devices require high voltage,low current bias. Additionally, the high voltage must bepristinely free of noise; well under a millivolt is a commonrequirement with a few hundred microvolts sometimesnecessary. Normally, switching regulator confi gurationscannot achieve this performance level without employingspecial techniques. One aid to achieving low noise is thatload currents rarely exceed 5mA. This freedom permitsoutput fi ltering methods that are usually impractical
基于CC1110單片機公交報站系統主要由CC1110單片機最小系統和WT588D語音模塊組成，提出了如何實現語音報站，通過無線通信SimpliciTI網絡協議實現公交站臺的自動播報和OLCD液晶顯示公交運行的各類信息。結果表明，該公交報站系統報站準確率99%，價格比同類產品下降了300%以上，系統組成結構簡單，提高了系統的抗干擾性和穩定性，也便于攜帶。
Abstract:
The bus stop announcement system based on CC1110 MCU is composed of CC1110 MCU minimum system and WT588D voice module. How to achieve the voice announcing is put forward.The bus-stop will announce automatically and display on the OLCD by means of wireless communication SimpliciTI network protocol. As a result， the bus station stop announcement systems reported 99% accuracy rate， price of similar products declined by 300% or more， system of simple structure， improve the anti-jamming and stability of the power system， it is also portable.
The CAT93C46 is a 1 kb Serial EEPROM memory device which isconfigured as either 64 registers of 16 bits (ORG pin at VCC) or 128registers of 8 bits (ORG pin at GND). Each register can be written (orread) serially by using the DI (or DO) pin. The CAT93C46 features aself−timed internal write with auto−clear. On−chip Power−On Resetcircuit protects the internal logic against powering up in the wrongstate.
Bootloader是微處理器上電時運行的第一段代碼，它可以通過通信接口實現對微處理器內部應用程序的更新升級，為網絡化嵌入式產品的應用程序升級帶來極大的便利。由于目前沒有統一嵌入式系統的Bootloader。基于NEC 78K0系列單片機自編程原理，設計出一個適用于78K0/Fx2系列單片機的Bootloader，并能夠通過單片機串口在線升級應用程序。
Abstract:
Bootloader is the first piece of code executed after microprocessor startup. It makes the embedded product’s firmware update conveniently through communication interface. However， no unified bootloader is available for all kinds of microprocessor products. Based on the principle of self-programming NEC 78K0s’ series， a useful Bootloader which is suitable for 78K0/Fx2s’ series MCU is designed，the design can update the application through serial ports.
The CAT28LV64 is a low voltage, low power, CMOS Parallel EEPROM organized as 8K x 8−bits. It requires a simple interface for in−system programming. On−chip address and data latches, self−timed write cycle with auto−clear and VCC power up/down write protection eliminate additional timing and protection hardware. DATA Polling and Toggle status bit signal the start and end of the self−timed write cycle. Additionally, the CAT28LV64 features hardware and software write protection.
