Abstract: A digital RF modulator, an integrated solution that satisfies stringent DOCSIS RF-performancerequirements, takes advantage of modern technologies like high-performance wideband digital-to-analogconversion and CMOS technology scaling. This application note describes the concept and advantages ofa digital quadrature amplitude modulation (QAM) modulator that uses the direct-RF architecture to enablea Cable access platform (CCAP) system.
Abstract: The MAX9930–MAX9933 family of RF controllers and detector can be used in a wide variety of applications. Anideal application is Cable television (CATV) over fiber, where either a RF controller or a RF detector controls the gain of atransimpedance amplifier (TIA). This application note shows how the MAX9930 (RF controller) can be used as either theRF controller or detector.
Abstract: Nonideal Cable dispersive effects can affect system performance. This application note discusses the twomain loss effects related to Cables (skin-effect and dielectric losses), and presents a simple method of modeling theCable for use in standard SPICE simulators.
Power over Ethernet (PoE) is a new development thatallows for the delivery of power to Ethernet-based devicesvia standard Ethernet CAT5 Cable, precluding the need forwall adapters or other external power sources. The PoEspecification defines a hardware detection protocol wherePower Sourcing Equipment (PSE) is able to identify PoEPowered Devices (PDs), thus allowing full backwardscompatibility with non-PoE-aware (legacy) Ethernetdevices.
Linear Technology offers a variety of devices that simplifyconverting power from a USB Cable, but the LTC®3455represents the highest level of functional integration yet. The LTC3455 seamlessly manages power flowbetween an AC adapter, USB Cable and Li-ion battery,while complying with USB power standards, all from a4mm × 4mm QFN package. In addtion, two high efficiencysynchronous buck converters generate low voltage railswhich most USB-powered peripherals require. TheLTC3455 also provides power-on reset signals for themicroprocessor, a Hot SwapTM output for poweringmemory cards as well as an uncommitted gain blocksuitable for use as a low-battery comparator or an LDOcontroller. The PCB real estate required for the entire USBpower control circuit and two DC/DC converters is only225mm2.
Video Cable driver amplifi er output stages traditionallyrequire a supply voltage of at least 6V in order to providethe required output swing. This requirement is usuallymet with 5V supplies by adding a boost regulator or asmall local negative rail, say via the popular LT®1983-3.Such additional circuitry is unnecessary in typical 1VP-Pvideo connections, such as HD component video, if theCable driver amplifi ers simply offer near rail-to-rail outputcapability when powered from 5V.
Avalanche photodiodes (APDs) are widely utilized in laserbased fiberoptic systems to convert optical data intoelectrical form. The APD is usually packaged with a signalconditioning amplifier in a small module. An APD receivermodule and attendant circuitry appears in Figure 1. TheAPD module (figure right) contains the APD and a transimpedance(e.g., current-to-voltage) amplifier. An opticalport permits interfacing fiberoptic Cable to the APD’sphotosensitive portion. The module’s compact constructionfacilitates a direct, low loss connection between theAPD and the amplifier, necessary because of the extremelyhigh speed data rates involved
The MAX9257/MAX9258 programmable serializer/deserializer (SerDes) devices transfer both video data and control signals over the same twisted-pair Cable. However, control data can only be transmitted during the vertical blank time, which is indicated by the control-channel-enabled output (CCEN) signal. The electronic control unit (ECU) firmware designer needs to know how quickly to respond to the CCEN signal before it times out and how to calculate this duration. This application note describes how to calculate the duration of the CCEN for the MAX9257/MAX9258 SerDes chipset. The calculation is based on STO timeout, clock frequency, and UART bit timing. The CCEN duration is programmable and can be closed if not in use.
The SN65LBC170 and SN75LBC170 aremonolithic integrated circuits designed forbidirectional data communication on multipointbus-transmission lines. Potential applicationsinclude serial or parallel data transmission, Cabledperipheral buses with twin axial, ribbon, ortwisted-pair cabling. These devices are suitablefor FAST-20 SCSI and can transmit or receivedata pulses as short as 25 ns, with skew lessthan 3 ns.These devices combine three 3-state differentialline drivers and three differential input linereceivers, all of which operate from a single 5-Vpower supply.The driver differential outputs and the receiverdifferential inputs are connected internally to formthree differential input/output (I/O) bus ports thatare designed to offer minimum loading to the buswhenever the driver is disabled or VCC = 0. Theseports feature a wide common-mode voltage rangemaking the device suitable for party-lineapplications over long Cable runs.
The MSP-FET430PIF is a Parallel Port interface (does not include target board) that is used to program and debug MSP430 FET tools and test boards through the JTAG interface. This interface is included in our FET tools, but sold without the development board. This interface uses a Parallel PC Port to communicate to the Debugger Software (IAR Kickstart software included) running on the PC. The interface uses the standard 14 pin header to communicate to the MSP430 device using the standard JTAG protocol.
The flash memory can be erased and programmed in seconds with only a few keystrokes, and since the MSP430 flash is extremely low power, no external power supply is required. The tool has an integrated software environment and connects directly to the PC which greatly simplifies the set-up and use of the tool. The flash development tool supports development with all MSP430 flash parts.
Features
MSP430 debugging interface to connect a MSP430-Flash-device to a Parallel port on a PC
Supports JTAG debug protocol (NO support for Spy-Bi-Wire (2-wire JTAG) debug protocol, Spy-Bi-Wire (2-wire JTAG) is supported by MSP-FET430UIF)
Parallel Port Cable and a 14-conductor target Cable
Full documentation on CD ROM
Integrated IAR Kickstart user interface which includes:
Assembler
Linker
Limulator
Source-level debugger
Limited C-compiler
Technical specifications:
Backwardly compatable with existing FET tool boards.
