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An efficient method of detecting combustion engine knock is using spectral analysis. The detection process algorithm adapts to a no-knock reference at varying speeds and loads by using multiple frequencies. This document presents an problem overview current technology and two implementation examples are given to aid in the development of system specific hardware and software. The first system is

This application report describes a software program for performing V.23 FSK modem transceiver functions using an MSP430 microcontroller. It makes use of novel filter architecture to perform DSP funct

Demonstration circuit DC1708A is a dual-output regulator focused specifically for DDR memory power applications. It is built based on the LTC3634, a high voltage dualchannel, controlled on-time monolithic synchronous buck regulator. The DC1708A has an input voltage range of 3.6V to 15V. The output voltage of the first channel, VDDQ, of the DC1708A has three fixed voltage settings: 1.5V, 1.8V and 2.5V, and is capable of delivering up to 3A of output current. The second channel, VTT, is set to regulate to half the voltage on the VDDQIN pin, which can be either the channel 1 output or an external reference voltage. It can source or sink a maximum of 3A of output current. The LTC3634 also provides a 10mA buffered output of half VDDQIN – VTTR, which is used to provide the reference voltage needed for DDR applications. With the use of a timing resistor, the DC1708A can have its operating frequency programmed from 500kHz to 4MHz. Additionally the DC1708A can be easily synchronized to an external clock, due to an internal phase-locked loop, within this same frequency range. The DC1708A VDDQ output can operate in either Burst Mode® operation or forced continuous mode. In Burst Mode operation, which is the preferred mode of low load current operation, the DC supply current is typically only 1.3mA (both channels) at no load (sleep mode), and less than 15µA in shutdown. In Burst Mode operation or continuous mode operation, the DC1708A is a very efficient circuit at high load currents: over 80% for either channel. The LTC3634 is also capable of 90° or 180° out-of-phase operation, and can allow its output to track an external voltage, either coincidentally or ratiometrically. The LTC3634 comes in a 28-pin QFN package, featuring an exposed pad on the bottom-side of the IC for better thermal performance. All of these features make the DC1708A an ideal circuit for powering DDR memory applications.

DSP/BIOS II is a kernel that provides run-time services which developers use to build DSP applications and manage application resources. DSP/BIOS II effectively extends the DSP instruction set with real-time run-time kernel services that form the underlying architecture or infra-structure of real-time DSP applications.The DSP/BIOS II kernel tightly integrates with the Code Composer Studio (

This application report presents guidelines for interfacing the Texas Instruments (TI(TM)) TLC5510 8-bit parallel-output analog-to-digital converter (ADC) to the TI TMS320C203 DSP data bus. The 8-bit ADC operates at a rate of 20 MHz. The C callable application program (assembly code) used to initialize the TMS320C203 and execute the code is also discussed.This report serves as reference inform

This reference design provides 12V at 10A from a wide range 18V-60V telecom input with greater than 93% efficiency. This design uses the UCC2897A active clamp controller with synchronous rectifiers for an efficient: yet cost effective solution that can operate from either a 24VDC or 48VDC input bus.

This reference design provides an isolated 12V at 10A from a 19V-30V input with greater than 93% efficiency. This design uses the UCC2897A active clamp controller with CSD18532Q5B synchronous rectifiers for an efficient: yet cost effective solution that can operate from a 24VDC input bus.

Although active filters are vital in modern electronics their design and verification can be tedious and time consuming. To aid in the design of active filters Burr-Brown provides a series of FilterPro™ computer-aided design programs. Using the FILTER42 program and the UAF42 it is easy to design and implement all kinds of active filters. The UAF42 is a monolithic IC which contains the op am

This board is the slave unti of PMP4590: adding two more outputs.

When a PFC is in discontinuous conduction mode the inductor current will resonant between the boost inductor and MOSFET parasite capacitance. The resonant current can be big enough to distort the PFC current significantly. This application note introduces a digital control scheme based on UCD3XXX to predict the position at which the resonant current first time rises back from negative to zero a

Feedback plots simplify the analysis of an op amp's closed-loop AC performance by showing bandwidth and stability conditions as a function of the op amp's gain and phase response. These plots also provide insight into noise performance and the special feedback requirements of circuits such as integrating converters photodiode amplifiers composite amplifiers and active feedback circuits.

The LTC2228/LTC2227/LTC2226 are 12-bit 65Msps/40Msps/25Msps, low power 3V A/D converters designed for digitizing high frequency, wide dynamic range signals. The LTC2228/LTC2227/LTC2226 are perfect for demanding imaging and communications applications with AC performance that includes 71dB SNR and 80dB SFDR for signals at the Nyquist frequency.DC specs include ?0.3LSB INL (typ), ?0.15LSB DNL (typ) and no missing codes over temperature. The transition noise is a low 0.25LSBRMS.A single 3V supply allows low power operation. A separate output supply allows the outputs to drive 0.5V to 3.6V logic.A single-ended CLK input controls converter operation. An optional clock duty cycle stabilizer allows high performance at full speed for a wide range of clock duty cycles.Applications Wireless and Wired Broadband Communication Imaging Systems Ultrasound Spectral Analysis Portable Instrumentation

The AD8334 is an ultralow noise, quad channel linear-in-dB variable gain amplifier (VGA). Although optimized for ultrasound systems, it may be used as a low noise variable gain control in any application whose operating frequency is less than 100 MHz.Included in each channel are an ultralow noise preamp (LNA), an X-AMP? VGA with 48 dB of gain range, and a selectable gain postamp with adjustable output limiting. The LNA gain is 19 dB with a single-ended input and differential outputs. Using a single resistor, the LNA input impedance can be adjusted to match a signal source without compromising noise performance.The 48 dB gain range of the VGA makes these devices suitable for a variety of applications. Excellent bandwidth uniformity is maintained across the entire range. The gain control interface provides precise linear-in-dB scaling of 50 dB/V for control voltages between 40 mV and 1 V. Factory trim ensures excellent part-to-part and channel-to-channel gain matching. Differential signal paths result in superb second- and third-order distortion performance and low crosstalk.The AD8334 is a quad version of the single AD8331 and dual AD8332.For information on specs, see the AD8331/AD8332/AD8334 datasheet.Applications Ultrasound and sonar time-gain controls High performance automatic gain control (AGC) systems I/Q signal processing High speed, dual ADC drivers

The AD7879/AD7889 are 12-bit successive approximationanalog-to-digital converters (SAR ADCs) with a synchronousserial interface and low on-resistance switches for driving 4-wireresistive touch screens. The AD7879/AD7889 work with a verylow power supply?a single 1.6 V to 3.6 V supply?and feature athroughput rate of 105 kSPS. The devices include a shutdownmode that reduces current consumption to less than 6 ?A.To reduce the effects of noise from LCDs and other sources, theAD7879/AD7889 contain a preprocessing block. Thepreprocessing function consists of a median filter and anaveraging filter. The combination of these two filters provides amore robust solution, discarding the spurious noise in the signaland keeping only the data of interest. The size of both filters isprogrammable. Other user-programmable conversion controlsinclude variable acquisition time and first conversion delay; upto 16 averages can be taken per conversion. The AD7879/AD7889can run in slave mode or standalone (master) mode, using anautomatic conversion sequencer and timer.The AD7879/AD7889 have a programmable pin that canoperate as an auxiliary input to the ADCs, as a battery monitor,or as a general-purpose input/output (GPIO). In addition, aprogrammable interrupt output can operate in three modes: as ageneral-purpose interrupt to signal when new data is available(DAV), as an interrupt to indicate when limits are exceeded(INT), or as a pen-down interrupt when the screen is touched(PENIRQ). The AD7879/AD7889 offer temperaturemeasurement and touch pressure measurement.The AD7879 is available in a 12-ball, 1.6 mm ? 2 mm WLCSPand in a 16-lead, 4 mm ? 4 mm LFCSP. The AD7889 is availablein a backside coated version of the WLCSP. Both devices supportan SPI interface (AD7879/AD7889) or an I2C interface (AD7879-1/AD7889-1).Applications Personal digital assistants Smart handheld devices Touch screen monitors Point-of-sale terminals Medical devices Cell phones

The LTM2887 is a complete galvanic digital ?Module? (micromodule) isolator. No external components are required. A single 3.3V or 5V supply powers both sides of the interface through an integrated, isolated DC/DC converter. A logic supply pin allows easy interfacing with different logic levels from 1.62V to 5.5V, independent of the main supply.Available options are compliant with SPI and I2C (master mode only) specifications.The isolated side includes two 5V nominal power supplies, including programmable current limit, each capable of providing more than 100mA of load current. The supplies may be adjusted from their nominal value using a single external resistor.Coupled inductors and an isolation power transformer provide 2500VRMS of isolation between the input and output logic interface. This device is ideal for systems where the ground loop is broken, allowing for a large common mode voltage range. Communication is uninterrupted for common mode transients greater than 30kV/?s.Applications Isolated SPI or I2C Interfaces Industrial Systems Test and Measurement Equipment Breaking Ground Loops

This reference design demostrates a low cost single PCB solution for 5V1A cube charger. By using primary side regulation (PSR) mode chip UCC28700: < 30-mW No-Load power is achieved: which meets 5-star rating. The overall size is limited in 22mm(L)X21mm(W)x20mm(H).