Consumer

Application Notes

Simple Program Compresses Scripts, Saves Memory When Using  Multiformat Video Decoders

AN-1050: A Method for Compressing I²C Scripts for the ADV74xx/ADV75xx/ADV76xx/ADV78xx

This 20-page Application Note, which describes a method for compressing large sets of I²C scripts for microcontroller platforms, is targeted at applications where the user needs to put over 50 scripts into the memory of a single microcontroller. It includes a script for a free (GNU/GPL license) Octave program, which can compress scripts and export the results to the C code with decompressing procedures.

On-Chip Filter Minimizes False Triggers in Electrically Noisy Environments

AN-1048: AD7150 On-Chip Noise Filter

The AD7150, AD7151, and AD7156 capacitance-to-digital converters measure capacitance between two electrodes and compare the result with a threshold that can be either fixed or dynamically adjusted by the on-chip adaptive threshold algorithm engine. If the input capacitance increases above the threshold, an output flag is set to indicate proximity. In electrically noisy environments, the sensor electrodes function like an antenna, picking up unwanted noise from the surroundings. For high-sensitivity applications, the on-chip noise filter can prevent unwanted triggers caused by noise signals on the capacitive input. This 2-page Application Note describes the functionality of the on-chip noise filter.

New Product Briefs

March 2010

Low-power embedded Blackfin Processors with consumer-device connectivity

The ADSP-BF51x and ADSP-BF51xF Blackfin^® processors, optimized for cost-sensitive applications—including portable test equipment, embedded modems, biometrics, and consumer audio—combine the multimedia signal-processing power of a single-instruction, multiple-data (SIMD) DSP with the control capabilities of a RISC microcontroller. With two 16-bit MACs, two 40 bit ALUs, four 8-bit video ALUs, and 116K bytes of on-chip memory, they operate at up to 400 MHz. Peripherals, depending on model, include: IEEE 802.3-compliant 10/100 Ethernet MAC with IEEE 1588 support; DMA controller; removable-storage interface (RSI) controller; two-wire interface (TWI) controller; dual-channel, full-duplex synchronous serial ports (SPORTs) that support 8 channels of I²S stereo audio; UARTs; SPI port; general-purpose timers; watchdog timers; real-time clock; parallel peripheral interface (PPI), supporting ITU-R 656 video formats; rotary counter; 3-phase PWM pairs; and general-purpose I/Os. F-suffix devices add 4-Mbits of SPI flash memory. Lockbox™ security technology protects code and content. Dynamic power management adjusts the operating voltage and frequency, optimizing power consumption vs. performance for real-time applications. All Blackfin processors are supported by the VisualDSP++ software-development environment and the EZ-KIT Lite evaluation system. Available in 168-ball CSP-BGA and 176-lead LQFP packages, the ADSP-BF51x and ADSP-BF51xF are specified over 0°C to +70°C or –40°C to +85°C temperature ranges. Pricing starts at $6.27 in 1000s.

Isolated Half-Bridge Driver provides 4-A peak output currents

The ADuM7234 isolated half-bridge gate driver uses iCoupler^® technology to provide independent, isolated outputs for driving the gates of the high-side and low-side IGBT and MOSFET devices used in plasma displays, switching power supplies, and industrial inverters. Combining high-speed CMOS with monolithic micro-transformers, iCoupler technology provides precise timing, high reliability, and better overall performance than optocoupler-based systems. Each output can be driven up to ±350 V_PEAK with respect to the input and with a differential of up to 350 V_PEAK working voltage between the high side and the low side. Switching at up to 1 MHz, the outputs can provide 4-A peak currents. The CMOS-compatible inputs provide 25-kV/μs common-mode transient immunity. Operating on a 4.5-V to 5.5-V input supply, the ADuM7234 consumes 1 mA. Available in a 16-lead SOIC package, it is specified from –40°C to +105°C and priced at $1.82 in 1000s.

Very-Low-Dropout Regulators drive loads of up to 500 mA

The ADP124 and ADP125 low-dropout regulators are available in 31 fixed-output options from 1.75 V to 3.3 V (ADP124) and a 0.8-V to 5-V adjustable output (ADP125). With ±1% initial accuracy and –2/+1.5% accuracy over line, load, and temperature, they feature 130-mV dropout voltage with a 500-mA load. Stable with tiny ceramic input and output capacitors, their robust design features a fixed 350-µs soft-start time, short-circuit protection, and thermal-overload protection. Operating on a single 2.3-V to 5.5-V supply, the ADP124/25 draw 210 μA at full load, 45 μA with no load, and 100 nA in shutdown mode. Available in 8-lead exposed-paddle mini-SOIC packages, which improve junction-to-board thermal resistance to 32°C/W vs. standard MSOP package, they are specified from –40°C to +125°C and priced at $0.42 in 1000s.

February 2010

Quad low-power, low-noise, wideband Operational Amplifier has rail-to-rail output

The ADA4691-4 quad low-power operational amplifier draws only 165 µA per amplifier while operating from a single 2.7-V to 5.5-V supply or dual ±1.35-V to ±2.5-V supplies. Two pairs of amplifiers can be powered down independently, reducing power consumption to 10 nA in shutdown mode. Featuring 500-μV offset, 1‑μV/°C offset drift, 0.5-pA bias current, 90-dB common-mode rejection, 3.6-MHz bandwidth, 1.1-V/μs slew rate, 16‑nV/rt-Hz noise, and 0.006% distortion, the amplifier is ideally suited for instrumentation, portable audio, and medical applications. The input range extends below the negative rail, and the output can swing to within 30 mV of either rail, providing true single-supply capability. Specified from –40°C to +125°C, and available in a 16‑lead LFCSP package, it is priced at $0.90 in 1000s.

Mobile I/O Expander and QUERTY Keypad Controller

The ADP5587 port expander and keypad controller features keypad scanning, debouncing, and I/O generation, resulting in simplified routing, reduced processor involvement, and lower power consumption. Offloading key-scan and GPIO functions from the CPU, it enables the processor to control up to 18 data lines—configured as an 8 x 10 keypad matrix or as general-purpose I/Os—via an I²C-compatible bus. Storing key presses and releases, and flagging them to the processor, the controller manages all mobile key scanning and decoding functions. This enables portable devices with QWERTY keypads to use three control lines instead of 18, reducing cost and improving reliability. A key-event counter allows the device to manage up to ten unprocessed key events, while the key-lock capability can trigger an interrupt when the lock sequence is activated. Operating on a 1.7-V to 3.6-V power supply, the ADP5587 draws 55 μA at 1.8 V. Specified from –40°C to +85°C, it is available in a 24-lead LFCSP package and priced at $1.15 in 1000s.

January 2010

Low-power HDMI Receiver

The AD9393 low-power 80-MHz HDMI v1.2a and DVI v1.0 receiver accepts HDTV formats up to 720p/1080i and graphic resolutions up to XGA (1024 × 768 @ 75 Hz)—and provides RGB and YCrCb outputs for high-definition TVs, projectors, and other portable displays. High-definition content protection allows secure reception of protected content, as specified by the HDCP v1.1 protocol. The receiver supports S/PDIF for stereo- or compressed audio and I²S for 7.1-channel surround sound. Operating on 1.8‑V and 3.3‑V supplies, the AD9393 consumes 593 mW in YCrCb mode and 530 mW in RGB mode. Available in a 6-mm × 6-mm 76-ball CSP BGA package, it is specified from –10°C to +80°C and priced at $5.09 in 1000s.

24-bit, 96-kHz, low-noise stereo Audio Codec with SigmaDSP processing core

The ADAU1781 low-power stereo audio codec provides high-quality audio for digital video and -still cameras. Supporting 24-bit data at 8‑kHz to 96-kHz sampling rates, it achieves 96-dB dynamic range and –90-dB harmonic distortion (THD+N). The record path includes two digital stereo microphone inputs, an analog stereo input—which can be configured for a pseudo-differential or single-ended source—and an analog beep signal, which can be mixed into any output. The playback path includes a stereo line output, and a speaker driver that is capable of driving 400 mW into an 8-ohm load. The programmable SigmaDSP^® core provides enhanced record and playback processing to improve overall audio quality. The control bus is compatible with I²C and SPI protocols; the audio bus is programmable for I²S, left/right justified, and TDM modes; and a phase-locked loop (PLL) generates sampling clocks based on master clock rates from 11 MHz to 20 MHz. Operating on a 1.8-V to 3.65-V supply, the ADAU1781 consumes 16 mA. Available in a 32-lead LFCSP package, it is specified from –25°C to +85°C and priced at $3.20 in 1000s.

Step-down DC-to-DC Converter provides two 3-A outputs or single 6-A output

The ADP2116 high-efficiency step-down dc-to-dc converter is available in six fixed-output options, from 0.8 V to 3.3 V, plus an adjustable-output option that can be set as low as 0.6 V. Featuring output accuracy to within 1.5% and 95% efficiency, it can be configured to deliver: a pair of independent 3-A outputs, 3-A and 2-A outputs, or a single, interleaved 6-A output with reduced output ripple. The switching frequency can be set to 300 kHz, 600 kHz, or 1.2 MHz—or it can be synchronized to an external clock in the 200-kHz to 2-MHz range. Optimized gate slew-rate reduces EMI emissions. The robust design features programmable soft-start time, short-circuit- and thermal-overload protection, and under-voltage lockout. Operating on a single 2.7-V to 5.5-V supply, the ADP2116 consumes 3.4 mA with dual independent outputs, 3 mA with a single output, and 1 µA in shutdown mode. Available in a 32‑lead LFCSP package, it is specified from –40°C to +125°C and priced at $3.17 in 1000s.

Dual 3-MHz, 600-mA Buck Regulator with 150-mA LDO

The ADP5022 micropower management unit (micro PMU) combines two high-performance buck (step-down) regulators and a low-dropout (LDO) linear regulator in a single small package. Further minimizing PC-board space requirements, the buck regulators’ high switching frequency allows the use of tiny external components; and the two bucks operate out of phase to use smaller input capacitors while reducing noise. Normally operating in PWM mode, they draw 24 µA per channel, automatically switching to power-saving mode to improve light-load efficiency. Drawing 11 µA, the LDO has a dropout voltage of 7 mV with a 10-mA load and 110 mV with a 150-mA load. The ADP5022 is available in three factory configured options: the -1 has 3.3-V and 1.5-V buck outputs, 1.8-V LDO output, and 2.4-V undervoltage lockout; the -2 has 1.2-V and 1.8-V buck outputs, 2.8-V LDO output, and 2.4-V undervoltage lockout; and the -3 has 3.3-V and 1.8-V buck outputs, 3.3-V LDO output, and 4.5-V undervoltage lockout. Available in a 16-ball WLFCSP package, the ADP5022 is specified from –40°C to +125°C and priced at $1.80 in 1000s.

Pre-Release Products

January 2010

The ADSP-BF51x and ADSP-BF51xF Blackfin Processors—optimized for cost-sensitive applications including portable test equipment, embedded modems, biometrics, and consumer audio—combine the multimedia signal-processing power of a single-instruction, multiple-data (SIMD) DSP with the control capabilities of a RISC microcontroller. With two 16-bit MACs, two 40 bit ALUs, four 8-bit video ALUs, and 116K bytes of on-chip memory, they operate at up to 400 MHz. Peripherals, depending on model, include: IEEE 802.3-compliant 10/100 Ethernet MAC with IEEE 1588 support; DMA controller; removable-storage interface (RSI) controller; two-wire interface (TWI) controller; dual-channel, full-duplex synchronous serial ports (SPORTs) that support 8 channels of I²S stereo audio; UARTs; SPI port; general-purpose timers; watchdog timers; real-time clock; parallel peripheral interface (PPI), supporting ITU-R 656 video formats; rotary counter; 3-phase PWM pairs; and general-purpose I/Os. F-suffix devices add 4-Mbits of SPI flash memory. Lockbox™ security technology protects code and content. Dynamic power management adjusts the operating voltage and frequency, optimizing power consumption vs. performance for real-time applications. All Blackfin processors are supported by the VisualDSP++ software-development environment and the EZ-KIT Lite evaluation system.

Technical Articles

Gareth Finn, New Touch-Screen Controllers Offer Robust Sensing for Portable Displays, Analog Dialogue, 2/2/2010

Lie Dou and David McMahon, HDMI 1.4-based high speed interface, Development forecast 2010, EE Times China, 1/7/2010

Webinars and Tutorials

Introduction to Op Amps -- This presentation is an introductory discussion of operational amplifiers (op amps) and is intended for users that are new to or unfamiliar with analog design or concepts.

Amplifier Noise Principles for the Practical Engineer -- This presentation will focus on practical noise tips for the board designer, rather than theoretical aspects often covered in academic texts.

Powering FPGAs - Learn the Basics -- This webinar describes the special power requirements for FPGAs and the appropriate power products used to ensure trouble free operation. A versatile dc-to-dc regulator that is optimized for powering high-performance FPGAs is featured.

VFB or CFB -- That is the question! -- Why is it that voltage feedback amplifiers seem to dominate the op amp landscape compared to current feedback amplifiers?

What's the big deal about ABSOLUTE MAXIMUM RATINGS? -- Is it alright to exceed just one of the parameters in the ABSOLUTE MAXIMUM RATINGS table, by just a little bit?

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