Analog Hotspot

What's more important in new product announcements- new levels of performance, or the availability of design tools that make those performance levels accessible? Many designers no longer have the luxury of enough development time to breadboard, refine, and test circuits assembled from parts from multiple chip vendors-assuming designers aren't paying too much of a premium for what the marketing people call a "platform" or a "solution." ...

Apair of 2.4-GHz transceivers from Maxim Integrated Products exemplifies state-of-theart design reuse in RF ICs. These zero-IF, RF transceiver chips both provide an RF-to-baseband receive path, baseband-to-RF transmit path, voltage- controlled oscillator (VCO), frequency synthesizer, crystal oscillator, and baseband/ control interface. The MAX2830 adds an RF power amplifier (PA) rated at 17.1 dBm and a transceive and antenna diversity switch. It...

The International Radio Consultative Committee (CCIR) has developed a testing process that uses human subjects to determine audio quality in digital systems that use lossy compression. Testers play selected recorded material for panels of listeners, who rate the impairments they hear in categories from 5.0 (transparent) to 1.0 (very annoying). To qualify listeners, testing starts with an "ABX" test procedure. In each trial, the listener is pseudorandomly presented...

How do you test audio gear analytically? Audio Precision has some useful white papers on its Web site, including "Fundamentals of Modern Audio Measurement" (http://ap.com/download/Fundamentals_Modern_Audio_Meas.pdf), which first appeared in the Journal of the Audio Engineering Society. If you're more interested in mixed-signal audio measurements, check out Cirrus Logic's "Personal Computer Audio...

If you're designing the analog portions of audio systems, it helps to know two things: what your listeners expect, and how you're going to objectively demonstrate that you're delivering on those expectations. Yet it's difficult to relate engineering measurements to the subjective experience of hearing. The idea that hearing isn't a linear continuum started to crystallize for me in June. National Semiconductor wanted to show me some products it had optimized for the ...

The collapse of the I-35 bridge in Minneapolis on August 1 was a catastrophe. But it should provoke a greater effort to monitor the movement and stresses of buildings, bridges, and rail tracks using strain gauges, piezo sensors, and other inputs receiving vibration sensor data. For designers, that means a need for low-frequency and ultra-low-frequency filters. The eponymously named AnadigmFilter1 chip set is available as a circuit-board module as well. It...

Sometimes it can lighten your day to find a chip that seems to be intended to be its own worst enemy, even if it really isn't. The data sheet for Maxim Integrated Products' MAX109 8-bit, 2.2-Gsample/s analog-to-digital converter (ADC) lists radar warning receivers and light detection and ranging (LIDAR) speed-detection guns as its first two target applications. In the automotive market, radar detectors are supposed to warn speeders of a police presence. But LIDAR...

Dear Bob: Recently I had problems paralleling MOSFETs in a power current source for an electronic load that has to absorb the power generated by four strings of two series-connected BP585 PV modules: (MaxPower_worst-case) = 4(36 V 5 A), about 720 W. The MOSFETs operate in their linear regime, but almost all parts I can buy from my company suppliers are optimized to switching applications. (That's what their maker says, but that does not mean they cannot be...

Previously, selecting high-precision rate and acceleration sensors with six degrees of freedom involved painful cost/performance tradeoffs and elaborate implementation and calibration processes. Now, Analog Devices' ADIS16355 inertial measurement unit (IMU) combines three axes of angular rate sensing and three axes of acceleration sensing with 50 times more accuracy than other off-the-shelf inertial sensors. And it comes pre-calibrated. One version comes...

Do time-based licensees of EDA flows really own their layout data? Not unless they convert it into a format like GDSII. Without licenses, proprietary databases are just clumps of locked binary data. Today’s designers must maintain licenses to access legacy design data. This is the reason for the popularity of formats like Verilog, SDC, GDSII, and LEF/DEF for design data. Designers need open standards and database access to ensure access to their design...

In the age of convergence, analog and full-custom design is reasserting itself as a crucial aspect of almost all system-level designs. While analog content is growing by leaps and bounds in most IC designs, productivity for analog designers is not. In the early days of analog design, layouts for discrete devices on ICs were created by what is colloquially referred to as "polygon pushing." Devices were put together through juxtaposing rectangular shapes on metal layers...

Bob: An induction motor pulls nameplate current at nam-plate rpm. If it is being used as a generator, the slip is opposite what is experienced when the device is used as a motor, but rated power is produced at about the same absolute slip. If connection is made between the mains and motor/generator at any speed between rated motor full-load rpm and synchronous speed plus rated slip, the current must be equal to or less than nameplate current. The service factor rating even...

The CDCE421 low-phase-noise low- voltage positive emitter coupled logic/low-voltage differential signaling (LVPECL/LVDS) clock generator from Texas Instruments provides 380-fs (rms at 10 kHz to 20 MHz) jitter performance (see the figure). The generator’s crystal-oscillator/frequency synthesizer supports output frequencies from 10.9 to 766.7 MHz and from 875.2 to 1175 MHz for Ethernet, Fibre Channel, PCI...

The DS26519 from Dallas Semiconductor reduces cost per port in channel service units, data service units, multiplexers, switches, routers, channel banks, and test equipment. This 16-port, T1/E1/J1 long- and short-haul transceiver doesn’t need any mechanical relays for redundancy protection because it uses what Dallas calls “hitless protection switching,” which presents high impedance at transmit outputs and receive inputs whenever there’s no...

Metastability, which essentially means chaotic output behavior resulting from input glitches, can be a source of system failures in clock distribution. Input glitches are inevitable in hot-swap applications. Micrel’s latest LVPECL/LVDS fanout buffers, though, prevent unwanted oscillations and maintain output stability when an input signal’s swing collapses or disappears. The “Fail-Safe Input” (FSI) family includes the SY89467U (LVPECL) ...

With a new breed of analog/mixed-signal foundries arriving on the scene, fabless and fab-lite companies can create a huge variety of high-yielding designs. As a result, these fabless and fab-lite companies are able to successfully compete with the IDMs in the analog/mixed-signal market. These companies offer something different than traditional CMOS foundries with analog libraries, and it's useful to understand the difference. Pure-play CMOS...

I've been debating with a guy who argues that a transistor won't work as a transistor unless its VCE is bigger than its VBE (see figure) . He keeps reading this in books. Also, he points out that if the base and collector are nominally tied together to make a diode,...

Dallas Semiconductor/Maxim brings the memory shopping mall to you. With a 2-kbit (256 by 8) EEPROM, 12 user-programmable I/O channels, a real-time clock/calendar/alarm, CPU reset monitor, 64-bit factory-programmed ROM ID, battery monitor, and watchdog timer, the DS28DG02 (see figure) offers...

Hi Bob: Just read Bob's Mailbox from the April 12 issue with great interest—in particular, the letter from Terry Hosking about audio capacitors and your reply. It seems to me that the audio field above all others is one beset by pseudoscience and pure wooly thinking. (I tend to agree. /rap) As someone who earns his living as an electronics engineer, but also was a...

I recently saw Prince in concert at 3121, the Las Vegas club customized for his show. Having seen a couple of his arena shows, I already knew that Prince was one of the best live performers out there. The opportunity to see him up close was definitely worth the time and cost of getting to Vegas. But I forgot my earplugs. I'll confess that I love it loud, especially when we're talking about Prince's top-end sound system, which was customized for the band and the club. We were...