Many of the more digital-friendly analog ICs include several of the basic analog IC functions such as op amps, low drop out regulators, and much more. In other cases, a historically analog IC such as a digital-to-analog converter (DAC) or analog-to-digital converter (ADC) is taken to a higher level of performance to exceed the capability that a similar circuit would have when integrated with a DSP or MCU. Three examples provide a small glimpse into the analog IC designs that continue to expand with the digital electronics revolution.
ANALOG IC CONVERTS HDTV TO COMPUTER FORMAT
National Semiconductor Corporation's LMH1251 is an integrated 2:1 multiplexing (MUX) video switch that uses analog technology to convert standard and high-definition video (YPbPr) signals to a computer video (RGB) format. The chip allows direct video output from DVD player, games, and other devices to a personal computer monitor. The single chip LMH1251 generates both vertical and horizontal sync signals from standard and high-definition video formats. The analog design uses a color-space conversion matrix resulting in a crisper, cleaner, decoded video image and provides a smaller form factor for easier integration. With 400 MHz of bandwidth in the RGB path, the unit accepts up to 1600 × 1200 UXGA video resolutions and outputs an unaltered RGB video signal. The YPbPr video path has 70 MHz of bandwidth and a smart video detection circuit that automatically senses 480i, 480p, 720p, 1080i, and 1080p video formats. For more information on National's LMH1251 video switch, go tohttp://rbi.ims.ca/4416-502.
LOW-POWER DISSIPATION DAC
Analog Devices Inc. has developed the AD970x series, a low-powered TxDAC®digital-to-analog converter (DAC). The AD970x series reduces up to 70 percent of the power dissipation compared to previous DAC devices. Designed for high-speed performance with low power consumption, the new converters target portable instruments that need to synthesize broadband signals as well as other portable, instrumentation, and communication applications. The units support update rates at 175 mega samples per second (MSPS) with spurious-free dynamic range (SFDR) of 86 dBc and intermodulation (IMD) of 70 to 50 MHz. The AD9707s' power supply operates from 1.7 to 3.6V dissipating 35 mW of power at 3.3V and 12 mW at 1.8V. The devices are available in 28-lead thin-shrink small-outline plastic (TSSOP) package and 32-lead lead-frame chip-scale package (LFCSP). For more information on Analog Devices AD9707 TxDAC, go tohttp://rbi.ims.ca/4416-500.
PROGRAMMABLE ENERGY METERING IC
ST Microelectronics' STPM01 IC employs smart power technology to provide a system solution for metering applications. Using the Rogowski and/or shunt method to measure the active energy in a power line, the unit performs as a single-chip single-phase energy meter or as a peripheral measurement in a microprocessor based single-phase or 3-phase energy meter. The STPM01 has both analog and digital circuitry. The analog part consists of a preamplifier and first order sigma-delta analog to digital converter (ADC) blocks, bandgap voltage reference, low drop out voltage regulator, and a pair of DC buffers. The digital part has system control, clock generator, hard-wired DSP, and SPI interface. The chip supports reactive power measurements, multiple tariffs, and can detect 20 forms of microprocessor-based tampering to protect the meter from electricity theft. For more information on ST Microelectronics' STPM1, go tohttp://rbi.ims. ca/4416-501.