Digital products still require an extensive amount of analog circuitry to interface to an analog world. Analog integrated circuits (ICs) drive LEDs (and other displays), convert dc voltage levels for the system loads, amplify signals, filter noise, control motors, and convert power from ac to dc. Here are five products with enabling analog circuitry.
RECHARGEABLE LED FLASHLIGHT
Angus Noble Indium Torch. Innovative designer Angus Noble used Lithium-ion battery technology with the latest high intensity LEDs to produce a small, powerful, and rechargeable light source. To eliminate any moving parts and ensure maximum reliability, a touch sensitive switch controls the light. The touch switch's analog circuitry selects between different ways of driving the MOSFET that provides power to the LEDs. Either the LEDs are off, on for full power, driven by a simple high-frequency oscillator for half power, or driven by a low-frequency oscillator for flashing mode. The Indium can be recharged from a computer USB port. For more information on the Angus Noble Indium Torch, go to http://rbi.ims.ca/4388-541.
HIGH MOBILITY ROBOT
Wowwee Robotics Robosapien V2 (http://rbi.ims.ca/4388-542). This 2-ft tall walking wonder interacts with objects, people, and other family robots. The brush dc motors for the robot's motion are controlled by Freescale Semiconductor's MPC17550, a monolithic quad H-bridge that integrates four independent power H-bridges and a 12V output dc-dc boost converter. The SMARTMOS™ analog IC controls forward, reverse, brake, and high-impedance functions by input logic from the robot's digital controls. Each leg of the H-bridge has an Rds(on) of 0.7V (typical) and can handle an output current of 700 mA (dc), 2.0A (peak). For more information on Freescale's MPC17550 , go to http://rbi.ims.ca/4388-543.
INTELLIGENT STUN GUN
Taser International Taser X26 (http://rbi.ims.ca/4388-544). The X26 delivers two separate energy pulses to disable the bad guys. The initial high voltage (50,000V) with low-current pulses penetrates clothing. Once an arc is established, a low-current, low-voltage pulse train stuns the victim. Digital pulse control technology limits the time between pulses to conserve power. LEDs provide status and a liquid crystal display (LCD) indicates the amount of remaining battery life. Onboard analog circuitry provides power conversion, drives LEDs and the LCD Panel, and switches the high-voltage energy pulses—about 0.36J with 52 msec between pulses.
AIR TRAFFIC TRACKING SYSTEM
AeroStream Communications Corp. Traffic Information System (TIS) (http://rbi.ims.ca/4388-545). If all planes were equipped with a TIS, every pilot would have an onboard version of an air traffic control display. The GPS-based system provides a low-cost alternative to radar, identifying planes by taking L-band readings. The design uses the AD9874 from Analog Devices' (ADI's) Mixed-Signal Front-End (MxFE™) family to link the received data stream to an ADI Blackfin processor's serial port. The analog portion of the mixed signal chip includes an amplifier, mixer, sigma delta analog-to-digital converter (ADC) and filter to reduce the components needed to complete the signal chain and to provide lower power consumption. For more information on Analog Devices' AD9874, go to http://rbi.ims.ca/4388-546.
ADAPTIVE MOBILE PHONE HEADSET
Aliph Jawbone Headset (http://rbi.ims.ca/4388-547). This headset uses high-performance audio processing technology and adapts to continuously improve audio quality. A voice activity sensor in the headset determines when the user is speaking, and Texas Instruments' (TI's) TMS320C5405 digital signal processor with Jawbone's proprietary software continuously samples the environment's background noise, and then subtracts those sounds from the speech signal. Engineers used several TI analog ICs to increase power efficiency and performance. TI's TPS76927 low-dropout (LDO) voltage regulators provide ultra-low quiescent current and TI's TPS6220x 300-mA dc/dc step-down converter provides up to 95 percent power efficiency to extend battery life. For more information on Texas Instruments' TPS6220x, go to http://rbi.ims.ca/4388-548.