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Dual Hall sensor detects rotation direction and speed Infineon has developed a vertical dual-Hall sensor for detecting rotation direction and speed. Delivered in a TSOP-6, the TLE4966V is the first dual-Hall device with its integrated Hall plates oriented vertically instead of horizontally on the chip surface, making it sensitive to magnetic fields with in-plane direction. This 90-degree orientation change provides flexibility to fit designs into space-constrained areas. Its design flexibility and low current consumption make the TLE4966V suited for energy-sensitive electronic automotive systems such as trunk lifts, power window lifts, sun roofs and seat adjustment. In non-automotive applications, the sensor can also be utilized for escalators, motorized window blinds and shades. The sensor is an extension of Infineon’s TLE4966 family frequently used in window lifter and other index counting applications. This product family is designed to detect the rotation direction and rotation speed of a magnetic pole wheel. The vertically integrated Hall plates in the new TLE4966V enable sensing of in-plane, instead of perpendicular, magnetic fields. Changing sensing orientation by 90 degrees allows system engineers to design new and previously unattainable mechanical concepts, in particular for for space-restricted applications such as power window lifts and electronic trunk lifts. Detecting the direction and speed of rotation of a magnetic pole wheel requires two separate Hall plates. Due to the distance between the two plates, they detect slightly different signals at any time. This is termed the phase difference. During a rotation direction change, the phase difference changes polarity. The TLE4966V detects this change and delivers a corresponding signal. The rotation speed of a magnetic pole wheel can directly be calculated with the second sensor output signal. This signal is triggered by each polarity change of the magnetic field. The two integrated vertical Hall plates on a single silicon die within the TLE4966V feature the same behaviour for temperature and lifetime stress, with no sensitivity deviation over lifetime. Furthermore, the TLE4966V has two signal outputs: one signal for the magnet rotation direction, the other signal for the pole wheel rotation speed. Infineon www.infineon.com Wide-dynamic-range, high-accuracy RF power detectors Analog Devices has added two RF power detectors with wide dynamic range and high levels of accuracy and temperature stability. ADL5903 is a solution for a variety of high frequency systems requiring accurate measurement of signal power independent of waveform characteristics. The ADL5506 RF detector is a complete subsystem for the measurement of RF signals in a wide range of wireless terminal devices. Both detectors come in small packages with low-power operation. Analog Devices www.analog.com Digital PWM controller for high-current, non-isolated DC-DC power supplies Micrel has introduced a true-digital PWM controller for highcurrent, non-isolated DC-DC power supplies in computing and telecom applications. Designed to work with an external industry standard DrMOS as well as Micrel’s proprietary IntelliMOS solution, the MIC21000 can be used as a flexible building block for +12 V or +5 V step-down, high current point-of-load power supplies. The MIC21000 meets designers’ challenges by integrating a digital control loop, optimized for maximum flexibility and stability, as well as for load transient and steady state performance. The MIC21000’s ultra-fast transient response reduces the output capacitance. The non-linear control feature improves transient response by a factor of two versus competing analog solutions. Highly reliable fuse-based, on-board nonvolatile memory (OTP NVM) and I2C/PMBUS interface enable user configuration and communication with a supervisory controller for monitoring and fault management. This allows for rapid power subsystem development and debugging which, in turn, accelerates time to market. The I2C/PMBUS interface allows for real time monitoring of input voltage, output voltage/current and internal/external temperature. The MIC21000 can operate from a single bias supply voltage of 5 V or 3.3 V. A full suite of power management features eliminates the need for complicated and expensive sequencing and monitoring of the IC. Micrel www.micrel.com Reversible DC motor driver saves space and boosts power efficiency Diodes Incorporated has introduced a single-chip IC for driving single-coil reversible DC fans and motors. A highly integrated device, in a choice of SO8 and thermally enhanced SO8 exposed pad packages, the ZXBM5210 reduces component count and circuit footprints in medium voltage, low-power applications in consumer, domestic appliance, industrial and office equipment. The driver’s integrated high-performance H-bridge output stage can deliver currents as high as 700 mA continuous, 1.2 A peak and has been designed to meet stringent low noise requirements by minimizing both audible switching noise and electromagnetic interference. Its generous supply range of 3 V to 18 V means the device will support a wide variety of single phase 5 V, 9 V, 12 V and 15 V DC motors. Typical operating current is a low 0.85 mA. Achieving highly linear speed control, the ZXBM5210 has four modes of operation: forward, reverse, brake and standby, which are selected via the device’s FWD and REV input pins. Motor speed is regulated by modifying the duty ratio of PWM signals applied to the two inputs or by adjusting the DC input voltage to the VREF input pin. The PWM oscillator is integrated within the device and no external timing capacitor is required. The ZXBM5210’s standby mode consumes a typical current of 32μA. To prevent damage to either the motor coil or driver IC, the ZXMB5210 incorporates under-voltage lockout, overvoltage, over-current and thermal shutdown protection functions. Diodes Incorporated www.diodes.com www.electronics-eetimes.com Electronic Engineering Times Europe January 2014 29


EETE JAN 2014
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