This application report describes how to interface the DAC8564 digital-to-analog converter (DAC) to the MSP430F449 mixed-signal microcontroller. This document discusses how the internal reference is disabled and enabled through software.

Type: Application Note

RC networks are used to control voltage transients that could falsely turn-on a thyristor. These networks are called snubbers.

Type: Application Note

A new IC zener with low dynamic impedance and wide operating current range significantly simplifies reference or regulator circuit design. The low dynamic impedance provides better regulation against operating current changes, easing the requirements of the biasing supply. Further, the temperature coefficient is independent of operating current, so that the LM129 can be used at any convenient current level. Other characteristics such as temperature coefficient, noise and long term stability are equal to or better than good quality discrete zeners.

Type: Application Note

The Xilinx Virtex-5 FPGA is a family of advanced FPGAs that combine various platforms and speed grades enabling a high level of performance and flexibility. This application note discusses the Virtex-5 FPGA power supply prerequisites in terms of the multiple voltage rail and current level requirements, output sequencing, and startup characteristics. Exemplarily, a power supply solution based on National Semiconductor LM1771 power supply controller and LM3880 sequencer is designed that combines high performance, power density and efficiency.

Type: Application Note

The SMA540B is a product of the SMA Family (Silicon MMIC Amplifiers), it is an NPN transistor integrating a current mirror as biasing. In this way the IC (collector current) can be controlled by setting the current at Bias pin according to IC = 10 * IBIAS. The IBIAS current is easily adjusted using an external resistor (R1). The voltage supply is 3.3V.

Type: Application Note

Most commonly-used electrical temperature sensors are difficult to apply. For example, thermocouples have low output levels and require cold junction compensation. Thermistors are nonlinear. In addition, the outputs of these sensors are not linearly proportional to any temperature scale. Early monolithic sensors, such as the LM3911, LM134 and LM135, overcame many of these difficulties, but their outputs are related to the Kelvin temperature scale rather than the more popular Celsius and Fahrenheit scales. Fortunately, in 1983 two I.C.'s, the LM34 Precision Fahrenheit Temperature Sensor and the LM35 Precision Celsius Temperature Sensor, were introduced. This application note will discuss the LM34, but with the proper scaling factors can easily be adapted to the LM35.

Type: Application Note

The terms 'energy-saving' and 'quiet-running' are becoming very important in the world of variable speed motor drives. Inverter technology is being accepted by a wide range of users in the design of these products, and their use is increasing. For low-power motor control, there are increasing demands for compactness, built-in control, and lower overall-cost. An important consideration, in justifying the use of inverters in these applications, is to optimize the total-cost-performance ratio of the overall drive system. In other words, the systems have to be less noisy, more efficient, smaller and lighter, more advanced in function and more accurate in control with a very low cost.

Type: Application Note

Main Radio Control State Transition Times

Type: Application Note

Optocouplers simplify logic isolation from the ac line, power supply transformations, and the control of polyphase power systems. They help solve problems by keeping ac line noise and transients out of sensitive logic. Fairchild's 6-Pin Dip Optocoupler family, with high surge voltage capability (7500 volts peak ac, 60 Hz, 1 second duration), allows designers to achieve their goals. This paper presents a power triac phase control circuit and contrasts it with the traditional zero- crossing circuit. The example circuit isolates the low level control circuitry from the ac line. It is able to control the speed of a universal motor or brilliance of a lamp. The universal motor is capable of high starting torque and wide speed range - commonly used in mixers, blenders, floor polishers, electric hand and woodworking tools, etc.

Type: Application Note