The DC/DC converter iC-WD is for a local 5-V supply from an industrial 24-V industrial net, and is now available in a 3.3 V version. By combining a switching converter with two independent series regulators and stabilized 5 or 3.3 V voltages with a low-power dissipation and low residual ripple can be obtained. The two linear regulator outputs are current-limited and provide 200 mA (VCC) or 25 mA (VCCA). iC-WDL is available with three different output voltage combinations (VCC/VCCA): iC-WDA has 3.3/3.3 V, iC-WDB 3.3/5 V and iC-WDC 5/3.3 V.
The current-regulated down converter with an internal 100 kHz oscillator operates at voltages of between 8 and 36 V and requires only a minimum of extra circuitry, namely an inductor, a back-up capacitor and a current-adjusting resistor. The choice of components enables the level of efficiency to be adjusted to suit the particular application in question; values of 100 μH, 4.7μF and 1Ω are typical. This permits components to be used which are both small and economical.
The circuit monitors the chip temperature and the output voltages and signals any errors at an open-collector output. In order to reduce power dissipation the converter is shutdown in the event of excessive temperature.
The ICs are available as DFN10 package, measuring just 4 mm x 4 mm, and come with a demo board for sampling. The DFN10 package has a thermal pad on its underside for improved heat dissipation. This allows the device to be used with higher ambient temperatures.
Use of the chip in series is aimed at sensor applications, such as encoders, linear scales and light barriers, in 24 V control and automation systems.
iC-Haus GmbH is one of the leading independent German manufacturers of standard ICs (ASSP) and cus-tomized ASIC semiconductor solutions. The company has been active in the design, production and sales of application-specific iCs for industrial, automotive and medical technology since 1984 and is represented worldwide. The iC-Haus cell libraries in bipolar, CMOS and BCD technologies are optimized for the design of Sensor-ASiC, Laser-/Opto-ASiC and Actuator-ASiC devices.
The iCs are assembled either in standard plastic packages or using chip-on-board technology to manufacture complete microsystems, multichip modules or – in combination with sensors – optoBGAs.
Further information is available on the iC-Haus website at www.ichaus.com.