Power

Torex - XC9242/43 Series, 2A Synchronous Step-Down DC/DC Converters

17th May 2011
ES Admin
0
The new XC9242/43 series from Torex is a group of synchronous step-down DC/DC converters that can be used with ceramic capacitors and integrates one P-channel and one N-channel MOS power transistors. The small on-resistance of these power transistors permits to obtain high efficiencies for output currents up to 2A. The XC9242/43 operates with input voltages VIN ranging between 2.7V and 6.0V, and its output voltage can be set between 0.9V and VIN by using two external resistors.
We all know that IC’s using PWM control (such as the XC9242) tend to exhibit a very clean output voltage under all load conditions. However, thanks to a proprietary design from Torex, IC’s that use PWM/PFM control (such as the XC9243) can too maintain a very low output voltage ripple under all loads conditions, while exhibiting other typical advantages of PWM/PFM control such as a high efficiency over a wide range of load conditions.

The XC9242/43 series is available with two different switching frequencies, 1.2MHz for applications where a higher efficiency is critical, and 2.4MHz where space is at a premium and when high speed line and load transient responses are required.

The XC9242/43 series will be forced to stop operating by various protection circuits, such as a thermal shutdown circuit when the chip’s temperature reaches 150ºC and a UVLO (Under Voltage Lock Out) circuit when the input voltage decreases below 2.5V. Both of the above functions are implemented using hysteresis, and will allow the XC9242/43 to resume normal operation when the chip’s temperature drops below 130ºC and when the input voltage increases to 2.68V respectively. In addition to these protections, the XC9242/43 comprises a current limiter that not only stops the IC when the output current is too high, but also permits the IC to automatically resume normal operation (following a soft-start procedure) as soon as the over-current condition disappears.

Others features of the XC9242/43 series include a chip enable pin to turn the IC on and off, a CL discharge function to quickly discharge the output capacitor when the IC is turned off, and the aforementioned high speed soft-start circuit.

Because of the very low on-resistance of its two built-in power transistors, the XC9242/43 chip dissipates less power and can thus be integrated in a small 2.9 x 2.6mm USP-10B package.

Product Spotlight

Upcoming Events

View all events
Newsletter
Latest global electronics news
© Copyright 2024 Electronic Specifier