30 V Low Power Step-Down DC/DC
The new XC9252 DC/DC converter from TOREX has been developed especially for applications which call for high efficiency and low current consumption. In this situation, the possible input voltage is up to 30V.
The induced current consumption in particular is becoming more and more important, and with the XC9252 this is only 30µA in PFM mode at no load. In order to achieve the maximum possible efficiency at higher loads as well, it is possible, by means of the MODE/SYNC pin, to switch to the PWM mode with fixed switching frequency. As an alternative, the PFM/PWM can also be selected with automatic switching. In this case, switching between the modes takes place automatically, depending on the load. By way of the 0.8 V reference voltage (FB) and the appropriate resistors (RFB1, RFB2), the output voltage can be set freely from 1.5 V. In addition, the XC9252 also provides a power-good signal.
This allows the user to monitor the output, whereby the PG pin goes to Low if a 90% threshold on the reference voltage is undercut. Another special feature of the XC9252 is also the free adjustability of the clock pulse, by means of resistance at the ROSC pin, between 280 kHz and 550 kHz. To minimize noise, the clock pulse can also be synchronized with an external pulse signal. Protective mechanisms are also available as usual with this module. These are the protection against overcurrent and short-circuit, whereby the value for the overcurrent can be adjusted. With regard to the behavior after the tripping of one of the protective mechanisms, a choice can be made between Latch and Auto-Restart. Other mechanisms are thermal disconnection at a chip temperature of more than 150 °C, and an undervoltage protection from 2.5V. The circuits are arranged in such a way that the chip, on cooling or in the event of a rise in the voltage, simply reverts to a normal working mode. The use of suitable ceramic capacitors is permissible, and the soft start time can be adjusted externally by way of the SS pin. The permissible operating temperature is specified from -40?C to 105?C. As housing formats, the USP-10B and a TSSOP-16 housing are available.
Advantages of the XC9252:
- Duty Cycle: 100%
- Power Good Signal
- Input voltage: Absolute maximum value: 36V, bursts: 46V (400ms),external synchronisation of the pulse to reduce interference in the AM band
- Free adjustability of the switching frequency between 280 kHz and 550 kHz
- PWM and PFM/PWM controlling with automatic switchover by MODE Pin
- Lowest current consumption: 30?A
If you would like more detailed information, please do not hesitate to contact us.