Global Sources
EE Times-Asia
Stay in touch with EE Times Asia
EE Times-Asia > Power/Alternative Energy
Power/Alternative Energy??

Step-down DC/DC converter includes LDO, voltage detector

Posted: 22 Nov 2005 ?? ?Print Version ?Bookmark and Share

Keywords:ricoh? r5212d? dc/dc converter? LDO regulator?

Ricoh's R5212D chip

Ricoh Europe has introduced the R5212D single chip step-down DC/DC converter, LDO regulator and voltage detector. This circuit offers a powerful and efficient solution on a minimum of board space by using a HSON6 package and is able to provide two independent supply voltages with supervisory features.

The R5212D is designed for applications requiring multiple supply voltages, either to provide power to two individual circuits or to one chip requiring two supply voltages. There is a possibility to choose for a version, whereby the DC/DC converter and the LDO are sharing one common input, or a version whereby the LDO input is internally connected to the DC/DC converter's output in order to prevent a large voltage differential between the LDO's input and output, resulting in excessive heat dissipation of the LDO at a substantial output current. Since the oscillator frequency of the DC/DC converter is 1.2MHz, small external components can be used to reduce board space. As for protection and safety, the R5212D contains several counter measures, like under voltage lockout (UVLO) in case the input voltage is too low to start-up the product, and output short/over-current protection for both output voltages.

In addition, the product contains a voltage detector, monitoring the DC/DC converter's input voltage, which can be used for reset purposes like a power-on-reset signal at the applications start-up sequence or in case, when the DC/DC converter's input voltage drops below the threshold voltage. Two voltage detector versions are available, a version with an active reset time of 12ms or 50ms, requiring no external capacitors. The two output voltages can be set individually.

- Henri Arnold

Electronics Express Europe


Article Comments - Step-down DC/DC converter includes L...
*? You can enter [0] more charecters.
*Verify code:


Visit Asia Webinars to learn about the latest in technology and get practical design tips.

Back to Top