Recom Introduces DC/DC Converter with Medical-Grade IsolationNovember 04, 2020 by Gary Elinoff
The new, inexpensive 0.5 watt device is available in a space-stingy SOIC-16 package
The new R05CT05S works with input voltages ranging from 4.5 – 5.5 volts. The output is externally selected via the TRIM pin.
Image courtesy of Recom
Available choices are fully regulated, low-noise outputs of 5.0 or 3.3 VDC for direct connection to a load. Alternatively, 3.7 or 5.4VDC can be selected to power a downstream low dropout regulator (LDO) for ultra-low-noise applications. The maximum input current is 200 mA.
Image courtesy of Recom Data Sheet
The new medical-grade power supply is specced at a 2.5 million hour meant time between failure (MBTF) rating when operating at 55°C. When operated with only convection cooling, the device can deliver its full half-watt output over a temperature range of -40 to +55 °C with only 20% derating at 110°C. While there is no minimum load requirement, efficiency is a function of load and the output voltage chosen. Under optimal conditions, efficiency is 60%.
Isolation of the R05CT05S is 5k VAC/1min. It achieves a reinforced/800VAC rating to IEC 62368-1 and a 2MOPP/250VAC rating to IEC-60601-1 for medical applications at up to 5000 meters altitude. The part’s isolation capacitance is 3.5pF (typ), which makes the device suitable for applications such as high-side gate driver power supplies, where high common-mode, switched voltages are often encountered.
“The R05CT05S is a breakthrough product for us”, commented Matthew Dauterive DC/DC Product Manager of RECOM. “The part is offered at a price-point where it can be considered for general use such as in COM port or industrial PLC I/O power isolation, IoT/IIoT sensors and smart metering as well as in more critical application areas such as gate drives, medical and industrial, where the high shock, vibration, temperature and isolation ratings are a real benefit”.
Other Important Specifications
Quiescent current, depending on voltage outputs are opted for, ranges from 40 to 80 mA. With DC-DC turned off, maximum standby current is 100 µA.
Switching frequency (typical) is 8 MHz. If desired, an external clock signal can be employed to synchronize multiple R05CT05S units.
Output ripple noise (20MHz BW) is 50 mV peak-to-peak (typ).
Protection features include short-circuit immunity, under-voltage lockout, and over-temperature shutdown.
What is an SOIC Package?
A small outline integrated circuit (SOIC) is noted for having a far smaller footprint than a similar dual inline package (DIP) IC would require. The reduction in the third dimension’s size, noted as either thickness or height is generally even more pronounced.
The R05CT05S is available in an SOIC-16 package, which means that it has 16 pins. It is offered in a 10.3 x 7.5 mm SMD package. Its height profile is 2.6 mm, which makes it suitable for card-type applications. This is because at this low height, the device isn’t higher off the board than the other surface mount technology (SMT) components in its proximity, which might not be the case other than for the benefits of the SOIC package.
Physical and Environmental Considerations
Pending Regulatory Approvals Include
- CSA/CAN C22.2 No. 62368-1
The unit can operate over a temperature range of -40 to +150 °C