High frequency SMPS steps into the gap left by offline AC/DC converters
Astrodyne TDI said that its arbitrary waveform generator (AWG) is an innovative, high frequency, SMPS (switched mode power supply) post regulator for applications requiring pulse currents with high slew rates. These are currently underserved by typical offline AC/DC converters, said the company.
Applications, including semiconductor lasers and pulse plating, which often require that the current transitions from its minimum value to its maximum value high pulse repetition frequency. Astrodyne TDI’s AWG can support high pulse currents and peak power, input overhead voltage to overcome lead inductance during pulse rise time and manage repetitive peak semiconductor power and junction temperature for long term reliability, said the company.
The AWG circuit is built around a synchronous buck topology operating at a switching frequency of 200kHz at full load. The converter features a hysteretic control topology, which varies the switching frequency in response to output load changes. Hysteretic control provides optimal availability of input voltage to drive output current rise time.
Another feature of the AWG, high frequency, switched mode post regulator, is the ability to reverse polarity on the delivered output. The four switches are modulated to set the output polarity as the external host system commands.
The AWG circuit supports high output slew rates with an output capacitor of less than 100 microF (providing around 3 microF per A at 30A) and high current control bandwidth. Converter blocks connected in parallel to support higher output power. For example, when eight of these assemblies are connected in parallel, a semiconductor laser application can achieve slew rates of 8,000A per ms.
The improved AC to pulsed DC output power system can provide output current slew rates greater than 1,000A per ms while managing component reliability considerations resulting from thermal fatigue and safe operating conditions.
Astrodyne TDI designs and manufactures power solutions for demanding applications worldwide. Its products include power supplies and EMI filters for industrial, semiconductor manufacturing, medical, consumer appliance, military and aerospace markets. The company has over 60 years’ of power supply design experience, and is headquartered in Hackettstown, New Jersey, USA, and has engineering and manufacturing centres in the USA and China.
