STMicroelectronics A6983I Iso-Buck Converter is specifically created for isolated buck topology. The primary output voltage on the A6983I can be accurately adjusted, whereas the isolated secondary output is derived using a given transformer ratio. No optocoupler is required. The primary sink capability up to 4.5A (even during soft-start) permits a proper energy transfer to the secondary side and allows a tracked soft-start of the secondary output. The control loop supports a peak current mode architecture, and the STM A6983I operates in forced PWM. The 390ns blanking time filter oscillations generated by the transformer leakage inductance make the solution more robust.
The compact QFN-16 (3mm x 3mm) package and the internal compensation of the A6983I help minimize the design complexity and size. The switching frequency can be programmed in the 200kHz to 1MHz range with an optional spread spectrum for improved EMC.













