Multi-topology current-mode PWM controller for isolated supplies
The Maxim Integrated MAX5094DAUA+ is a current-mode PWM controller designed for flyback and forward converter topologies, delivering a single transistor-driver output with positive, isolation-capable configuration. It operates from a 7.6 V to 30 V supply rail and switches from 10 kHz to 500 kHz, suiting a wide range of isolated DC-DC converter designs in industrial power supplies, motor drives, and telecom equipment where the -40°C to 125°C junction temperature range is required.
49.8% duty cycle — what it means for the transformer
The 49.8% maximum duty cycle is a deliberate limit: in a flyback converter it ensures adequate reset time for the transformer core, preventing saturation. For forward converters, it keeps the volt-second product within the core's capability. This cap means the controller is suited for designs where the off-time needs to be at least as long as the on-time, a common constraint in single-ended topologies.
Switching frequency flexibility: 10 kHz to 500 kHz
The adjustable switching frequency from 10 kHz to 500 kHz lets the designer trade off transformer size against switching losses. At the low end, larger magnetics but lower core losses; at the high end, smaller transformers and faster transient response, but higher gate-drive losses. The frequency is set by an external resistor tied to the Frequency Control pin, giving the layout engineer control over the noise spectrum.
Lifecycle and sourcing
The MAX5094DAUA+ is listed as Active on Maxim Integrated's product status, with ROHS3 compliance.