Power Converters Reference

Overview of DC-DC and AC-DC converter topologies.

Reference Reference Updated Apr 19, 2026
Reference

DC-DC topologies

Topology V_out vs V_in Isolation Use
Buck V_out < V_in No Step-down, general
Boost V_out > V_in No Step-up from battery
Buck-boost Either No Inverted polarity
Ćuk Either No Two inductors, low ripple
SEPIC Either No Single-inductor alternative
Flyback Either Yes Low-mid power (< 200 W)
Forward Either Yes Medium power (50–500 W)
Push-pull Either Yes Medium power
Half-bridge Either Yes Medium-high power (200 W – 1 kW)
Full-bridge Either Yes High power (kW+)
LLC resonant Either Yes High efficiency, high power
Phase-shifted full bridge Either Yes Server PSUs, EV chargers
Charge pump Integer ratios No Low-power on-chip rails

AC-DC

  • Linear: transformer + rectifier + LDO — simple, heavy, low-efficiency.
  • Switching (offline): rectifier + PFC + isolated converter (flyback, LLC).
  • PFC stage: mandatory for > 75 W (IEC 61000-3-2) to meet harmonic limits.
  • Bidirectional: for EV / grid-tied inverters — PWM inverter + LC filter.

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