Flyback Controller – Getting started
A flyback controller is a dedicated IC that’s designed to regulate a flyback converter. Click the different boxes in the diagram below to read more about each feature.
- Output is regulated directly from the output. An optocopuler is recommended to maintain isolation.
- Output is regulated from the auxiliary winding. This simplifies the design by eliminating the optocopuler based feedback network.
- Typical for lower power levels, current fully discharges from transformer every switching cycle.
- Typical for higher power levels, special DCM case where switch turns on at first valley to reduce switching losses.
- Typical for some operating points in higher power levels, current always conducts through the transformer.
- Dissipative clamp replaced with lossless active clamp, which is used to achieve zero voltage switching and drastically improve efficiency
- Electrical switch that’s turned on and off by an external voltage.
- Electrical switch that is turned on and off by an injected current.
Cable Compensation (CBC)
- Output voltage increases at predetermined amounts as output current increases to compensate for resistive losses on long cables, enabling tight regulation at true output at end of cable.
- Output voltage increases at user programmable amounts as output current increases to compensate for resistive losses on long cables, enabling tight regulation at true output at end of cable.
- Output voltage fixed, regardless of output current magnitude.
Constant Voltage (CV)/Constant Current (CC) Control
- When output reaches max current the output turns into a constant current source, preventing current from exceeding max current threshold.
- When output reaches max current the output turns into a constant power source, with the output voltage decreasing with increasing output current.
Negative Temperature Coefficient (NTC) Resistor Interface
- Direct connection with a negative temperature coefficient interface resistor, enabling external over temperature shutdown protection in addition to internal protection limit.
- No direct connection with a negative temperature coefficient. Over temperature protection is dependent on internal limit of device.