LLC Converter (Full Bride, Synchronous FETs)
Description
The LLC converter is a resonant converter that can achieve ZVS operation (primary side switch) and ZCS operation (secondary side switch) simultaneously. It achieves low noise and high efficiency by generating a sinusoidal current waveform with the switch network and resonant circuit.
This circuit consists of a full-bridge switch circuit on the primary side and a center-tap transformer on the secondary side using FETs instead of diodes. This type of configuration is commonly used for relatively high power (around several kW).
Overview
- Same semiconductor devices
- Series resonance between Cr and Lr
- Lr is sometimes implemented as the leakage inductance of the transformer
- Voltage control is done through frequency high complexity design
- Soft switching is defined by magnetizing inductance Lm, not function of the load.
- Efficiency around 98% suits Titanium!
- Frequency 100..200 kHz
Circuit
Key Products
Product Category | Product family | Product Number | Feature |
---|---|---|---|
Primary Side (HV) | 600V SJ MOS | PrestoMOS (JNx series) | excellent switching behaviour (low Qrr, short Trr) |
Secondary Side (LV) | 100V MOSFET | RQ3P300BH | 100V MOSFET in small HSMT8 package |
40V MOSFET | RS1G300GN | 40V MOSFET in HSOP8 package | |
Gate Driver | HV side | BM60212FV-C | Dual driver, ideal for half- and full-bridge topologies. |
LV Side | BD85506F | Synchronous rectification controller IC |
Simulation
Coming soon
Related Topologies
LLC Converter (Full Bridge, Diode Rectification)