High Efficiency / Low Standby Power 2-Channel Secondary Side Synchronous Rectification Control IC - BD85506F
BD85506F is a 2-channel secondary side Synchronous Rectification (SR) controller for LLC with enhanced abnormality detection function on the secondary side. This IC has a function to detect FET abnormalities such as body diode rectification operation. In addition, it incorporates a high-accuracy overvoltage detection circuit, contributing to improved safety and reduction of external components. For efficiency, the OFF threshold voltage of the synchronous rectifier FET can be adjusted with a resistor. Moreover, by providing the Source monitor pin of each FET, it is possible to monitor the voltage between Drain and Source, and further improvement in efficiency is possible. In the burst operation at light load of the primary side controller, the synchronous rectification operation is automatically placed in the standby state, suppressing the switching power and the circuit current of the IC itself and reducing standby power consumption. The built-in multipurpose comparator can also be used as a low consumption shunt regulator in addition to the abnormality detection comparator. The operating power supply voltage ranges from 5.0 V to 32 V, covering various output voltage lineups. Additionally, by adopting a process with a high withstand voltage of 120 V(Max), it is possible to directly monitor the Drain voltage.
Light Load mode
Under Voltage Lock Out
Operating Temperature (Min.)[°C]
Operating Temperature (Max.)[°C]
- Internal FET Abnormality Detection Function for Secondary Side Synchronous Rectification.
- Internal Overvoltage Detection Circuit (OVP). (Externally adjustable, high accuracy: 2 %)
- Efficiency Improvement by FET OFF Threshold Voltage is Adjustable.
- Source of each FET can be individually monitored.
- Internal Standby Mode Automatic Determination Function.
- Internal Multipurpose Comparator. (It can also be used as a shunt regulator)
- With the Slow Start Function, it is possible to set the FET Abnormality Detection Function at startup and the during the start of Switching Operation
- Wide Input Voltage Range 5.0 V to 32 V
- D1, D2 Pin 120 V (Max) Breakdown Voltage
- Flow Compatible SOP14 Package