onsemi MUR1660CT Ultrafast Rectifier: Datasheet, Pinout, and Application Circuits
The MUR1660CT from onsemi is a high-efficiency, ultra-fast recovery rectifier specifically engineered for high-frequency power conversion applications. This robust component is a common-center-tap dual rectifier, making it an ideal choice for use in switch-mode power supplies (SMPS), inverters, and as freewheeling or clamp diodes. Its ultra-fast recovery time is critical for minimizing switching losses and improving overall system efficiency.
Datasheet Overview and Key Specifications
The MUR1660CT is characterized by its high current capability and low forward voltage drop. Key absolute maximum ratings and electrical characteristics from its datasheet include:
Repetitive Peak Reverse Voltage (VRRM): 600 V
Average Forward Output Current (IF(AV)): 8 A per leg (16 A total, single-phase half-wave, resistive load)
Peak Forward Surge Current (IFSM): 150 A
Forward Voltage Drop (VF): Typically 1.25 V at 8 A (per leg)
Maximum Reverse Recovery Time (trr): 35 ns
Operation Junction Temperature (TJ): -65°C to +175°C
These specifications highlight the diode's ability to handle significant power levels while maintaining swift switching performance, which is essential for suppressing voltage spikes and reducing electromagnetic interference (EMI).
Pinout and Package
The MUR1660CT is offered in the industry-standard TO-220-3L (Modified) package. The pinout configuration is as follows:
Pin 1 (Left): Cathode of Diode 1
Pin 2 (Center): Common Anode (The anodes of both internal diodes are connected to this central pin)
Pin 3 (Right): Cathode of Diode 2
This common-center-tap design is particularly advantageous for building full-wave rectifier circuits, especially in power supply output stages where a center-tapped transformer is used.
Application Circuits
1. Center-Tapped Full-Wave Rectifier: This is the most classic application for the MUR1660CT. The center tap of the transformer's secondary winding is connected to the common anode (center pin), and the two ends of the winding are connected to the two cathodes. This configuration provides full-wave rectification from a center-tapped source, effectively doubling the ripple frequency compared to a half-wave circuit and simplifying the output filtering requirements.
2. Switch-Mode Power Supply (SMPS) Output Rectification: The diode is extensively used in the output rectification stage of high-frequency SMPS. Its fast recovery ensures that the rectifier turns off quickly when reverse-biased, preventing excessive reverse recovery current from circulating and causing high switching losses and potential damage to the switching transistor (e.g., MOSFET).
3. Freewheeling/Clamp Diode in Power Converters: In inductive load circuits like motor drives or relay controllers, the MUR1660CT is used as a freewheeling diode. It provides a safe path for the current to circulate when the driving switch turns off, protecting the switch from damaging voltage spikes caused by the collapse of the magnetic field in the inductor.
The onsemi MUR1660CT stands out as a highly reliable and efficient solution for high-speed rectification. Its balanced combination of high voltage rating, fast recovery, and a common-center-tap package makes it a versatile and preferred component for designers aiming to optimize performance and reliability in demanding power electronics applications.
Keywords: Ultrafast Recovery Rectifier, Switch-Mode Power Supply (SMPS), Center-Tap Rectifier, High-Frequency Conversion, Freewheeling Diode
