onsemi MUR2020RG Ultrafast Rectifier: Datasheet, Pinout, and Application Circuit Guide
The onsemi MUR2020RG is a high-efficiency, ultrafast recovery rectifier designed for high-frequency power conversion applications. Its exceptional switching characteristics and rugged construction make it a preferred choice for engineers designing switch-mode power supplies (SMPS), inverters, and freewheeling diodes. This guide provides a detailed look into its datasheet, pinout, and a typical application circuit.
Datasheet Overview and Key Specifications
The MUR2020RG belongs to a family of rectifiers renowned for their ultrafast recovery time, which is crucial for minimizing switching losses and improving overall efficiency in high-frequency circuits. Key electrical characteristics extracted from the datasheet include:
Repetitive Peak Reverse Voltage (VRRM): 200 V
Average Forward Output Current (IF(AV)): 20 A
Peak Forward Surge Current (IFSM): 300 A (non-repetitive)
Forward Voltage Drop (VF): Typically 0.975 V at 10 A
Reverse Recovery Time (trr): A maximum of 60 ns, which is critical for its ultrafast performance.
The device is housed in a robust TO-220AB package, ensuring excellent thermal performance and ease of mounting on a heatsink for power dissipation. Its operational junction temperature range is from -65°C to +175°C, guaranteeing reliability under strenuous conditions.
Pinout and Package Information
The MUR2020RG utilizes a standard TO-220AB package with three leads. The pinout configuration is straightforward:
1. Pin 1 (Anode): This is the positive terminal of the diode.
2. Pin 2 (Cathode): This is the negative terminal of the diode and is connected to the central tab.
3. Pin 3 (No Connection - NC): This pin is internally disconnected and serves no electrical function. It is often cut short for mechanical stability during assembly.
The metal tab is electrically connected to the cathode (Pin 2). Proper isolation between the tab/heatsink and the chassis is mandatory if they are at different potentials.
Typical Application Circuit: SMPS Output Rectifier
One of the most common applications for the MUR2020RG is as an output rectifier in a switch-mode power supply. The following describes its role in a typical flyback or forward converter configuration.
In the circuit, the MUR2020RG is placed in series with the secondary winding of the transformer. Its function is to convert the high-frequency alternating current (AC) from the transformer into direct current (DC). The ultrafast recovery feature is vital here; a slow diode would lead to significant reverse recovery current, causing large switching losses, electromagnetic interference (EMI), and potential voltage spikes that could damage other components.
To ensure stable operation and protect the diode, the circuit often includes:
A snubber network (a resistor and capacitor in series) across the diode to suppress voltage overshoot.
An LC filter (inductor and capacitor) at the output to smooth the rectified DC voltage.
ICGOODFIND: For engineers seeking reliable and high-performance rectification solutions, the onsemi MUR2020RG stands out as a top contender. Its robust 200V/20A rating, exceptional ultrafast recovery time, and industry-standard TO-220 package make it an indispensable component for optimizing efficiency and reliability in modern power electronics designs, from industrial equipment to consumer power adapters.
Keywords: Ultrafast Recovery Rectifier, Switch-Mode Power Supply (SMPS), Output Rectifier, TO-220 Package, Reverse Recovery Time.
