What are the characteristics of MOSFET body diodes?

A body diode is a parasitic diode formed between a source and drain due to MOSFET structure. The following characteristics are described on the datasheet.

  • Drain Reverse Current (Continuous)/Drain Reverse Current (Pulse) IDR/IDRP: MOSFET Body Diode Forward Current is the max allowed.
  • Forward voltage (diode): Drain-source voltage when forward current is applied to VDSF body diode.
  • Inverse recovery-time trr
  • Inverse recovered charge Qrr
  • Peak Reverse Recovery Current Irr This is the time (trr) and charge (Qrr) until the reverse recovery current disappears in the reverse recovery operation of the body diode under the specified measuring conditions. The peak current at that time is Irr.
Table 1: Examples of data sheets
Characteristics Symbol Test Conditions Min Typ Max Unit
Diode forward voltage VDSF IDR = 30.8 A, VGS = 0 V - - -1.7 V
Reverse recovery time trr IDR = 15.4 A, VGS = 0 V
-dIDR/dt = 100 A/μs		 - 135 220 ns
Diode reverse recovery charge Qrr - 0.6 - μC
Diode peak reverse recovery current Irr - 10 - A
Diode dv/dt capability dv/dt dv/dt IDR = 15.4 A, VGS = 0 V, VDD = 400 V 50 - - V/ns
Fig. 1: Diode dv/dt tolerance dv/dt
Fig. 1: Diode dv/dt tolerance dv/dt
Fig. 2: Body diode on equivalent circuit
Fig. 2: Body diode on equivalent circuit

Please also refer to here for body diode description.

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