Power MOSFET - Latch-up (LU)

Latch-up (LU)

The equivalent circuit for a MOSFET consist of one MOSFET in parallel with a parasitic BJT (Bipolar Junction Transistor). If the BJT turns ON, it cannot be turned off since the gate has no control over it. This phenomenon is known as 'latch-up', which can lead to device destruction. The BJT can be turned on due to a voltage drop across the p-type body region. To avoid latch-up, the body and the source are typically short circuited within the device package.