Gate Driving for High-Voltage Converters: Understanding Isolated Gate Drivers

The MP188x1 Series: A Robust, Dual-Channel Isolated Gate Driver Family with Capacitive Isolation

Gate drivers control the commutation of power switches, such as field-effect transistors, and are used in many high-voltage applications, including solar inverters, uninterruptible power supplies, charging stations, and on-board chargers. Isolating the power path from the sensitive control signals protects the user and prevents malfunctions. Electrical isolation barriers can be implemented in three ways: inductive, optical, or capacitive isolation. Capacitive isolation offers the best performance regarding isolation voltage, reliability, and form factor, which is why MPS’s isolated gate drivers use capacitive isolation.

Features:

• The MP18851 includes two independent channels and drives two transistors separately in a single chip
• The MP18831 implements a half-bridge switching topology, including dead-time control to avoid shoot-through
• The MP18871 single-input gate driver simplifies driving circuits by having the controller provide a PWM signal to control the duty cycle
• Accurate switching control while allowing for the appropriate dead time and safety features
• CMTI above 100kV/µs enables faster switching without affecting signal integrity

Relevant Detail Pages

• MP18851
• MP18831
• MP18871