Overview
The NCP51820, produced by onsemi, is a high-speed half-bridge driver designed specifically for driving enhancement mode (e-mode) gallium nitride (GaN) power switches. This driver is optimized for use in high-speed switching applications, particularly in off-line, half-bridge power topologies such as soft switching full or half-bridge, LLC, active clamp flyback or forward, totem pole PFC, and synchronous rectifier topologies. The NCP51820 features advanced level shift technology, providing a common mode voltage range of -3.5 V to +650 V for the high-side drive and -3.5 V to +3.5 V for the low-side drive, ensuring stable operation in demanding environments.
Key Specifications
| Parameter | Min | Max | Unit | |
|---|---|---|---|---|
| VDD (Low-side and logic-fixed supply voltage) | -0.3 | 20 | V | |
| VDDL (Low-side supply voltage) | -0.3 | 5.5 | V | |
| VDDH (High-side floating supply voltage) | -0.3 | 5.5 | V | |
| VSW (High-side common mode voltage range) | -3.5 | 650 | V | |
| dVSW/dt (Allowable offset voltage slew rate) | 200 | V/ns | ||
| TJ (Operating Junction Temperature) | 150 | °C | ||
| tPDHOFF (HOSNK turn-off propagation delay time) | 25 | 50 | ns | |
| tRL (LOSRC turn-on rising time) | 2 | 4 | ns | |
| tFH (HOSNK turn-off falling time) | 1.5 | 3.0 | ns |
Key Features
- 650 V, Integrated High-Side and Low-Side Gate Drivers
- Recommended for Soft Switching Applications
- UVLO Protections for VDD High and Low-Side Drivers
- Dual TTL Compatible Schmitt Trigger Inputs
- Split Output Allows Independent Turn-ON/Turn-OFF Adjustment
- Source Capability: 1 A; Sink Capability: 2 A
- Separated HO and LO Driver Output Stages
- 1 ns Rise and Fall Times Optimized for GaN Devices
- SW and PGND: Negative Voltage Transient up to 3.5 V
- 200 V/ns dV/dt Rating for all SW and PGND Referenced Circuitry
- Maximum Propagation Delay of Less Than 50 ns
- Matched Propagation Delays to Less Than 5 ns
- User Programmable Dead-Time Control
- Thermal Shutdown (TSD)
Applications
The NCP51820 is well-suited for various high-speed switching applications, including:
- Driving GaN Power Transistors in soft switching full or half-bridge, LLC, active clamp flyback or forward, totem pole PFC, and synchronous rectifier topologies.
- Industrial Inverters and Motor Drives.
- AC to DC Converters.
Q & A
- What is the primary function of the NCP51820?
The NCP51820 is a high-speed half-bridge driver designed to drive enhancement mode (e-mode) GaN power switches in high-speed switching applications.
- What is the common mode voltage range for the high-side drive?
The common mode voltage range for the high-side drive is -3.5 V to +650 V.
- What are the UVLO thresholds for the VDDH regulator?
The UVLO thresholds for the VDDH regulator are VUVTH_VDDH+ > 4.5 V (ON) and VUVTH_VDDH− < 4.3 V (OFF).
- What is the maximum propagation delay of the NCP51820?
The maximum propagation delay is less than 50 ns.
- What is the dV/dt rating for the driver output stages?
The dV/dt rating is up to 200 V/ns for both driver output stages.
- How is the dead-time control configured?
The dead-time control is user-programmable and can be configured using the DT pin.
- What is the thermal shutdown feature?
The thermal shutdown feature is based on the die junction temperature of the device, providing protection against overheating.
- What are the recommended applications for the NCP51820?
The NCP51820 is recommended for driving GaN power transistors in soft switching topologies, industrial inverters, motor drives, and AC to DC converters.
- How does the high-side bootstrap voltage work?
The high-side bootstrap voltage is generated using a bootstrap capacitor, current limiting resistor, and diode, and is regulated by an internal LDO to produce the VDDH voltage.
- What is the significance of the SW pin in the NCP51820?
The SW pin serves as the high-side, gate drive return reference and should be connected to the GaN FET's Kelvin return if available.
