L6388ED

PMIC - Gate Drivers: L6388ED application field and working principle

The L6388ED is a gate drive IC designed primarily for driving the gate of high-side N-channel power MOSFETs in power-switching applications. It has been designed to drive power MOSFETs with switching frequencies up to 400kHz as well as low RDS(ON) MOSFETs. This device provides protection against over-voltage, under-voltage and over-current conditions, as well as slew-rate limiting for improved noise immunity.

Device Description

The L6388ED is a full bridge, high-side, low-side driver IC. The device features low-side drivers (which are also adjustable) and an adjustable high-side driver that enables external voltage sensing for improved protection. The low-side drivers are controlled by TTL-compatible levels, while the high-side driver is controlled by a high-voltage CMOS level. A high current drive capability is provided by integrated NMOS transistors mating with the device ICs high-side driver.

Features and Benefits

• High speed switching performance (up to 400kHz)
• High current drive capability
• Low controller power consumption
• Low power consumption
• High efficiency operation
• Integrated N-channel MOSFETs
• Undervoltage lockout protection circuits
• Overcurrent protection circuit
• Improved noise immunity with slew-rate limiting

Application Fields

The L6388ED gate driver IC is primarily intended for high-side N-channel power MOSFETs used in automotive engine control, motor vehicle power transmission systems, power supplies, Uninterruptible Power Supplies (UPS), motor drives and power conversion applications. These are high-power applications where high efficiency and low noise are key requirements.

Working Principle

The working principle of the L6388ED gate driver IC is based on the standard control scheme for power MOSFETs. The device is operated in a push-pull circuit configuration with the high-side and low-side drivers directly controlling the gate-source potential of the power switches. The high-side driver is controlled by a high-voltage CMOS level and the low-side drivers by low-voltage TTL-compatible levels. A separate enable input is provided to enable or shut off the drive to the power switch.

The enable input is particularly useful as it can be used to turn off the drive to the power switch. This is particularly important if the load current is expected to go beyond the device’s current limit. The device has over-current protection circuits which are triggered in case the load current goes beyond the anticipated current limit. The device also has over-voltage and under-voltage protection circuits.

The L6388ED gate driver IC is capable of handling switching frequencies up to 400kHz and can be used with low RDS(ON) MOSFETs. The device has an adjustable high-side driver which enables external voltage sensing for improved protection and improved power efficiency. The device also has slew-rate limiting for improved noise immunity.

Conclusion

The L6388ED is a gate drive IC designed primarily for driving the gate of high-side N-channel power MOSFETs in power-switching applications. It features low-side drivers and an adjustable high-side driver that enables external voltage sensing for improved protection. The device has high speed switching performance, high current drive capability, low controller power consumption and low power consumption. It is primarily intended for high-power applications where high efficiency and low noise are key requirements and can operate at switching frequencies up to 400kHz.

The device has over-voltage, under-voltage and over-current protection circuits as well as slew-rate limiting for improved noise immunity. The working principle of the device is based on the standard control scheme for power MOSFETs with the drive to the power switch turned on and off using a separate enable input.