1 Features

1• Drives Both a High-Side and Low-Side N-Channel

MOSFET

• 1-A Peak Output Current (1.0-A Sink and 1.0-A

Source)

• Inputs Compatible With Independent TTL and

CMOS

• Bootstrap Supply Voltage to 108-V DC

• Fast Propagation Times (30 ns Typical)

• Drives 1000-pF Load With 15-ns Rise and Fall

Times

• Excellent Propagation Delay Matching (2 ns

Typical)

• Supply Rail Undervoltage Lockout

• Low Power Consumption

• 8-Pin SOIC and Thermally-Enhanced 8-Pin

WSON Package

2 Applications

• Current-Fed, Push-Pull Converters

• Half- and Full-Bridge Power Converters

• Solid-State Motor Drives

• Two-Switch Forward Power Converters

3 Description

The LM5109B device is a cost-effective, high-voltage

gate driver designed to drive both the high-side and

the low-side N-channel MOSFETs in a synchronous

buck or a half-bridge configuration. The floating

high-side driver is capable of working with rail

voltages up to 90 V. The outputs are independently

controlled with cost-effective TTL and

CMOS-compatible input thresholds. The robust level shift technology operates at high speed while

consuming low power and providing clean level

transitions from the control input logic to the high-side

gate driver. Undervoltage lockout is provided on both

the low-side and the high-side power rails. The

device is available in the 8-pin SOIC and thermally- enhanced 8-pin WSON packages.