Overview
The LM5109A 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. It is capable of working with rail voltages up to 90V and features independent TTL compatible input thresholds. The device utilizes robust level shift technology to operate at high speed while consuming low power and providing clean level transitions from the control input logic to the high-side gate driver. Under-voltage lockout is provided on both the low-side and the high-side power rails. The LM5109A is available in industry-standard SOIC-8 and thermally enhanced WSON-8 packages.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Peak Output Current (Source/Sink) | 1A / 1A | A |
| Bootstrap Supply Voltage | Up to 108V | V |
| Propagation Times | 30 ns (typical) | ns |
| Rise/Fall Times | 15 ns (typical) | ns |
| Propagation Delay Matching | 2 ns (typical) | ns |
| Supply Voltage Range | 8 V to 14 V | V |
| Operating Temperature Range | -40°C to 125°C | °C |
| Package Types | SOIC-8, WSON-8 | |
| Logic Voltage (VIL, VIH) | 0.8V, 2.2V | V |
Key Features
- Drives both high-side and low-side N-Channel MOSFETs
- 1A peak output current (1.0A sink / 1.0A source)
- Independent TTL compatible inputs
- Bootstrap supply voltage up to 108V DC
- Fast propagation times (30 ns typical)
- Drives 1000 pF load with 15ns rise and fall times
- Excellent propagation delay matching (2 ns typical)
- Supply rail under-voltage lockout
- Low power consumption
- Pin compatible with ISL6700
- Industry standard SOIC-8 and thermally enhanced WSON-8 packages
Applications
- Current Fed push-pull converters
- Half and Full Bridge power converters
- Solid state motor drives
- Two switch forward power converters
Q & A
- What is the peak output current of the LM5109A?
The peak output current of the LM5109A is 1A (1.0A sink / 1.0A source). - What are the package options for the LM5109A?
The LM5109A is available in SOIC-8 and thermally enhanced WSON-8 packages. - What is the maximum bootstrap supply voltage for the LM5109A?
The maximum bootstrap supply voltage for the LM5109A is up to 108V DC. - What are the typical propagation times for the LM5109A?
The typical propagation times for the LM5109A are 30 ns. - What is the operating temperature range for the LM5109A?
The operating temperature range for the LM5109A is -40°C to 125°C. - Does the LM5109A have under-voltage lockout?
Yes, the LM5109A has under-voltage lockout on both the low-side and the high-side power rails. - What type of logic inputs does the LM5109A support?
The LM5109A supports independent TTL compatible inputs. - What are some typical applications for the LM5109A?
Typical applications include current fed push-pull converters, half and full bridge power converters, solid state motor drives, and two switch forward power converters. - Is the LM5109A pin compatible with other devices?
Yes, the LM5109A is pin compatible with the ISL6700. - How does the LM5109A manage heat dissipation?
The LM5109A, especially in the WSON package, benefits from soldering the exposed pad to the ground plane on the PCB to improve heat dissipation.
