Low Voltage/Low Saturation 2-CH DC Motor Driver# Technical Documentation: FAN8100MTC Half-Bridge Gate Driver IC
Manufacturer : FAIRCHILD (now part of ON Semiconductor)
Component : FAN8100MTC
Description : Monolithic Half-Bridge Gate Driver IC
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## 1. Application Scenarios
### Typical Use Cases
The FAN8100MTC is a high-voltage, high-speed power MOSFET and IGBT driver designed to operate in a half-bridge configuration. Its primary function is to provide the necessary gate drive signals for two N-channel power switches (high-side and low-side) in synchronous switching topologies.
Primary Applications Include:
* Motor Drive Systems : Brushed DC (BDC) and Brushless DC (BLDC) motor control in applications requiring precise speed and torque management. The half-bridge configuration is fundamental for building three-phase inverter stages.
* Switch-Mode Power Supplies (SMPS) : Used in high-efficiency DC-DC converters, particularly in synchronous buck and half-bridge topologies for computing, telecom, and industrial power systems.
* Class D Audio Amplifiers : Drives the output stage power MOSFETs in high-efficiency audio amplification systems.
* Solenoid and Actuator Drivers : Provides robust switching for inductive loads in automotive and industrial control systems.
### Industry Applications
* Automotive : Electric power steering (EPS) pumps, engine cooling fans, HVAC blower motors, and window lift systems. Its ability to handle high-voltage transients makes it suitable for the 12V automotive electrical environment.
* Industrial Automation : Drives for conveyor belts, robotic arms, and pump controllers. Its integrated bootstrap function simplifies high-side drive in noisy industrial environments.
* Consumer Appliances : Inverter controls for compressor drives in refrigerators and air conditioners, as well as high-efficiency washing machine motor drives.
* Computing : Voltage Regulator Modules (VRMs) for CPU/GPU power delivery on motherboards and graphics cards.
### Practical Advantages and Limitations
Advantages:
* Integrated Bootstrap Function : Eliminates the need for a separate, isolated high-side power supply, significantly reducing component count and board space.
* Shoot-Through Protection : Features a built-in interlock dead time (typically ~520ns) that prevents both high-side and low-side switches from conducting simultaneously, a critical safeguard against catastrophic shoot-through currents.
* High-Speed Operation : Fast propagation delays and rise/fall times enable high-frequency switching (up to several hundred kHz), improving power density and transient response.
* Robustness : High dV/dt immunity, under-voltage lockout (UVLO) for both channels, and a wide operating voltage range enhance reliability in harsh electrical environments.
* Compact Package (TSSOP-14) : Offers a small footprint suitable for space-constrained applications.
Limitations:
* Bootstrap Capacitor Limitations : The high-side drive is only active when the low-side switch is turned on to recharge the bootstrap capacitor. This limits the maximum allowable high-side switch on-time (duty cycle), especially at very low frequencies or during startup.
* Negative Voltage Transients : While robust, the IC can be susceptible to damage from large negative voltage spikes on the VS (high-side floating supply return) pin, which can exceed its absolute maximum rating. External clamping is often necessary.
* Heat Dissipation in TSSOP Package : The small package has limited thermal dissipation capability. Careful PCB thermal design is required for high-current, high-frequency applications to avoid junction temperature exceedance.
* Fixed Dead Time : The internal dead time is fixed. For applications requiring optimized efficiency across a wide load range, an external, adjustable dead-time circuit may be preferable.
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## 2. Design Considerations
### Common Design Pitfalls and Solutions
