FAN3268: Low-Voltage 18V PMOS-NMOS Bridge Driver

The FAN3268 dual 2A gate driver is optimized to drive a high-side P-channel MOSFET and a low-side N-channel MOSFET in motor control applications operating from a voltage rail up to 18V. The driver has TTL input thresholds and provides buffer and level translation functions from logic inputs. Internal circuitry provides an under-voltage lockout function that prevents the output switching devices from operating if the VDD supply voltage is below the operating level. Internal 100kΩ resistors bias the non-inverting output low and the inverting output to VDD to keep the external MOSFETs off during startup intervals when logic control signals may not be present. The FAN3268 driver incorporates MillerDrive™ architecture for the final output stage. This bipolar-MOSFET combination provides high current during the Miller plateau stage of the MOSFET turn-on / turn-off process to minimize switching loss, while providing rail-to-rail voltage swing and reverse current capability. The FAN3268 has two independent enable pins that default to on if not connected. If the enable pin for non-inverting channel A is pulled low, OUTA is forced low; if the enable pin for inverting channel B is pulled low, OUTB is forced high. If an input is left unconnected, internal resistors bias the inputs such that the external MOSFETs are off.

Features

• 4.5V to 18V Operating Range
• Drives High-Side PMOS and Low-Side NMOS in Motor Control or Buck Step-down Applications
• Inverting Channel B Biases High-Side PMOS Device Off (with internal 100kΩ Resistor) when V_DD is below UVLO Threshold
• TTL Input Thresholds
• 2.4A Sink / 1.6A Source at V_OUT=6V
• Internal Resistors Turn Driver Off If No Inputs
• MillerDrive™ Technology
• 8-Lead SOIC Package
• Rated from -40°C to +125°C Ambient

Application Notes