Allegro MicroSystems AHV85111 Self-Powered Isolated GaN FET Driver
Allegro MicroSystems AHV85111 Self-Powered Isolated GaN FET Driver is designed to drive GaN FETs in multiple applications and topologies. The AHV85111 integrates an isolated dual positive/negative output bias supply, eliminating the requirement for any external gate drive auxiliary bias supply or high-side bootstrap. The bipolar output rails, with adjustable and regulated positive rail, improve dv/dt immunity, dramatically simplify the system design, and reduce EMI through decreased total common-mode (CM) capacitance.
The Allegro AHV85111 Driver can power a floating switch in any location with a switching power topology. The device has a fast propagation delay and high peak source/sink capability to drive GaN FETs in high-frequency designs efficiently. The device is ideal in applications demanding isolation, level-shifting, or ground separation for noise immunity by implementing high CMTI combined with isolated outputs for both bias power and drive.
The AHV85111 is housed in a compact, low-profile surface-mount NH package. The device provides several protection features, including integrated undervoltage lockout on primary and secondary bias rails and internal pull-down on IN and OUTPD pins. A fast response enables input, overtemperature shutdown, and OUT pulse synchronization with the first IN rising edge after allowing (avoids asynchronous runt pulses).
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Features
- Transformer isolation barrier
- Power-thru integrated isolated bias
- No need for a high-side bootstrap
- No need for external secondary-side bias
- AEC-Q100 Grade 2 qualification
- Bipolar drive output with adjustable regulated positive rail
- Built-in primary-side 3.3V REF bias output
- 50ns propagation delay
- Supply voltage of 10.8V <VDRV <13.2V
- Enable pin with fast response
- Undervoltage lockout on primary VDRV and secondary VSEC
- Continuous ON capability with no need to recycle IN or recharge the bootstrap capacitor
- CMTI > 100V/ns dv/dt immunity
- 8.4mm creepage distance
- Safety regulatory approvals
- 5kVRMS VISO per UL 1577
- 8kV pk VIOTM maximum transient isolation voltage
- 1kV pk maximum working isolation voltage
Applications
- AC-DC and DC-DC converters, including totem-pole PFC, LLC half-/full-bridge, SR drive, multi-level converters, and phase-shifted full-bridge
- Automotive, including EV chargers and OBC
- Industrial, including data center, transportation, robotics, audio, and motors
- Clean energy, including micro-, string, and solar inverters
Typical Application
FUNCTIONAL BLOCK DIAGRAM
Associated Evaluation Board
Learn More About
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Development Boards
Allegro MicroSystems AHV8511x Development Boards (APEK8511xKNH)
Designed to evaluate and demonstrate the AHV85110 isolated GaNFET gate drivers.