MOSFET Driver supports buck or boost DC/DC converters.

Press Release Summary:




Operating from up to 38 V supply, synchronous Model LTC4449 drives upper and lower N-channel MOSFET gates over range of 4-6.5 V. Unit can sink up to 4.5 A and source up to 3.2 A. Adaptive shoot-through protection prevents upper and lower MOSFETs from conducting simultaneously while minimizing dead time. Housed in 2 x 3 mm DFN-8 package, IC features 3-state PWM input for power stage control and shutdown and is available in industrial-grade version that operates from -40 to 125°C.



Original Press Release:



High Speed Synchronous N-Channel MOSFET Driver Has Powerful Gate Drive for High Efficiency Buck or Boost DC/DC Converters



MILPITAS, CA - Linear Technology Corporation introduces the LTC4449, a high speed synchronous MOSFET driver designed to drive upper and lower power N-channel MOSFETs in a synchronous rectified converter topology. This driver, combined with one of Linear Technology's DC/DC controllers and power FETs forms a complete high efficiency synchronous regulator that can be used as a step-down or step-up DC/DC converter.

The LTC4449 drives both upper and lower MOSFET gates over a range of 4V to 6.5V and operates from a supply voltage up to 38V. This powerful driver can sink up to 4.5A and source up to 3.2A, making it ideal for driving high gate capacitance and high current MOSFETs. It can also drive multiple MOSFETs in parallel for higher current applications. The fast 8ns rise time, 7ns fall time of the top MOSFET and 7ns rise time, 4ns fall time of the bottom MOSFET, when driving a 3,000pF load, minimize switching losses. Adaptive shoot-through protection is integrated to prevent the upper and lower MOSFETs from conducting simultaneously while minimizing dead time.

The LTC4449 features a 3-state pulse with modulation (PWM) input for power stage control and shutdown that is compatible with all multiphase controllers employing a 3-state output feature. In addition, the LTC4449 has a separate supply for the input logic to match the signal swing of the controller IC, as well as an undervoltage lockout circuit on both the driver and logic supplies.

The LTC4449EDCB is available in a 2mm x 3mm DFN-8 package, priced starting at $1.25 each in 1,000-piece quantities. The Industrial grade version, LTC4449IDCB, is guaranteed to operate over a -40ºC to 125ºC operating junction temperature range and is priced at $1.39 each in 1,000-piece quantities. All versions are available from stock. For more information, visit www.linear.com.

Summary of Features: LTC4449

Synchronous N-Channel MOSFET Driver

4V to 6.5V Gate Drive VCC Voltage

38V Maximum Supply Voltage

Adaptive Shoot-Through Protection

Three-State PWM Input for Power Stage Control

High Drive Current - 3.2A Source, 4.5A Sink

Top Gate: 8ns Rise Time, 7ns Fall Time when Driving 3000pF

Bottom Gate: 7ns Rise Time, 4ns Fall Time when Driving 3000pF

2mm x 3mm DFN-8 Package

About Linear Technology

Linear Technology Corporation, a manufacturer of high performance linear integrated circuits, was founded in 1981, became a public company in 1986 and joined the S&P 500 index of major public companies in 2000. Linear Technology products include high performance amplifiers, comparators, voltage references, monolithic filters, linear regulators, DC-DC converters, battery chargers, data converters, communications interface circuits, RF signal conditioning circuits, µModule® products, and many other analog functions. Applications for Linear Technology's high performance circuits include telecommunications, cellular telephones, networking products such as optical switches, notebook and desktop computers, computer peripherals, video/multimedia, industrial instrumentation, security monitoring devices, high-end consumer products such as digital cameras and MP3 players, complex medical devices, automotive electronics, factory automation, process control, and military and space systems.
LT, LTC, LTM, µModule and are registered trademarks of Linear Technology Corp. All other trademarks are the property of their respective owners.

All Topics