New 150VIN & VOUT Synchronous 4-Switch Buck-Boost Controller from Analog Devices
The LTC3777 is ideal for use with a high input voltage range or when high voltage surges are present on the input
Analog Devices announces the release of the LTC3777,
a 150V high efficiency (up to 99%) 4-switch synchronous buck-boost DC/DC controller,
which operates from input voltages above, below or equal to the regulated output voltage.
Its 4.5V to 150V input voltage range operates from a high input voltage source or
from an input that has high voltage surges, eliminating the need for external surge suppression devices,
ideal for transportation, industrial and medical applications.
To prevent high on-chip power dissipation in high input voltage applications, the LTC3777 integrates a low quiescent current high efficiency switching bias supply for its internal power consumption. The output voltage of the LTC3777 can be set from 1.2V to 150V at output currents up to tens of amps, depending on the choice of external components. Output power up to 500W can be delivered with a single device. Higher powers can be achieved when multiple circuits are configured in parallel. The LTC3777’s powerful 1.5Ω N-channel MOSFET gate drivers can be adjusted from 6V to 10V, enabling the use of logic-level or standard-threshold MOSFETs.
The LTC3777 employs a proprietary current mode control architecture for constant frequency in buck, boost or buck-boost modes. The operating frequency can be synchronized to an external clock from 50kHz to 600kHz, while an input/output constant current loop provides support for battery charging and overload protection. The user can select either forced continuous mode or discontinuous mode to maximize light load efficiency. Additional features include seamless transfers between operating regions, a power good output voltage monitor, adjustable soft-start and input overvoltage lockout, and output voltage disconnect during shutdown.
Features of the LTC3777 include:
- 4-Switch Synchronous Current Mode Buck-Boost Architecture
- Operation with Input Voltages Above, Below or Equal to the Output Voltage
- 4.5V to 150V Input Voltage Range
- 1.2V to 150V Output Voltage Range
- Up to 99% Efficiency
- Input or Output Average Current Limit
- Adjustable 6V to 10V MOSFET Gate Drivers
- Compatible with Logic-Level or Standard-Threshold NMOS
- 500 Watts Output Power Capable with a Single Device
- Fixed Synchronizable Operating Frequency from 50kHz to 600kHz
- Output Voltage Disconnect from VIN During Shutdown
- Adjustable Soft-Start
- ±1% Reference Voltage Accuracy over -40°C to 125°C
For more information on the LTC3777 Buck-Boost Controller, visit the Analog Devices Website at
Linear Technology LTC3777 product page
The company's Web site address is www.analog.com.
[Reprinted with kind permission from Analog Devices - Release Date: 12th February, 2018]