Analog Devices Inc. has announced the Power by Linear™ LT8708/-1, a 98% efficient bidirectional buck-boost switching regulator controller that operates between two batteries that have the same voltage, which are ideal for redundancy in self-driving cars.
The LT®8708-1 is a high performance buck-boost switching regulator controller that is paralleled with the LT8708 to add power and phases to an LT8708 system. The LT8708-1 always operates as a slave to the master LT8708 and has the capability of delivering as much current or power as the master. One or more slaves can be connected to a single master, proportionally increasing power and cur-rent capability of the system.
The LT8708-1 has the same conduction modes as LT8708, allowing the LT8708-1 to conduct current and power in the same direction(s) as the master. The master controls the overall current and voltage limits for an LT8708 mul-tiphase system, and the slaves comply with these limits.
LT8708-1s can be easily paralleled with the LT8708 by connecting four signals together. Two additional current limits (forward VIN current and reverse VIN current) are available on each slave that can be set independently.
- Operates with Two Batteries with the Same or Different Voltages
- Synchronous Rectification: Up to 98% Efficiency
- Delivers up to several Kilowatts with Multiphase Operation
- Single Inductor Allows VIN Above, Below, or Equal to VOUT
- Six Independent Forms of Regulation
- VIN Current (Forward & Reverse)
- VOUT Current (Forward & Reverse)
- VIN & VOUT Voltage
About LT8708 System
- Forward & Reverse Discontinuous Conduction Mode Supported
- Supports MODE & DIR Pin Changes While Switching
- VIN Range 2.8V (Need EXTVCC > 6.4V) to 80V
- VOUT Range: 1.3V to 80V
- Available in 40-Lead 5mm × 8mm QFN with High Voltage Pin Spacing
The LT®8708 is a high performance buck-boost switching regulator controller that operates from an input voltage that can be above, below or equal to the output voltage. Features are included to simplify bidirectional power conversion in battery/capacitor backup systems and other applications that may need regulation of VOUT, VIN, IOUT, and/or IIN. Forward and reverse current can be monitored and limited for the input and output sides of the converter. All four current limits (forward input, reverse input, forward output and reverse output) can be set independently using four resistors on the PCB.
The MODE pin can select between discontinuous conduc-tion mode (DCM), continuous conduction mode (CCM), hybrid conduction mode (HCM) and Burst Mode® operation. In combination with the DIR (direction) pin, the chip can be configured to process power only from VIN to VOUT or only from VOUT to VIN. With a wide 2.8V to 80V input and 1.3Vto 80V output range, the LT8708 is compatible with most solar, automotive, telecom and battery-powered systems.