DC1184A

Evaluation Board, Ltc3860 Buck Converter

The demonstration board is a dual output voltage mode synchronous buck converter featuring LTC3860EUH device. The LTC3860EUH is a dual, PolyPhase synchronous step down switching regulator controller for high current distributed power systems, digital signal processors and other telecom and industrial DC to DC power supplies. This demonstration board provides two outputs of 1.2V/25A and 1.8V/25A from an input voltage of 10V to 14V at a switching frequency of 500KHz. The power stage consists of Renesas R2J20602NP which is a tristate PWM compatible 8mm x 8mm DrMOS and a 0.47µH 13.2mm x 12.8mm iron powder type inductor from Wurth. An onboard LT1616 buck regulator provides the 5V bias for the LTC3860 and the DrMOS. The demo board uses a high density, two sided drop in layout. The power components, excluding the bulk output and input capacitors, fit within a 1.5inch x 1.25inch area on top layer. The control circuit resides in a 0.75inch x 0.75inch area on the bottom layer.

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Operates with power blocks, DRMOS or external gate drivers and MOSFETs

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Differential amplifier for remote sensing VOUT1 which is setup for 1.2V

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Optional components for single output dual phase operation

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CLKIN pin for synchronization to an external clock

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TRACK/SS pins for external coincident rail tracking

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RUN pins and PGOOD pins for each phase

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For each phase, optional footprints for an LTC4449 gate driver and two top FETs and two bottom FETs

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87.8% efficiency at VOUT1 = 1.2V

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91.0% efficiency at VOUT2 = 1.8V

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Output voltage tracking capability