36A single/18A dual µModule PMBus regulator current shares to 144A

December 04, 2015 // By Graham Prophet
LTM4677 is a dual 18A or single 36A µModule (power module) step-down DC/DC regulator with PMBus serial digital interface for autonomous digital power system management. The digital interface enables system designers and remote operators to control and supervise a system’s power condition and consumption via an I²C bus with READ and WRITE commands.

The LTM4677 has applications in optical data transport systems, datacom and telecom switches and routers, industrial test equipment, robotics, RAID and enterprise systems where the cost of electricity, cooling and maintenance are critical and must be continuously and precisely measured. It offers ± 2.5% current read back accuracy, ±0.5% maximum DC output voltage error over temperature and accepts input voltage of 4.5V to 16V; output voltages: 0.5V to 1.8V.

The LTM4677 is comprised of EEPROM, I ²C interface, dual DC/DC controller, power MOSFETs, inductors and supporting components. Its two 18A outputs can current share to provide up to 36A single output. As many as four LTM4677 devices can be multi-phased to share current up to 144A output. An advantage of the LTM4677 is its ability to current share with non-PMBus interfaced µModule regulators such as the 26A LTM4620 and 36A LTM4630.

Lower power versions of the LTM4677, the LTM4675 (9A, 9A) and the LTM4676A (13A, 13A), are pin compatible with the LTM4677 and are 100% functional alternatives during system prototyping, eliminating the need to change circuit board layout.

The LTM4677 has fast, dual analogue control loops, precision mixed-signal circuitry and is housed in a 16 x 16 x 5.01 mm BGA (ball grid array) package. Its internal operating temperature range is from -40°C to 125°C. 1,000-piece price is $39.60 each.

Linear Technology; www.linear.com/product/LTM4677