Analog Devices
Regulator with digital power system management
The LTM4686 from Power by Linear, a dual 10A or single 20A ultrathin step-down µModule regulator with a PMBus interface housed in a 16×11.9×1.82mm LGA package has been announced by Analog Devices.
The 1.82mm package height allows the LTM4686 to be placed on a PC board very close to its load such as an FPGA or ASIC, while sharing one heat sink covering both low-profile packages. The ultrathin package allows the LTM4686 to be mounted on the backside of a PCB, freeing topside space for components such as memory and transceiver ICs. This makes the LTM4686 suitable for height-restricted applications such as rack-mounted telecom switches and routers, raid systems, and test and measurement equipment.
The PMBus interface enables users to measure and alter key power parameters such as voltage, load current and temperature. Users can also program sequencing, fault thresholds and responses via PMBus, storing values and fault log data in the onboard EEPROM.
The LTM4686 operates from 4.5 to 17V and the LTM4686-1 from 2.375 to 17V input supplies. These modules regulate an output from 0.5 to 3.6V with ±0.5% maximum DC output error over temperature, -40 to +125°C. They deliver 80% efficiency at 12VIN to 1.0VOUT at a full load condition. It can deliver 18A from a 5VIN to a 1VOUT at 85°C ambient with 400LFM air flow. Current mode control enable operation in a parallel configuration, to deliver increased output current. Its internal switching frequency is settable from 250kHz to 1MHz and can be synchronized to an external clock from 250kHz to 1MHz for noise-sensitive applications.
The LTM4686 configurable offers protection features, including overvoltage and undervoltage, overcurrent and overtemperature. If a fault occurs, data is saved automatically to the EEPROM, and the fault log can be retrieved over an I2C interface, where it can then be analyzed. To evaluate the performance of the LTM4686, the LTpowerPlay GUI DC1613 USB-to-PMBus converter VDC2086 programing adapter and demo kits are available.
