1.8mm profile, 3-A regulator module for PCIe, ATCA, microTCA cards

December 02, 2014 // By Graham Prophet
LTM4623 is a 3A µModule (micromodule) step-down regulator in a 1.8-mm profile LGA package with a 6.25 x 6.25mm footprint. With solder paste, the package height is less than 2mm, meeting the height restrictions of many PCIe (PCI Express), Advanced Mezzanine Cards (AMC) for AdvancedTCA carrier cards in embedded computing systems.

The small size and low height allow the LTM4623 to be mounted on the backside of the PCB, freeing space on the topside. The LTM4623 operates from 4V to 20V input supplies and precisely regulates an output voltage from 0.6V to 5.5V with 1.5% maximum total DC output voltage error, Application examples include ultra-dense data storage, gateway controllers and 40 Gbps to 100 Gbps network equipment.

The LTM4623 solution fits in a 0.5 cm² dual-sided PCB or occupies less than 1 cm² on a single-sided PCB. The circuit only requires one input capacitor and one output capacitor, a resistor to set VOUT, and a small capacitor for VOUT tracking and soft-start. With an auxiliary 5V bias, the LTM4623 operates from input supplies as low as 2.375V. The operating efficiency for converting 12 VIN to 1.5 VOUT and 3.3 VOUT at 3A is 80% and 88%, respectively. Power loss for 12 VIN to 1.5 VOUT is 1.1W, resulting in a 24°C rise in junction temperature. It includes overvoltage, overcurrent and overtemperature protection. The LTM4623 is rated for operation from -40°C to 125°C and is priced at $6.05 (1,000)

Linear Technology; www.linear.com/product/LTM4623