Analog Angle Article

Switching DC/DC uModules strive to yield LDO-class low noise

Milpitas, Calif—Seeking to resolve the dilemma between the efficiency of a switching regulator and the low-noise attribute of an LDO, the LTM4606 and LTM4612 uModule dc/dc regulators from Linear Technology Corp. meets stringent EMI specifications. The fully encapsulated modules include requisite inductor, MOSFETs, regulator IC, and compensation network, as a single land-grid array (LGA) drop-in unit measuring 15 x 15 mm, with 2.8 mm height.

By controlling the slew rate of the MOSFET gate drive, adding π -filters, shielding the inductor, using careful layout techniques and appropriate components, the modules have been demonstrated to provide highest performance and a stable eye pattern in noise-sensitive applications such as multi-Gbps SERDES and RocketIo designs. Due to their low radiated and conducted noise, they have also achieved CISPR22 Class B certification (stricter than Class A) from an independent lab; no ferrite beads or other external components are needed to meet EMI standards

The LTM4606 accepts a 4.5-to-28 Vdc input, and provides an output from 0.6to 5 V, at up to 6 A. The similar LTM4612 accepts a 5-to-36 V input with output of 3.3 to 15 V at 5 A. Output ripple is also low: for the LTM4606, for example, with input of 5 V, output of 1 V at 6 A, the observed ripple is less than 3 mV over a 300-MHz bandwidth.

Price and availability : The pin-compatible modules are specified for -40 °C to +125 #176;C, and version which is characterized for -55 #176;C is also available. Pricing (1000 pieces) is $16.50 for the LTM4606EV and $19.89 for the LTC4612EV.—by Bill Schweber.

0 comments on “Switching DC/DC uModules strive to yield LDO-class low noise

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.