The LTM4632 from Linear Technology is a triple-output µModule (power module) regulator for powering all three voltage rails of the new QDR4 and older DDR SRAM: VDDQ, VTT and VTTR (or VREF). Housed in a miniature LGA package measuring 6.25 mm x 6.25 mm x 1.82 mm, the LTM4632 can be soldered on the backside of the PCB. With one resistor and three capacitors it occupies only 0.5 cm² (dual-sided) or 1 cm² (single-sided).
Linear Technology's LTM4632 µModule regulator. Source: Linear TechnologyCapable of delivering 3 A VDDQ and ±3 A VTT, two LTM4632s in parallel can provide up to 6 A per rail for larger memory banks. For more than 6 A VDDQ, the LTM4632 can be configured with the LTM4630 to provide between 18 A and 36 A VDDQ for very large arrays of SRAMs. If VDDQ is already available, the LTM4632 can be configured to supply a two-phase single VTT output up to 6 A.
The LTM4632 can operate from a low-input supply of 3.3 V, as well as standard 5 V and 12 V inputs (up to 15 V). Each of the two output voltages (VDDQ and VTT) range from 0.6 V to 2.5 V. The third output is a low-noise 10 mA buffered output for VTTR of the SRAM. Applications include PCIe, cloud-based systems, RAID, video processing and networking using these SRAMs: DDR/DDR-II/DDR-III/DDR4/QDR/QDR-II/QDR-II+ and QDR4.
The LTM4632 is rated to operate from -40° C to 125° C. Pricing for 1,000 pieces starts at $7.35 each for the E-grade and $8.09 each for the I-grade.
