Linear Technology introduced the LTM4632 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, lightweight, ultrathin LGA package (6.25mm x 6.25mm x 1.82mm), the LTM4632 can be soldered on the backside of the PCB, and with one resistor and three capacitors it occupies only 0.5cm² (dual-sided) or 1cm² (single-sided). Capable of delivering 3A VDDQ and ±3A VTT (=1/2*VDDQ) two LTM4632s in parallel can provide up to 6A per rail for larger memory banks. For more than 6A VDDQ, the LTM4632 can be configured with the LTM4630 to provide between 18A and 36A 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 6A.
The LTM4632 can operate from a low input supply of 3.3V, as well as standard 5V and 12V inputs (up to 15V). Each of the two output voltages (VDDQ and VTT) range from 0.6V to 2.5V. The third output is a low noise 10mA 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 contains a triple output DC/DC regulator, divide by 2 circuit, power switches, inductors and support components in a compact, ultrathin package. The LTM4632 is rated for operation from -40°C to 125°C. 1,000-piece pricing starts at $7.35 each for E-grade and $8.09 each for I-grade.
Summary of Features: LTM4632
Complete DDR/QDR4 Memory Power Solution in 1cm² (Single-Sided PCB) or 0.5cm² (Dual-Sided PCB)
3A VDDQ + 3A VTT or Dual Phase Single 6A VTT
Wide Input Voltage Range: 3.6V (With VIN Tied to INTVCC) to 15V
0.6V to 2.5V Output Voltage Range
±1.5%, ±10mA Buffered VTTR = VDDQ/2 Output
External Frequency Synchronization
Ultrathin 6.25mm x 6.25mm x 1.82mm LGA Package