TI introduce 20V DC-DC synchronous buck controller
Texas Instruments introduce the first analog DC-DC step-down controller with remote bipolar junction transistor temperature-compensated inductor current sensing. Minimising the total solution footprint in high-power POL conversion, the LM27403 offers efficiency greater than 95% from a 12-V input at 25 A of output current.
Featuring an optimizes solution size, the 20-V LM27403 DC-DC synchronous buck controller provides fast transient response in communications infrastructure, industrial, medical and power module applications. Used with TI's WEBENCH online design tool, the LM27403 simplifies DC-DC conversion and speeds the design process.
Using a low-cost BJT to measure real-time temperature shifts, the temperature-compensated inductor DC resistance sensing improves the current limit accuracy to 10 percent over temperature. This allows the LM27403 to maintain a consistent current limit threshold across the operating temperature range. The current limit accuracy over temperature results in a smaller DC-DC converter footprint that reduces inductor over-design and allows for the use of smaller and lower-cost inductors.
The LM27403 provides a complete dynamic voltage solution when designed together with TI’s LM10011 voltage identification interface controller and 30-V CSD87350Q5D synchronous buck NexFET Power Block MOSFET to adjust the core voltage of a VID-enabled processor, such as TI's TMS320C6000 power-optimized DSPs and KeyStone based multicore DSPs.
Key features & benefits:
- Wide 3-V to 20-V input voltage range converts 3.3-V, 5-V and 12-V input voltage rails to point-of-load as low as 0.6 V with one-percent accuracy,
- 30-ns minimum on-time allows higher switching frequencies at lower duty cycles, providing greater scalability and smaller solution size,
- 15-ns adaptive dead-time control provides higher efficiency in high frequency operation, reducing power consumption,
- Output voltage remote sensing gives improved load regulation in high current applications.
Availability, packaging and pricing
The LM27403 synchronous buck controller is available in volume now, priced at US$1.20 in 1,000-unit quantities. The DC-DC controller is offered in a 4-mm by 4-mm by 0.8-mm, 24-pin PowerPad WQFN package.