Point of load (POL) converters are a popular choice for applications that require multiple power rails demanded by the latest generation of Microprocessors, DSP or FGPA. These complex core IC increasingly require sophisticated power schemes, than often demand a large number of higher current, low Voltage power supply rails. Providing all the required power supply rails using a multi-channel PMIC means the power must be routed around the PCB from a central point, which can result in poor output regulation and complicated PCB layouts. Using a PMIC also localises the heat dissipation which can be problematic for thermal management.
These problems can be overcome by deploying several Point of load (POL) DC/DC Converters instead of a single PMIC, with each DC/DC providing a one supply rail and locating these DC/DC Converter IC close to where the power is required on the PCB. The resulting shorter PCB track lengths helps to improve VOUT stability and reduces EMI. The systems heat dissipation can also be spread more evenly around the PCB, which improves thermal management.
Torex specialises in simple, cost-effective, POL DC/DC Converters and this article shown how they can be used in typical application.
Using Point of Load Micro DC/DC Converters to power a Microprocessor or FPGA.
|(1) Step-down DC/DC||XCL205/06||DC/DC with Integrated Inductor, PWM/PFM, 3MHz, 600mA|
|XCL211/12||DC/DC with Integrated Inductor, PWM/PFM, 2.4MHz, 2A|
|(2) RESET IC||XC6119||Low Iq, Release delay with external Cd|
(1) Step-down DC/DC for MPU / Memory / FPGA as POL
(2) Monitoring 5V input
(3) Start-up / Shutdown sequence
Typical PMIC Approach
Problems with using a PMIC
Point Of Load Approach:
Benefit of POL and TOREX proposal