This reference design automatically provides back-up voltages to an E-Meter during a power interruption. While the input voltage is between 10 V to 12 V, two buck controllers (TPS62147, TPS62173) generate 3.9 V at 2 A and 5 V at 150 mA. An optional synchronous boost generates 3.3 V at 50 mA. A discrete charge circuit charges a supercapacitor with a constant current up to an adjustable voltage of 2.7 V. When the input voltage fails, a synchronous boost takes over and boosts the supercap voltage to 3.9 V. The supercap capacitance and voltage defines the energy, which is available for the backup. The design enables a stable backup output of 3.9 V at 200 mA for about 70 s until the output voltage drops.
| Output voltage options | PMP30528.1 | PMP30528.2 | PMP30528.3 | PMP30528.4 |
|---|---|---|---|---|
| Vin (Min) (V) | 10 | 10 | 10 | 10 |
| Vin (Max) (V) | 12 | 12 | 12 | 12 |
| Vout (Nom) (V) | 5 | 3.3 | 3.9 | 3.9 |
| Iout (Max) (A) | .15 | .05 | 2 | 2 |
| Output Power (W) | .75 | .165 | 7.8 | 7.8 |
| Isolated/Non-Isolated | Non-Isolated | Non-Isolated | Non-Isolated | Non-Isolated |
| Input Type | DC | DC | DC | DC |
| Topology | Buck- Synchronous | Buck- Synchronous | Buck- Synchronous | Buck- Synchronous |
A fully assembled board has been developed for testing and performance validation only, and is not available for sale.
Download ready-to-use system files to speed your design process.
Test results for the reference design, including efficiency graphs, test prerequisites and more
Detailed schematic diagram for design layout and components
Complete listing of design components, reference designators, and manufacturers/part numbers
Detailed overview of design layout for component placement
Files used for 3D models or 2D drawings of IC components
Design file that contains information on physical board layer of design PCB
PCB layer plot file used for generating PCB design layout
Includes TI products in the design and potential alternatives.
| Type | Title | Date | ||
|---|---|---|---|---|
| * | Test report | Supercapacitor backup power supply for E-Meters reference design | Mar. 06, 2019 | |
| More literature | A supercapacitor and battery backup power-supply design PPT | Dec. 02, 2021 | ||
| More literature | Supercap last gasp failsafe power for RF comunications in E-Meters | Jan. 27, 2019 |
Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.
If you have questions about quality, packaging or ordering TI products, see TI support.