TB429

The complete schematic of EL7515 demo board is shown in Figure 1. With different components stuffed, this demo board can easily be configured into the applications shown in this technical brief. The standard demo board being sent out is the complete 5V to 12V converter shown in Figure 2, which occupies less than 0.4 in2 area with  components on top side only. Layout diagrams are given at the end of this document.

1. VIN = 2V-5.5V. Can be higher with higher voltage rated C1
2. VO = 12V. Can be set according to the following formula:

where VFB is shown in the VFB vs VDD curve.

3. IO - up to 600mA depending on input voltage, provided that diode and inductor can handle the corresponding currents (refer to data sheet for the chart)

4. Switching frequency - can be set by R3

5. R4 can be 10 - 51 if VO is less than 10V. If VO is larger than 12V, it can be calculated by:

where IDD is a function of switching frequency, as shown in the IDD vs FS curve.