| gerber | ||
| library | ||
| .gitignore | ||
| ABS2 THRU ABS10 N1693 REV.A.pdf | ||
| AP63200-AP63201-AP63203-AP63205.pdf | ||
| ds-st-st-series.pdf | ||
| fp-lib-table | ||
| gerber.zip | ||
| LICENSE | ||
| power-test.kicad_pcb | ||
| power-test.kicad_pro | ||
| power-test.kicad_sch | ||
| power.kicad_sch | ||
| README.md | ||
| sym-lib-table | ||
| tlv1117.pdf | ||
power-test
Engineer Responsible for this Section: Willow Herron
Section README Authored By: Katherine Sarna
Datasheets:
- TLV1117-33 (LDO)
- ABS10 (Diode bridge rectifier)
- DST-5-36 (Transformer)
- SW_DPDT (Switches x2, 3A and 3B) - Additional component from KiCad library
- AP63205WU (Switching regulator)
Purpose: This is our board for power signals.
We picked a transformer (120 or 240 to 16 or 18 V)
We added a switching element to the transformer primary side in order to control whether it took in 240 or 120 V, which as a bonus makes the design compatible with different countires! We can switch between series and parallel configuration for line/neutral on the primary side, which changes whether we're using 240V or 120V. The output is in parallel to get out 18V. For component selection considerations, we picked a pretty beefy diode bridge, because we are pulling a decent amount of current from the transformer (0.5A at 18V). The diode bridge has to withstand that, so we went with the ADS10 (see the datasheet). This is to rectify the AC 18V signal to DC 18V, whic leaves us with a full bridge rectified sine wave signal (abs value of sine wave).
However, we want linear values, so to smooth out the ripple, we added a hefty 10mF cap (ceramic to improve thermal characteristics). The switch mode power supply (5V, see switching regulator datasheet) can take up to 40V. It takes in a voltage of about 18V, and gives out the regulated 5V we're after. The inductor-capacitor design on its output is whatever's in the data sheet for switched mode pwr supply (FIX). We fused this 5V output with polyfuse (which is a PTC, or positive temperature coefficient resistor; a temperature dependent resistor), so if we end up drawing too much current we won't fry any circuitry. This helps with any overheating or overcurrent issues that may arise, and so we don't get an open circuit. We then added the 3.3V LDO Vout to turn 5V into 3.3v (NOTE: 3.3V is only used for signal, not for power).
As far as routing considerations go, all high voltage lines had to be separated by (preferably) PCB dielectrics. It would be ideal to have these lines on different layers, so that is what we did! Since this is the power board, all signals had to be as big as possible; so we routed with planes instead of traces and aimed to make said planes as big as possible.