I have not yet build following circuit: enter image description here

Circuit in high performance needs 5V 1.7A (measured). I have source which is powerbank with 16 000 mAh. Outputting via ports: USB-C 5V/3A, USB-A 5V/3A, Micro-USB 5V/2A. Also it is important to notice that powersource which is powerbank is 1 meter away from circuit board (image above). I will connect circuit board to powerbank via USB-C connector (U1).

Circuit description: LED: 5V/1.6A powering APA102 85 led strips C6: 100nF P5: green LED R13: 1k ohm C5: 10uF D2: 1N4007G U2: ESP32

What I am asking is how to make ESP32 (U2) uninterrupted from power. If it does then controller will not send data to LED strips.

Operating temperature in cold outdoor environment - mountains.

My previous version had 1.5mm copper wire to power circuit via DC jack with issue while rotating DC jack power is lost for few ms (my eye couldn't notice but data sending stoped immediately) which make ESP32 freeze. USB-C should be able to deliver enough power via 4 pins.

Question is that: Does circuit contains everything? Do you suggest to add something? I don't understand very much how to make circuit stable.

  • \$\begingroup\$ @Bimpelrekkie my apologies. Post updated \$\endgroup\$ – user1085907 Feb 8 at 21:55
  • \$\begingroup\$ while rotating DC jack power is lost for few ms To make the circuit more robust for that, add a larger capacitor between Vin and Ground. I suggest using a 470 uF capacitor. Beware that such large capacitors have a polarity (+ and -). The capacitor can shortly provide power when the connection to the power source is lost for a few ms. Note that all batteries work much worse when they're cold so don't expect that you can use all energy from the power bank under cold conditions. \$\endgroup\$ – Bimpelrekkie Feb 8 at 22:01
  • \$\begingroup\$ the micro-usb port is very probably for charging, not discharging. \$\endgroup\$ – Hearth Feb 8 at 22:08
  • \$\begingroup\$ @Hearth u are correct. Forgot to mention that. Anyway I will use USB-C on powerbank \$\endgroup\$ – user1085907 Feb 8 at 22:31

The Esprino devkit already has >100uF of capacitors in the power input. I'd recommend separating the power for your esprino from the led strips.


simulate this circuit – Schematic created using CircuitLab

This way the LEDs strip won't suck power out of the esprino during short power interruptions.

The SS14 is a low forward drop diode, and the capacitor will power the LDO regulator on the ESP DevKit for some time. The diodes on the output stops the Esprino attempting to power the led strip through the ESD protection diodes when the LED strip loses power.

  • \$\begingroup\$ Quick question. Do you recommend 1N4148 (200mA - DO-35 package) or 1N4148 (150mA - SOD-123 package). I would choose second option, is it correct? \$\endgroup\$ – user1085907 Feb 9 at 17:20
  • \$\begingroup\$ Looking carefully your maximum/minimum Low and High Voltages are 0.3VDD and 0.7VDD, and the current is negligible as they think only a 570k pull up is needed. So your diode needs to have Vf < 1.5V, and If > 0.5mA. Almost any signal diode at all will work, it's not a particularly taxing application. I suggested 1N4148 as they're the most common signal diode ever. Either of your choices is fine and has more than 200 times the needed If. \$\endgroup\$ – james Feb 9 at 17:42
  • \$\begingroup\$ Just for sure.. this diode should work right? datasheet.lcsc.com/szlcsc/… \$\endgroup\$ – user1085907 Feb 9 at 17:56
  • \$\begingroup\$ They look fine. \$\endgroup\$ – james Feb 9 at 18:51

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