I'm going to power an Wemos D1 Mini board with one 18650 battery. i allready have HT7333 and MCP1700 LDO regulators that outputs 3.3V to Wemos D1 3.3V pin.
But max current outputs is 250mA. I have heard that the Wemos can peak around 500mA.
I want an regulator that can take 500mA peak.
I can't find regulators in the same package (TO92) and TO220 i think is too big. Som sugestions? Or can i just use HT7333 og MCP1700?
HT78XX series are 500mA.
Thanks. I have totally missed that.
AMS1117 - Output Current of 1A (datasheet).
Sorry but in my opinion it will not work. At best you will have about 0.3 volt head room when the battery is charged and a - headroom when it is being used. My recommendation is to use a SEPIC converter or two batteries in series.
I think that is a bad advice. Ams has >1V droput. Bad for battery driven devices when using one 18650 battery do give power to 3.3V D1 Mini.
HT7833 is my goto here.
I have used the HT7333 on an ESP32 with a single Lithium battery as the power source. It would reset when trying to use the WiFi.
With the HT7833 there was no reset.
The Wemos mini's on board regulator will provide sufficient current for its own use. No external regulator needed, unless you plan to power other devices also.
I have many wemos mini running from 10440 & 18650 size li-ion batteries, 3xAAA NiMH and li-po packs for quite some years with no issues.
Bit i want to drive it in best possible way with one 18650 cell. With a >1V voltage drop its not possible.
These peaks are extremely short and are smoothed out by the capacitors on the board. The typical average current is around 80mA
I agree that with such a voltage drop, the Wemos would not run from a li-ion battery. But what is causing this voltage drop in your circuit?
My wemos with Wifi enabled draws around 170mA when starting up it peaks at around 300mA measured with a slow multimeter so it can be higher.
Wemos runs perfectly with one 18650 battery. What do you mean?
Yikes! Maybe it's faulty? I imagine it would get very hot very quickly. Is there anything else connected to the Wemos?
Yes. Two pins is active. Temperature sensor and voltage sense on A0 with divider.
That circuit does not sound like it would add significantly to the current consumption. Can you measure the current drawn by the temp sensor and voltage sensor? What current does the Wemos draw when these components are disconnected?
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