- Wed Feb 01, 2023 3:24 pm
#95943
Dear community,
I’ve been trying to set up an ESP 12F based project and I have issues with the power. My goal is to use a rather flexible DC-DC converter (MC34063A) with an input voltage range between 3.0V and 40V. Additionally, I have a rectifier at the beginning (D2) to support AC. The schematics are below. Note: do not mind that it says 24V - this was just for my reference.
While assembling it, I am gradually testing the whole circuit with a lower voltage - 12V DC. The DC-DC converter works as the 3V3PWR LED light shines red. I also measured it with the multimeter - I get 3.3V between the 3V3 and GND. The odd and unwanted behavior I am observing is that as soon as I connect the ESP 12F to the 3V3 and GND, the red LED light (3V3PWR) gets significantly dimmer (voltage drop). Additionally, I can hear a high pitch noise coming from the DC-DC converter. This makes the whole thing useless.
Later on, I did realize that I forgot to include the 100nF and 10uF capacitors as suggested by the ESP 12F documentation and other forum posts. I tried to remedy this with a ceramic 100nF and an electrolytic of 10uF right on the power pins of the ESP (image below with only the ESP and related resistors on the board). This did not improve the situation anyhow.
Here are the measurements I performed:
I am at a complete loss here as to where my problem lies. Have I perhaps selected an unsuitable DC-DC converter? If so, what exactly is the part that is unsuitable?
I thank you all for reading this and considering helping me out.
Cheers!
I’ve been trying to set up an ESP 12F based project and I have issues with the power. My goal is to use a rather flexible DC-DC converter (MC34063A) with an input voltage range between 3.0V and 40V. Additionally, I have a rectifier at the beginning (D2) to support AC. The schematics are below. Note: do not mind that it says 24V - this was just for my reference.
While assembling it, I am gradually testing the whole circuit with a lower voltage - 12V DC. The DC-DC converter works as the 3V3PWR LED light shines red. I also measured it with the multimeter - I get 3.3V between the 3V3 and GND. The odd and unwanted behavior I am observing is that as soon as I connect the ESP 12F to the 3V3 and GND, the red LED light (3V3PWR) gets significantly dimmer (voltage drop). Additionally, I can hear a high pitch noise coming from the DC-DC converter. This makes the whole thing useless.
Later on, I did realize that I forgot to include the 100nF and 10uF capacitors as suggested by the ESP 12F documentation and other forum posts. I tried to remedy this with a ceramic 100nF and an electrolytic of 10uF right on the power pins of the ESP (image below with only the ESP and related resistors on the board). This did not improve the situation anyhow.
Here are the measurements I performed:
- - The voltage drops from 3.3V to 1.4V.
- The current drawn by the ESP at 1.4V is 93mA.
- The resistance between the SWE (#2) pin of the DC-DC converter and the ESP VCC is 2.8 Ohms.
I am at a complete loss here as to where my problem lies. Have I perhaps selected an unsuitable DC-DC converter? If so, what exactly is the part that is unsuitable?
I thank you all for reading this and considering helping me out.
Cheers!
