Search found 30 matches

by trustmiao
Wed Sep 26, 2018 6:33 am
Forum: Hardware
Topic: with ESP-NOW, it brown out with 500ma max current ldo ht7833
Replies: 6
Views: 1964

Re: with ESP-NOW, it brown out with 500ma max current ldo ht7833

Sorry for late reply, just back from national holiday. We have got the 1uf between vin-gnd, 2.2uf between vout-gnd. We left a jumper to bypass the HT7833 for testing, as the skech below. 微信图片_20180926140634.png We are using ESP-WROOM-32. Vout then connects to 3v3 and all the sensor's vcc, while at t...
by trustmiao
Wed Sep 19, 2018 2:32 am
Forum: Hardware
Topic: with ESP-NOW, it brown out with 500ma max current ldo ht7833
Replies: 6
Views: 1964

with ESP-NOW, it brown out with 500ma max current ldo ht7833

We try to design an application powered by one 14500, 3.7 lipo. At early tests, we prefer ht7833 to ams1117, as the drop-out voltage of ams1117 is up to 1.3v. We tried as many ldo regulator as possible and finally choose ht7833. However, three of the test boards all failed after we upload the code. ...
by trustmiao
Wed Sep 19, 2018 2:02 am
Forum: Hardware
Topic: Esp32 Devkit v1 PCB Eagle library
Replies: 1
Views: 5992

Re: Esp32 Devkit v1 PCB Eagle library

nice one
by trustmiao
Fri Aug 24, 2018 10:36 am
Forum: ESP32 Arduino
Topic: read from i2c failed 80 percent chance, after couple reboot it works
Replies: 7
Views: 1555

read from i2c failed 80 percent chance, after couple reboot it works

I am trying to connect esp32 to a BNO080 through i2c. The code and bno080 have been tested successfully with Arduino, and there is something weird happening when move to esp32. The bno080 is connected to 21 22 with 10k pullup from 3.3v. and I am sure the code is fine. but, only one in five times I r...
by trustmiao
Thu Aug 09, 2018 10:59 am
Forum: Hardware
Topic: Battery power from 1 LIPO and 3v3 regulator LDO can't turn ESP32 on
Replies: 10
Views: 2768

Re: Battery power from 1 LIPO and 3v3 regulator LDO can't turn ESP32 on

That will definitely be an option, but not ideal one, as dc-dc's efficiency is by average 70-80%, a lot of waste. Not with good quality switching boost converter that has 70-90% efficiency depending on IC. It will convert to nice output depending on how strong current your lipo can provide. and you...
by trustmiao
Thu Aug 09, 2018 10:56 am
Forum: Hardware
Topic: Battery power from 1 LIPO and 3v3 regulator LDO can't turn ESP32 on
Replies: 10
Views: 2768

Re: Battery power from 1 LIPO and 3v3 regulator LDO can't turn ESP32 on

Erm, no, provided that the LiIon can provide the 500mA spikes (most can do this) and you don't feed any other really noisy things from it, there's no need for such an outrageously large capacitor. The datasheet suggests an 1uF cap on the input and a 2.2uF cap on the output. I think, for the output,...
by trustmiao
Wed Aug 08, 2018 3:39 pm
Forum: Hardware
Topic: Battery power from 1 LIPO and 3v3 regulator LDO can't turn ESP32 on
Replies: 10
Views: 2768

Re: Battery power from 1 LIPO and 3v3 regulator LDO can't turn ESP32 on

- HT7333 chips can only output 250mA. You need at least 500mA to be able to provide peak power for the RF bits in the chips. - The dropout voltage of this chip can easily reach >1V (@250mA) which means the ESP32 and the flash chip will only get 2.7V. While the ESP32 likely is OK with it, this brown...
by trustmiao
Wed Aug 08, 2018 3:32 pm
Forum: Hardware
Topic: Battery power from 1 LIPO and 3v3 regulator LDO can't turn ESP32 on
Replies: 10
Views: 2768

Re: Battery power from 1 LIPO and 3v3 regulator LDO can't turn ESP32 on

Deouss wrote:I remember having similar issues - try connecting lipo to 5V boost converter and then connect to 5V input plug
That will definitely be an option, but not ideal one, as dc-dc's efficiency is by average 70-80%, a lot of waste.
by trustmiao
Tue Aug 07, 2018 11:45 am
Forum: Hardware
Topic: Battery power from 1 LIPO and 3v3 regulator LDO can't turn ESP32 on
Replies: 10
Views: 2768

Re: Battery power from 1 LIPO and 3v3 regulator LDO can't turn ESP32 on

Thx buddy, HT7833 is on the way, i will post back after some tests.
by trustmiao
Mon Aug 06, 2018 3:54 pm
Forum: Hardware
Topic: Battery power from 1 LIPO and 3v3 regulator LDO can't turn ESP32 on
Replies: 10
Views: 2768

Battery power from 1 LIPO and 3v3 regulator LDO can't turn ESP32 on

We try to power ESP32 with one LIPO battery, but we can't get it work with voltage regulator. https://i1.wp.com/randomnerdtutorials.com/wp-content/uploads/2016/12/ESP32_dev_board_pinout.jpg Power is connected to 3.3v and GND on the top left and top right. We connect a LED, firmware is basically blin...

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