{"thread":{"id":"0ve0JwhGsLJ0","title":"ESP32 deep sleep draws 8mA instead of 10uA?!?!","content":"Datasheet says about 10uA in deep sleep. I measure EIGHT MILLIAMPS. Battery lasted 9 days instead of the year I was bragging about!!\n\nesp_sleep_enable_timer_wakeup(600ULL * 1000000ULL);\nesp_deep_sleep_start();\n\nIt definitely sleeps, the wifi stops and current drops from 80mA. Board is one of those cheap devkits from the usual place. Am I missing some magic setting","category":"help","status":"resolved","author":"h4nk","createdAt":"2026-09-22T15:06:14.234Z","updatedAt":"2026-11-04T02:19:14.234Z","expiresAt":null,"replyCount":12,"pinned":false,"locked":false,"solved":true,"tags":["esp32","hardware"],"lastNumber":13,"postCount":13,"editedAt":null,"acceptedReplyId":"9Q0VEA0I7wLc","thanks":0,"thanked":false},"replies":[{"id":"rPwZZqKuenkE","content":"You're measuring the board, not the chip. Those devkits have a USB-serial bridge, a linear regulator with a fat quiescent current, and a power LED. All of it stays on.","author":"kris !LryyDLF-","createdAt":"2026-09-22T15:29:14.234Z","number":2,"removed":false,"accepted":false,"editedAt":null,"thanks":0,"thanked":false},{"id":"XPdcDOtEO63O","content":"The LED! ok I can desolder the LED","author":"h4nk","createdAt":"2026-09-22T15:45:14.234Z","number":3,"removed":false,"accepted":false,"editedAt":null,"thanks":0,"thanked":false},{"id":"IjbSXGp_dBQE","content":"That'll get you maybe 2mA back. CP2102 and the regulator are the rest. If you want the real number you need a bare module and a low Iq regulator.","author":"kris !LryyDLF-","createdAt":"2026-09-22T16:00:14.234Z","number":4,"removed":false,"accepted":false,"editedAt":null,"thanks":3,"thanked":false},{"id":"JBdXZMbp0VAE","content":"For what it's worth I gave up and used a bare WROOM-32 on a small carrier with an MCP1700. It's fine for a garage sensor.","author":"dan_r","createdAt":"2026-09-22T20:59:14.234Z","number":5,"removed":false,"accepted":false,"editedAt":null,"thanks":2,"thanked":false},{"id":"6sMfKRqfbGUj","content":"Parts came!! Bare module + MCP1700. Now reading 210uA. Better but not 10!!","author":"h4nk","createdAt":"2026-09-24T04:11:14.234Z","number":6,"removed":false,"accepted":false,"editedAt":null,"thanks":0,"thanked":false},{"id":"kHOdMahvWZRh","content":"What else is on the rail? Sensor? Voltage divider for the battery?","author":"kris !LryyDLF-","createdAt":"2026-09-24T04:28:14.234Z","number":7,"removed":false,"accepted":false,"editedAt":null,"thanks":0,"thanked":false},{"id":"lY2KIH2nMCRm","content":"DHT22 and a divider, 10k + 10k for battery voltage. Oh no.","author":"h4nk","createdAt":"2026-09-24T04:41:14.234Z","number":8,"removed":false,"accepted":false,"editedAt":null,"thanks":0,"thanked":false},{"id":"9Q0VEA0I7wLc","content":"There you go. A 20k divider on a 4V cell is 200uA all by itself. Go to 1M + 1M and put 100nF across the bottom resistor so the ADC has something to sample. And power the DHT from a GPIO, or a P-channel switch, so it's off during sleep.","author":"kris !LryyDLF-","createdAt":"2026-09-24T04:46:14.234Z","number":9,"removed":false,"accepted":true,"editedAt":null,"thanks":4,"thanked":false},{"id":"FtoeDX0eZ_zy","content":"Also how are you measuring? A multimeter on the uA range has a big burden voltage. Can brown out at wake-up when it pulls 200mA through that range. If it reboots in a loop on the meter and not on the bench supply, that's why.","author":"zp_indirect","createdAt":"2026-09-24T05:24:14.234Z","number":10,"removed":false,"accepted":false,"editedAt":null,"thanks":0,"thanked":false},{"id":"EeUttJikCqCg","content":"GOT IT. 14uA with the 1M divider and DHT on a GPIO!!! kris you are a legend. Marking this solved. Burden voltage was also real, it kept resetting until I shorted the meter during wake.","author":"h4nk","createdAt":"2026-09-25T02:23:14.234Z","number":11,"removed":false,"accepted":false,"editedAt":null,"thanks":0,"thanked":false},{"id":"tQx3JvLAVyJG","content":"Nice. Post the numbers after a month on the battery, I'd like to see how close it gets to the sum.","author":"kris !LryyDLF-","createdAt":"2026-09-25T02:36:14.234Z","number":12,"removed":false,"accepted":false,"editedAt":null,"thanks":0,"thanked":false},{"id":"AlRgSXYhhF-p","content":"Few weeks late, sorry. Anyone doing this on a newer part should look at the C3, deep sleep is about 5uA and the same board rules apply. Devkit numbers are meaningless, as above.","author":"sparrow","createdAt":"2026-11-04T02:19:14.234Z","number":13,"removed":false,"accepted":false,"editedAt":null,"thanks":0,"thanked":false}]}