An e-ink panel such as the one linked below is 3.3V and refresh power is 10.5 mW typical. No problem there.
https://www.waveshare.com/wiki/2.13inch_e-Paper_HAT+
I have measured a Pico running using the 12 MHz XOSC at 2-3 mA (VUSB) ballpark. No USB, no PLLs. So VSYS 3V will need 5 mA or so. SLEEP is 0.8 mA (VUSB) while DORMANT is 1.3 mA (VUSB). Better sleep or go dormant most of the time, but the timer operation power will be substantial.
If you look for CR2032 discharge curves, the first image from a Google search shows a capacity of about 150 mAh for 3.0 mA continuous drain (versus the usual quoted 240 mAh -- for 0.5 mA). But I have an old Energizer CR2032 datasheet that gives about 230 mAh for pulsed drain discharge 6.8 mA / 2.7V / 2 sec pulses / 12 times a day. So effective CR2032 capacity will probably be less than 150 mAh. Can work I guess, but maybe marginal -- it will be hard on the CR2032.
Pico 2 has 10 uA sleep, that will work better. Pico doesn't have very low power sleep. Use Pico like this for a long-term use gizmo and you'd need loads and loads of CR2032 batteries.
https://www.waveshare.com/wiki/2.13inch_e-Paper_HAT+
I have measured a Pico running using the 12 MHz XOSC at 2-3 mA (VUSB) ballpark. No USB, no PLLs. So VSYS 3V will need 5 mA or so. SLEEP is 0.8 mA (VUSB) while DORMANT is 1.3 mA (VUSB). Better sleep or go dormant most of the time, but the timer operation power will be substantial.
If you look for CR2032 discharge curves, the first image from a Google search shows a capacity of about 150 mAh for 3.0 mA continuous drain (versus the usual quoted 240 mAh -- for 0.5 mA). But I have an old Energizer CR2032 datasheet that gives about 230 mAh for pulsed drain discharge 6.8 mA / 2.7V / 2 sec pulses / 12 times a day. So effective CR2032 capacity will probably be less than 150 mAh. Can work I guess, but maybe marginal -- it will be hard on the CR2032.
Pico 2 has 10 uA sleep, that will work better. Pico doesn't have very low power sleep. Use Pico like this for a long-term use gizmo and you'd need loads and loads of CR2032 batteries.
Statistics: Posted by katak255 — Fri Sep 27, 2024 6:36 am