Differences

This shows you the differences between two versions of the page.

--- env_sensor [2015/12/06 17:54] – [Connect a SHT15] breaker27
+++ env_sensor [2015/12/12 14:30] – [Connect a button or switch] breaker27
@@ Line 79: / Line 79: @@
   - If you want to detect the botton / switch / pin state **immediately**, you need some sort of **permanent pull-up resistor** (assuming the button/... is connected against ground again). **Please note that the pull-up resistor only draws current if the button/... is currently active (pulling the level to low).**
     * If you use the internal resistor with its resistance of around 22 kOhm, it would draw about 135µA, which is a lot. This is only recommended if you power your device with a power supply (not batteries).
-    * The second option is to connect an external (physical) pull-up resistor of 1 MOhm to 10 MOhm (untested). One 1 MOhm pull-up (for one I/O pin) would draw around 3µA (at 3V battery voltage), so this is also noticeable compared to the sleep power consumption of around 1,2µA. Depending on your batteries, amount of I/O pins used as digital input and the percentage of the pin being pulled down by the button/..., you may try a risistor with a higher value like 10 MOhm.
+    * The second option is to connect an external (physical) pull-up resistor of 1 MOhm to 10 MOhm. One 1 MOhm pull-up (for one I/O pin) would draw around 3µA (at 3V battery voltage), so this is also noticeable compared to the sleep power consumption of around 1,2µA. Depending on your batteries, amount of I/O pins used as digital input and the percentage of the pin being pulled down by the button/..., you may try a risistor with a higher value like 10 MOhm.
 ===== Connect a SHT15 =====