diff --git a/doc/mlx90632/media/datasheet_refresh_rate_vs_noise.png b/doc/mlx90632/media/datasheet_refresh_rate_vs_noise.png new file mode 100644 index 0000000..62419f4 Binary files /dev/null and b/doc/mlx90632/media/datasheet_refresh_rate_vs_noise.png differ diff --git a/doc/mlx90632/refresh_rate_update.md b/doc/mlx90632/refresh_rate_update.md index 40c169e..de7de19 100644 --- a/doc/mlx90632/refresh_rate_update.md +++ b/doc/mlx90632/refresh_rate_update.md @@ -1,3 +1,19 @@ +# Procedure to update the refresh rate + +## Intro + +The refresh rate defines the integration time the ADC gets alotted for it's acquisition of the signals. +So the slower the refresh rate, the longer the integration time, and consequently the lower the noise on the reading will be. +The refresh rate can be programmed between 64 Hz and 0.5Hz meaning that the integration time can be set in a ragne from 16ms to 2 seconds. + +See datasheet for the noise impact: (https://melexis.com/mlx90632) +![datasheet_refresh_rate_vs_noise.png](media/datasheet_refresh_rate_vs_noise) + + +## The process + +The refresh rate setting resides in the EEPROM of the MLX90632. Therefore it is mandotory to select one refresh rate for your application and stick with it, as the re-programming will get you fast through the EEPROM erase/write cycles. + Below is a listing from the I2C Stick console where I took one MLX90632, starting with the default refresh rate, then I erase both 24E1 and 24E2 addresses, then I write the new content. The `<-` sign indicates that what I entered in the console, while the `->` sign indicates the answer from the I2C Stick (and thus indirectly what MLX90632 answers on the I2C bus). @@ -35,7 +51,6 @@ As mode is bit 1 & 2, the mode was 3, and it turns out all other bits were at ze The next command below, is `unlock`. See datasheet: (https://melexis.com/mlx90632) -image.png ![datasheet_unlock_eeprom_customer.png](media/datasheet_unlock_eeprom_customer.png) It is equivalent of writing 554C to address 3005. Note: you cannot read this to verify, and it will last only one write operation.