diff options
Diffstat (limited to 'center_fw/notes')
| -rw-r--r-- | center_fw/notes | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/center_fw/notes b/center_fw/notes new file mode 100644 index 0000000..99a8b2a --- /dev/null +++ b/center_fw/notes @@ -0,0 +1,10 @@ +Pink led strip details: +at Vcc = 11.88V, the voltage across the 68R dropper resistor is 2.06V. +Thus, I is 30mA, the forward voltage of the LEDs is 9.82V/3 = 3.27V. +A single group of 3 LEDs dissipates 0.36W. At 60LEDs/m that's 7.2W/m. + +We loose 50% brightness due to the 2:1 AC multiplexing and another ~15% due to the generous blanking periods. To make up +for that we need to scale the current by a factor of 2.35. This can be done by increasing VCC from 12.0V to about 14.5V. +Assuming the multiplexing doesn't stop that's not a problem as the power dissipation of the LEDs and dropper resistors +will remain the same as before. We need a safety cutoff in the circle firmware for that though so the LED tape doesn't +burn up if something crashes (FIXME). |