P. Short
07-21-2007, 04:58 PM
I've made some changes to the BOM for these two boards in the wiki (which is now the official location for the BOMS). The changes involve the power section of these boards.
For the Renard8 board, I am now recommending the use of a Schottky diode and an LDO regulator (although the old parts can still be used if the input voltage to the board is high enough (8V peak if unfiltered DC, 7.5V if filtered). The reason for this change is to allow the use of the transformer board with a 12.6VAC CT or 6.3V transformer.
For the Renard64 board the situation depends on whether the PWM firmware is used, or not. If the PWM firmware is used, the regulator parts should be omitted and the board powered from an external 5V regulated power supply. This is because there isn't any workable combination of input voltage, filter cap, and regulator (there isn't enough room on the board for bigger filter caps or for a good heatsink).
If the non-PWM firmware is used, D1 should be a Schottky diode and the regulator should be an LDO part (L4940 or similar). The reason for using these parts is so that the transformer board can be used with the same type of transformers described above.
Similar considerations apply to the xmus Renard16 with integrated SSR board, although the existing BOM will work if the input voltage to the board is high enough.
--
Phil
Edit - I also changed the values of the (optional) current limit resistors for the per-channel status LEDs. This was done to decrease the current requirements for the board.
--
Phil
For the Renard8 board, I am now recommending the use of a Schottky diode and an LDO regulator (although the old parts can still be used if the input voltage to the board is high enough (8V peak if unfiltered DC, 7.5V if filtered). The reason for this change is to allow the use of the transformer board with a 12.6VAC CT or 6.3V transformer.
For the Renard64 board the situation depends on whether the PWM firmware is used, or not. If the PWM firmware is used, the regulator parts should be omitted and the board powered from an external 5V regulated power supply. This is because there isn't any workable combination of input voltage, filter cap, and regulator (there isn't enough room on the board for bigger filter caps or for a good heatsink).
If the non-PWM firmware is used, D1 should be a Schottky diode and the regulator should be an LDO part (L4940 or similar). The reason for using these parts is so that the transformer board can be used with the same type of transformers described above.
Similar considerations apply to the xmus Renard16 with integrated SSR board, although the existing BOM will work if the input voltage to the board is high enough.
--
Phil
Edit - I also changed the values of the (optional) current limit resistors for the per-channel status LEDs. This was done to decrease the current requirements for the board.
--
Phil