EVAL6207N Datasheet, PDF (15/34 Pages) STMicroelectronics – PractiSPIN evaluation system configuration and set up guide

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EVAL6206N board configuration
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EVAL6206N board configuration
Note:
The schematic of the EVAL6206N board is shown in Figure 4. To use the EVAL6206N board
with practiSPIN system, the following configuration settings must be made on the
EVAL6206N:
1. Component updates: depending on the revision of the board, some or all of the
following changes may be required (or desirable):
a) To assure safe overcurrent operation:
– Change C6 and C7 to 5.6 nF
– Change R5 and R6 to 100 kΩ
b) To assure an adequate 5 V supply, R2 may need to be changed. The minimum
value for R2 is (Vs-5)/(0.03+I) Ω . Where: Vs is the supply voltage and I is any
additional load placed on the 5 V supply (in amps).
2. JP1: place JP1 in the INT position to enable the on-board 5 Vdc supply.
3. JP2 and JP3: install JP2 and JP3 to enable the L6206's internal high side overcurrent
protection.
4. JP4 and JP5: install JP4 and JP5 to set internal overcurrent threshold to maximum. If
desired, these jumpers can be left out and the overcurrent levels may be set using
potentiometers R7 and R8.
5. JP6 and JP7: install JP6 and JP7 to configure the Vref circuits.
6. R20 and R26 adjust multi-turn trim pots R20 and R26 fully clockwise.
A slight click can be heard from the pot when it reaches its end of travel.
7. R29: adjust multi-turn trim pot R29 to the middle of its range. This pot sets the chopping
frequency of the L6506 current controller and can be fine tuned while observing the
motor current on an oscilloscope or by simply adjusting to raise the frequency of the
audible switching noise to an inaudible level if required.
8. Motor connections: connect the motor coils at CN3 and CN4. When driving a stepper
motor, one winding is connected to CN3 and the second winding is connected to CN4.
For operation with 2 DC motors one motor is connected to each connector.
9. Power supply: connect, but do not energize, a 12 to 48 Vdc power supply at CN1
(positive to V_in and negative to GND).
10. Using a 34 pin ribbon cable connect the EVAL6205N board to the control interface
board. The two boards should be placed on the bench so that their 34 pin headers are
side by side with the ribbon cable going straight across. Set the following on the ST7
interface board.
11. WJ1: install WJ1 on the ST7 based Control Interface Board. This allows 5 Vdc power to
be obtained from the target board.
12. JP1 and JP2 and R18: install the JP1 and JP2 jumpers to short the center and left pins
together as shown in Figure 2. This is critical as excessive motor current can result
from misplacement of these jumpers! Set potentiometer R18 to about 50% .
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