L6207 datasheet(35/53 Pages) STMICROELECTRONICS

35 / 53 page

35/53

AN1762 APPLICATION NOTE

Running the evaluation board in stand-alone mode, instead, R17 and R21 set the reference voltage separately

for the two bridges, while R16, C9 and R20, C12 are low-pass filters to provide an external reference voltage

by a PWM output of a µC (see also the Microstepping section). Using external VREF inputs R15, R17, R19, R21

can be disconnected through JP4 and JP5, unless the PractiSPIN ST7 evaluation board is used. This board, in

fact, is provided with an offset cancellation circuitry trimmable through a potentiometer (see PractiSPIN docu-

mentation).

Closing JP2 and JP3 is recommended for safe Over Current Protection.

The 5V voltage for logic inputs and for references (VrefA and VrefB) is obtained from R2, D3. Depending on the

supply voltage, the value of resistor R2 should be changed in order to ensure a correct biasing of D3.

The jumper JP1 allows choosing the 5V voltage from the internal zener diode network or pin 11 of CN5 (for ex-

ample an external µC board can provide 5V to the evaluation board). Also CN2 connector can be used to pro-

vide an external 5V voltage to the board (in that case R2, D3 should be disconnected). CN2, or pin 1 of CN5,

can also be used to provide a 5V voltage to external circuits (as, for example, the PractiSPIN ST7 board). In this

case the current that can be drawn form the board depends on the supply voltage and on R2 value.

Figure 39 to Figure 41 show the component placement and the two layers layout of the L6205N Evaluation

Board. A large GND area has been used, to guarantee minimal noise and good power dissipation for the device.

Figure 37. EVAL6205N.

5.2.1 Important Notes

JP1 : close in INT position for use with PractiSPIN ST7 board

C6, C7 : recommended change to 5.6 nF for safe Overcurrent protection

R3, R4 : recommended change to 100 k for safe Overcurrent protection

R5, R6 : recommended change to 100 k if EN pins are driven from the CN5 connector (for example with Prac-

tiSPIN ST7 board) for safe Overcurrent protection

R17, R21 : set the maximum current obtainable through PractiSPIN (see PractiSPIN documentation)

R2 : recommended change to adequate value (depending on supply voltage) to obtain 5V across D3

JP2, JP3 : close for safe Overcurrent protection

JP4, JP5 : close for use with PractiSPIN ST7 board

JP1

R4 R6

R17

R21

JP2

JP3

JP4

JP5

L6207 数据表(PDF) 35 Page - STMicroelectronics

L6207 数据表(HTML) 35 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53

数据表下载