Speed Control Part
Use a rail-to-rail Op-Amp.
8.4.1. Parameter adjustment
R1 and R2:
if VSP=VMAX represents max speed, and LA=VLAMAX at max speed.
Adjust R1 and R2 so that
R3: The factor of proportional control Kp is related to R3. Increase R3 to increase Kp.
C1: The factor of integral control Ki is related to C1. Increase C1 to increase Ki.
R5 and R6 :
Adjust R5 and R6 to ensure Dif-in will not exceed 3V.
If Dif-in=VMIN makes motor run at min speed, it is recommended to set R5 and R6 so that
<5× 6/( 5+ 6)<3.
Total resistant of R5 and R6 should be around 50k to 100k.
Toshiba Electronic Devices & Storage Corporation
Figure 8-4 Speed Control Part
× 2/( 1+ 2)
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