LV8811GEVB Evaluation Board User Guide
4. Minimum Duty Cycle Setting
To set the minimum duty cycle, a user needs to solder chip resistors.
The minimum duty cycle for disable (stop)
D
MIND
is determined by the voltage level
V
MDS
at MDS pin.
𝐷𝐷
𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀
=
48 − 4
2.906 − 0.141
(𝑓𝑓
𝑀𝑀𝑀𝑀𝑀𝑀
− 0.141) + 4 = 15.9𝑓𝑓
𝑀𝑀𝑀𝑀𝑀𝑀
+ 1.758
when 𝑓𝑓
𝑀𝑀𝑀𝑀𝑀𝑀
= 0
𝐷𝐷
𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀
= 8%
There is 6% of histeresisy between enable (start) and disable (stop) tarnsistions.
𝐷𝐷
𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀
= 𝐷𝐷
𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀
+ 6
The voltage level
V
MDS
in this board is determined by resistors.
𝑓𝑓
𝑀𝑀𝑀𝑀𝑀𝑀
= 𝑓𝑓
𝑅𝑅𝑀𝑀𝐹𝐹
𝑅𝑅
17
+ 𝑅𝑅
18
𝑅𝑅
15
+ 𝑅𝑅
16
+ 𝑅𝑅
17
+ 𝑅𝑅
18
𝑓𝑓
𝑅𝑅𝑀𝑀𝐹𝐹
= 3[V] in the board
5. Lead angle tuning
To tune the lead angle, a user needs to solder chip resistors.
The minimum lead angle at the lowest rotational speed
P
0
is determined by the voltage
level
V
PH1
at PH1 pin.
𝑃𝑃
0
=
60 − (−30)
2.906 − 0.141
(𝑓𝑓
𝑃𝑃𝑃𝑃1
− 0.141) − 30 = 32.55𝑓𝑓
𝑃𝑃𝑃𝑃1
− 34.59
when 𝑓𝑓
𝑃𝑃𝑃𝑃1
= 0
𝑃𝑃
𝑂𝑂
= 15°
The lead angle P is dynamically adjusted with respect to FG frequency fFG.
𝑃𝑃 = 𝐴𝐴𝑓𝑓𝑓𝑓
𝐹𝐹𝐹𝐹
+ 𝑃𝑃
0
𝐴𝐴 =
0.3
2.906 − 0.141
(𝑓𝑓
𝑃𝑃𝑃𝑃2
− 0.141) = 0.1085𝑓𝑓
𝑃𝑃𝑃𝑃2
when 𝑓𝑓
𝑃𝑃𝑃𝑃2
= 0
𝐴𝐴 = 0.15°/𝐻𝐻𝐻𝐻
The voltage levels
V
PH1
and
V
PH2
in this board are determined by resistors.
𝑓𝑓
𝑃𝑃𝑃𝑃1
= 𝑓𝑓
𝑅𝑅𝑀𝑀𝐹𝐹
𝑅𝑅
5
+ 𝑅𝑅
6
𝑅𝑅
3
+ 𝑅𝑅
4
+ 𝑅𝑅
5
+ 𝑅𝑅
6
𝑓𝑓
𝑃𝑃𝑃𝑃2
= 𝑓𝑓
𝑅𝑅𝑀𝑀𝐹𝐹
𝑅𝑅
9
+ 𝑅𝑅
10
𝑅𝑅
7
+ 𝑅𝑅
8
+ 𝑅𝑅
9
+ 𝑅𝑅
10
𝑓𝑓
𝑅𝑅𝑀𝑀𝐹𝐹
= 3[V] in the board
*The calculating formula of the adjustment of MDS and PH1,PH2 becomes the reference level. Please
confirm real movement with a motor to use.
Page 7
