S8082
3. Output Part Circuit & Speed Control
V1
Q1
Q4
V2
Q9
Q7
Q8
Q5
Q2
Q10
R1
R3
Vctl
Vctl
Vo1
Vo2
M
Q3
Q6
R2
R4
[ Forward Rotation : VIN1( H ), VIN2( L ) ]
V1 = Vctl + 2 Vbe(Q7,Q8)
Vo1 = V1 - 2Vbe(Q1,Q2) = Vctl + 2 Vbe(Q7,Q8) - 2Vbe(Q1,Q2) = Vctl
Vo2 = Vsat(Q6)
Vout = Vo1 – Vo2 = Vctl – Vsat(Q6)
[ * Therefore, Vout level depends on the Vctl pin’s level for Speed Control ]
KSD-I7F014-003
7
SEPT., 2010 REV. 03
1ch Bi-directional Motor Driver