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(6) 3-Phase Comparator
This comparator is used for detecting the phase of the 3-phase motor driver. The IN terminal of one pin is commonly used for
+ input terminal. – input terminal is commonly used for each of the three 3-phase driver outputs. When the Int STB signal is
"L", the output is fixed at "L", and operates at "H". The 3-phase comparator does not affect the OE terminal.
Functions Table
Int STB
U, V, WO
L
L
H
Comparator operations
(7) Regulator (VREG)
A voltage follower with a input voltage in which VC is divided by R1 and R2 is provided. The ratio of R1 (28 kΩ) to R2 (252
kΩ) is 1:9, and a 0.9 ×VC voltage is input to the voltage follower. As the CFPF terminal is equipped with a capacitor to form
a LPF, affects by VC ripples, etc. are reduced. At the rising edge of VC, the PMOS mounted in a parallel with R1 remains ON
while Int STB is "L" to speed up the rising time of the CLPF terminal. The voltage follower sets into the standby state when
the OR of D0 and D1 is "L". Its output then becomes High-Z, and it starts operating at "H". While the voltage follower is
operating, the mode is switched according to the VC voltage level and VREG CONT terminal. As described in the bias control
section, as Int STB contains hysteresis against VC, when VC rises, VREG switches from VC to 0.9 ×VC at 2.1V. When it
falls, VREG switches from 0.9 ×VC to VC at 1.4V. When VREG CONT is "L", VREG becomes High-Z.
Functions Table
D0 or D1
VC
L
X
H
Below 1.4V
H
Below 1.4V
H
Above 2.1V
H
Above 2.1V
VC
Fig. 6 3-Phase Comparator
VC
VREG
65
CONT
VREG
64
0.1uF
CL
RGND
66
Fig. 7 Regulator (VREG)
VREG CONT
VREG
X
Z
L
Z
H
VC
L
Z
H
0.9VC
IN
19
Hou
21
Hov
23
How
25
WO
18
VO
17
16
UO
REN
VC
int STB
R1
R2
67
CLPF
0.01uF
— 70 —
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