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Pin No. Symbol Pin Voltage
LB11985H
Description
Unit (resistance : Ω, current : A )
Equivalent circuit
VCC
Frequency characteristics correction.
Oscillation in the current control system closed loop
22
FC
can be prevented by inserting a capacitor between
this pin and ground.
22
Control reference voltage.
23
CTLREF
1 V to 4 V Although this voltage is set to VCC × (15/35)
(VCC = 5 V) internally, it can be modified by applying a voltage
from a low-impedance circuit.
Speed control.
25
CTL
0 V to VCC
Control consists of a constant current drive scheme
implemented by applying current feedback from
RF.
6S
A13022
VCC
300 Ω
300 Ω
23
18 kΩ
25
50 µA 50 µA
VCC
A13023
Current limiter function control.
24
LIM
0 V to VCC The voltage applied to this pin modifies the output
current linearly.
1 kΩ
24
26
Forward/reverse control.
26
FR
0 V to VCC The voltage applied to this pin selects forward or
reverse operation.
45 kΩ
A13024
VCC
27
ADJ
External torque ripple correction ratio adjustment.
To adjust the correction ratio, apply the stipulated
voltage to the ADJ pin from a low-impedance
external circuit.
If the applied voltage is increased, the correction
ratio rises, and if the applied voltage is lowered, the
correction ratio falls.
6 kΩ 500 Ω 6 kΩ
Power supply for all circuits other than the IC
28
VCC
4.5 V to 5.5 V
internal output block.
This voltage must be stabilized so that ripple and
noise do not enter the IC.
A13025
VCC
27
A13026
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