LB11870 Datasheet, PDF (8/14 Pages) Sanyo Semicon Device – Three-Phase Brushless Motor Driver for Polygonal Mirror Motors

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Pin No. Pin
Function
LB11870
VREG
Sets the PWM oscillator frequency.
17
PWM ^{Insert a capacitor between this pin and ground.}
The PWM oscillator frequency is set to about 34 kHz
when a 680 pF capacitor is used.
Equivalent circuit
200Ω
17
2kΩ
VREG
Frequency characteristics correction for the current
control circuit.
19
FC
Insert a capacitor (about 0.01 to 0.1 µF) between this pin
and ground.
The output duty is determined by comparing the voltage
on this pin to the PWM oscillator waveform.
300Ω
19
Phase comparator output
21
PD
The phase error is converted to a pulse duty and output
from this pin.
VREG
300Ω
21
VREG
22
EI
Error amplifier input
23
EO Error amplifier output
VREG
300Ω
22
23
40kΩ
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