tda5240t NXP Semiconductors, tda5240t Datasheet - Page 12

• Manufacturer Part Number: tda5240t
• Description: Brushless Dc Motor Drive Circuit
• Manufacturer: NXP Semiconductors

~ The timing capacitor;
Analog control of the motor output voltages
fixed. Compensation
ADJUSTMENTS
The system has been designed
the approximate
THE START CAPACITORS (CAP-ST)
This capacitor
The start oscillator
from the start oscillator will cause the outputs to change to the next state (torque in the motor) .If the movement
Both grounds GND1 and GND2 must be connected
.The
.The
(This deals with the application
0.05 to 2.2 V and back to 0.05 V. The time taken to complete one cycle is given by:
generates enough EMF the TDA5240T
The amplitude
arriving during the wrong phase of the oscillation.
move one step only and will oscillate in its new position.
for commutation,
Philips
November
Brushless
two capacitors
start capacitor;
Semiconductors
96
determines
of the oscillation
values of the following
is reset by a commutation
depending
of the motor pole is done by an external capacitor
in the adaptive commutation
DC motor drive circuit
this determines
this provides the system with its timing signals
the frequency
on the type and loading of the motor
note AN94070)
must decrease
in such a way that the tolerances
the frequency
will run the motor. If the amount of EMF generated
components
of the start oscillator.
tstart = (2.15 X C)s
is achieved
pulse and so is only active when the system is in the start-up mode. A pulse
sufficiently
'osc
The oscillation
delay circuit. These are important
together.
of the start oscillator
must still be determined:
= ¥ x ( Kt x I x J )2
by an internal operational
before the arrival of the next start pulse, to prevent the pulse
12/19
It is charged and discharged,
of the motor is given by:
of the application
(with C in ~F)
(CAP CPC).
1
amplifier which tranfer gain is internally
components
in determining
is insufficient,
with a current of 2 ~A, from
are not critical. However,
the optimum
Product specification
TDA5240T
then the motor will
of the motor
moment