LS7261-LS7262 three-phase half-wave circuit

For a three-phase brushless DC motor with a center tap, when using this circuit, only
three power switches on the lower arm are used. The center tap should be connected to the power supply V to form
a three-phase half-wave connection. When a braking function is required , should be connected as shown in Figure 3-4. The center
tap of the motor is connected to V through a power tube. This power transistor is controlled by the BRAKE signal.
When BRAKE is l, the power transistor is cut off, and the power tube of the lower arm makes the motor
Three-phase winding short circuit braking.
    Pin 10 (ENABLE): Enable terminal. When this pin is high, the circuit operates normally
. When applied low, all outputs are disabled. There is a pull-up resistor in this pin. In
addition, the positive edge of the input signal of this pin can reset the overcurrent RS
trigger of LS7260/LS7262.
    Pin 12 (OVERCURRENT SENSE): Overcurrent detection terminal. The user
can use this pin to protect the motor windings, drive circuitry, and power supply during overload conditions.
Add a small resistor in series to the ground end of the drive bridge as current detection. The detection signal is connected to
an iOOkfl potentiometer, and the other end of the potentiometer is connected to the positive pole of the power supply. Adjust this potentiometer
so that the system is disabled when the motor current is just above the upper limit. Theoretically, the operating point of the
overcurrent detection circuit is V ss,/2, and its manufacturing error is ±0.25v. For
the manufactured chip, due to time or temperature changes, the deviation of this action voltage is
within iOmV. LS7260 and LS7262 are blocked when overcurrent occurs. When the positive edge of the sawtooth wave oscillator
or the positive edge of the ENABLE input is reset, the flip-flop is reset and released.
ENABLE can also be used to input the chopper signal. At this time, the oscillator pin should be connected to Vss.