Data Sheet

TB67S249FTG

2017-08-18

5. RESET function

The RESET pin initializes the internal electrical angle.

Note: Built-in digital filter of 0.625 μs (±20 %) is adopted to RESET pin.

RESET

Function

High

Initializes the internal electrical angle

Low

Normal operation

When the RESET pin is set to High, the current setting for each H-bridge (Ach and Bch) will be set to the value below. Also,

the MO pin outputs Low level when the electrical angle corresponds to the initial value.

Step resolution Ach current Bch current Electrical angle

1/32 step setting 71 % 71 % 45°

1/16 step setting 71 % 71 % 45°

1/8 step setting 71 % 71 % 45°

1/2 (b) step setting 71 % 71 % 45°

1/4 step setting 71 % 71 % 45°

1/2 (a) step setting 100 % 100 % 45°

1/1 step setting 100 % 100 % 45°

6. MO (Monitor output: electrical angle monitor) function

MO pin outputs an internal initial electrical angle as a signal. The MO is an open drain type pin; therefore to use the function

properly, please pull up the MO output to VCC. (The pull-up resistor value should be set between 10 kΩ and 100 kΩ.) The

pin level is high impedance (Hi-Z) during the normal operation (internal MOSFET is turned off and pin voltage is VCC). And

when the internal electrical angle is equal to the initial angle, the pin level will be Low (internal MOSFET is turned ON) as

shown below.

MO Function

VCC (Hi-Z)

Electrical angle is not at the initial position

Low

Electrical angle is at the initial position

Note: Hi-Z: High impedance state

Note: The equivalent circuit diagrams may be simplified or some parts of them may be omitted for explanatory purposes.

(10 kΩ to 100 kΩ)

VCC

If the electrical angle is equal to the initial

angle, the internal MOSFET is turned on and

the pin voltage level is Low.

If the electrical angle is not equal to the initial

angle, the internal MOSFET is turned off and

the pin voltage level is High (VCC).