Brushless dc motor having high power density for power tool

A motor comprising:

• a rotor supporting a plurality of magnets and driving an output;
• a stator comprising a stator core including a plurality of stator teeth defining a plurality of slots therebetween, a plurality of stator windings wound on the plurality of stator teeth, and an end insulator located between the stator core and the plurality of stator windings, wherein the stator has an outer diameter in the range of approximately 40 mm to approximately 70 mm;
• and
• a circuit board disposed adjacent the end insulator and electrically connected to the plurality of stator windings to supply electric power to the stator;
• wherein a ratio of a motor size (Km) constant of the motor to an electrical envelope of the motor is in the range of approximately 850 (N.m/√W)/m{circumflex over ( )}3 to approximately 1042 (N.m/√W)/m{circumflex over ( )}3, wherein the electrical envelope of the motor is radially bound by an outer cylindrical boundary of the stator assembly and axially bound by a front radial plane located at a frontmost point of the stator windings and a rear radial plane located at a rearmost point of the circuit board.