Abstract: Provided is a controller circuit of a buck DC/DC converter. The controller circuit includes a feedback pin to be connected to an output line of the buck DC/DC converter, a voltage divider circuit including a first resistor and a second resistor connected in series between the feedback pin and a ground, a feedback circuit that generates a pulse modulation signal to bring a feedback voltage as an output of the voltage divider circuit close to a reference voltage, and a current source that is connected to the feedback pin and supplies a constant current.

Abstract: A door assembly allows one to easily and freely change a hinged side and an opening direction of a door when or after a resident moves into a house. Detachable inner frames having doorstop portions, flat portions, and locking nails are mounted to locking grooves in left and right vertical outer frames around spacers and a door main body is mounted to a heelpost side flat portion through hinges. By dividing a doorframe into the vertical outer frames and the inner frames, in order to change a hinged side of the door, the inner frames are pulled out from the vertical outer frames and inserted into the locking grooves in the vertical outer frames after changing orientation of the inner frames according to the hinged side or exchanging the inner frames for the inner frames suitable for the hinged side and the opening direction to thereby easily change the hinged side of the door main body.

Abstract: It is possible to easily and freely change a hinged side and an opening direction of a door when or after a resident moves into a house. Detachable inner frames having doorstop portions, flat portions, and locking nails are mounted to locking grooves in left and right vertical outer frames through spacers and a door main body is mounted to the heelpost side flat portion through hinges. By dividing a doorframe into vertical outer frames and inner frames, in order to change a hinged side of the door, inner frames are pulled out from the vertical outer frames and inserted into the locking grooves in the vertical outer frames after changing orientation of the inner frames according to the hinged side or exchanging the inner frames for inner frames suitable for the hinged side and the opening direction to thereby easily change the hinged side of the door main body.