The UCC3626 motor controller device combines many of the functions required to design a high-performance, two- or four-quadrant, threephase, brushless dc motor controller into one package. SN74LS670D Texas Instruments(TI) IC 4X4 REG FILE TRI-ST 16-SOIC  Rotor position inputs are decoded to provide six outputs that control an external power stage. SN74LS670D Texas Instruments(TI) IC 4X4 REG FILE TRI-ST 16-SOIC A precision triangle oscillator and latched comparator provide PWM motor control in eithervoltage- or current-mode configurations. The oscillator is easily synchronized to an external master clock source via the SYNCH input. Additionally, a QUAD select input configures the chip to modulate either the low-side switches only, or both upper and lower switches, allowing the user to minimize switching losses in less demanding two-quadrantapplications. SN74LS670D Texas Instruments(TI) IC 4X4 REG FILE TRI-ST 16-SOIC The device includes a differential current-sense amplifier and absolute-value circuit which provide an accuratereconstruction of motor current, useful for pulse-by-pulse overcurrent protection, SN74LS670D Texas Instruments(TI) IC 4X4 REG FILE TRI-ST 16-SOIC as well as closing a current control loop. A precision tachometer is also provided for implementing closed-loop speed control. The TACH_OUT signal is a variable duty-cycle, frequency output, which can be used directly for digital control or filtered to provide an analogfeedback signal. Other features include COAST, BRAKE, and DIR_IN commands, along with a direction output, DIR_OUT.