BA6840BFS

Motor driver ICs 3-phase motor driver BA6840BFS / BA6840BFP-Y / BA6840BFP / BA6842BFS The BA6840BFS, BA6840BFP-Y, BA6840BFP, and BA6842BFS are one-chip ICs designed for driving CD-ROM motors. They are high performance-ICs with a 3-phase, full-wave, pseudo-linear drive system. FApplications CD-ROM / RW, DVD-ROM / PLAYER FFeatures 1) 3-phase, full-wave, pseudo-linear drive system. 2) Start / stop pin; power saving during stop mode. 3) Internal current limit circuit. FBlock diagram 4) Internal thermal shutdown circuit. 5) Internal hall bias circuit. 523 Motor driver ICs BA6840BFS / BA6840BFP-Y / BA6840BFP / BA6842BFS FAbsolute maximum ratings (Ta = 25_C) FRecommended operating conditions 524 Motor driver ICs BA6840BFS / BA6840BFP-Y / BA6840BFP / BA6842BFS FElectrical characteristics (unless otherwise noted, Ta = 25_C, VCC = 5V, VM = 12V) 525 Motor driver ICs FElectrical characteristic curves BA6840BFS / BA6840BFP-Y / BA6840BFP / BA6842BFS 526 Motor driver ICs BA6840BFS / BA6840BFP-Y / BA6840BFP / BA6842BFS FCircuit operation (1) Hall input X output The 3-phase Hall signal is amplified in the hall amplifiers and sent to the matrix section, where the signal is further amplified and combined. After the signal is converted to a current in the amplitude control circuit, the current is supplied to the output driver, which then provides a motor drive current. The phases of the Hall input signal, output voltage, and output current are shown in Fig. 5. (2) Torque contr...