Rohm BA6849FP free download

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Motor driver ICs 3-phase motor driver for CD-ROMs BA6849FP / BA6849FP-Y / BA6849FM / BA6849FS The BA6849 series are ICs developed for CD-ROM spindle motor drives. These ICs possess a short brake and reverserotation brake for two types of brake functions, and also contain FG output and rotation direction detection (FR) circuits, making them high-functionality and high-performance ICs. FApplications CD-ROM, CD-R, CD-RW, DVD-ROM, and DVD-RAM FFeatures 1) Three-phase, full-wave, pseudo-linear drive system. 2) Built-in power save and thermal shutdown functions. 3) Built-in current limiter and Hall bias circuits. 4) Built-in FG output. FAbsolute maximum ratings (Ta = 25_C) 5) Built-in rotation direction detector. 6) Built-in reverse rotation prevention circuit. 7) Built-in short brake pin. 863 Motor driver ICs BA6849FP / BA6849FP-Y / BA6849FM / BA6849FS FRecommended operating conditions (Ta = 25_C) FBlock diagram 864 Motor driver ICs FPin descriptions BA6849FP / BA6849FM BA6849FP / BA6849FP-Y / BA6849FM / BA6849FS BA6849FP-Y 865 Motor driver ICs MA6849FS BA6849FP / BA6849FP-Y / BA6849FM / BA6849FS 866 Motor driver ICs FInput / output circuits (1) Power save BA6849FP / BA6849FP-Y / BA6849FM / BA6849FS (2) Torque command input (3) Torque output (A1, A2, and A3) (4) Hall input (H1), H1­, H2), H2­, H3), H3­) 867 Motor driver ICs (5) Hall bias BA6849FP / BA6849FP-Y / BA6849FM / BA6849FS (7) FR Output (6) FG output (8) Short brake Note: Resistance values are typical values. 868 Motor driver ICs BA6849FP / BA6849FP-Y / BA6849FM / BA6849FS FElectrical characteristics (unless otherwise noted, Ta = 25_C, VCC = 5V, VM1 = 12V, VM2 = 12V) 869 Motor driver ICs BA6849FP / BA6849FP-Y / BA6849FM / BA6849FS FCircuit operation (1) Hall input to coil output The phase relationship between the Hall input signals and the output current and voltage is shown in Fig.9. The motor position data input via the Hall pins is amplified by the Hall amplifier, and formed into waveforms by the matrix block.These signals are input to the output driver that supplies the drive current to the motor coils. 870 Motor driver ICs BA6849FP / BA6849FP-Y / BA6849FM / BA6849FS (2) Torque command The RNF pin voltage with respect to the torque command (EC) is as follows: The I / O gain (GEC) from the EC pin to the RNF pin (output current) is determined by the RNF detector resistor. GEC = 0.255 / RNF [A / V] The torque limit current ITL is given by: ITL = 0.35 / RNF [A] (3) Reverse rotation detection function The reverse detection circuit construction is shown in Fig.11. (1) Forward (EC < ECR) The phase relationship between the Hall input signals H2) and H3) becomes as shown in Fig.9, and the reverse rotation detection circuit does not operate. (2) Reverse (EC > ECR) The phase relationship between the signals H2) and H3) is opposite that for forward operation, and the reverse rotation detection circuit operates. The output goes OFF, and becomes open circuit.