BA6795

Optical disc ICs 5-channel BTL driver for CD players BA6795FP The BA6795FP is a 5-channel BTL power driver for CD players and has an internal 5V regulator (attached PNP transistor required). The loading and spindle motor output pins are dual-use output pins and are switched between drivers using a control input. In addition, the internal level shifting circuit reduces the number of external components. FApplications CD players, CD-ROM drives and other optical disc devices FFeatures 1) 5-channel BTL driver in a HSOP 28-pin package, ideal for application miniaturization. 2) Internal level shifting circuit reduces the number of external components. FAbsolute maximum ratings (Ta = 25_C) 3) Gain is adjustable with an attached resistor. 4) Internal thermal shutdown circuit. 5) Internal 5V regulator. (attached PNP transistor required) FRecommended operating conditions (Ta = 25_C) 472 Optical disc ICs FBlock diagram BA6795FP 473 Optical disc ICs FPin descriptions BA6795FP 474 Optical disc ICs FElectrical characteristics (unless otherwise noted, Ta = 25_C, VCC = 8V, f = 1kHz, RL = 8Ω) BA6795FP 475 Optical disc ICs FMeasruement circuit BA6795FP 476 Optical disc ICs FMeasruement circuit switch table BA6795FP 477 Optical disc ICs FCircuit operation (1) Switching between spindle and loading motor driver output modes (VCC = 8V) BA6795FP 478 Optical disc ICs FCircuit operation (2) Loading motor driver voltage setting (forward mode) BA6795FP 479 Optical disc ICs FApplication example BA6795FP 480 Optical disc ICs FOperation notes (1) The BA6795FP has an internal thermal shutdown circuit. Output current is muted when the chip temperature exceeds 175_C (typically). (2) If the mute pin (pin 7) voltage is opened or lowered below 0.5V, the output current will be muted. Pin 7 should be pulled up above 2.0V during normal use. (3) The bias pin (pin 23) is muted when lowered below 1.4V (typically). Make sure it stays above 1.6V during normal use. (4) Muting occurs during thermal shutdown, mute-on operations or a drop in the bias pin voltage or supply voltage. In each case, only the drivers are muted. During muting, the output pins remain at the internal bias voltage, roughly (VCC–VF) / 2. BA6795FP (5) The driver circuit shuts down when the supply voltage drops below 4.3V (typically), and starts up again when the voltage rises above 4.5V (typically). (6) Fluctuation due to temperature occurs in the gain when using an attached resistor as the input resistor for a driver other than the spindle driver (typically 2200ppm per degree) or for the spindle driver (typically 4600ppm per degree. (Only when using the gain adjustment pin.) (7) Be sure to connect the IC to a 0.1µF bypass capacitor to the power supply, at the base of the IC. (8) The radiating fin is connected to the package’s internal GND, but should also be connected to an external ground. (9) The capacitor between regulator output (pin 6) and GND also serves to prevent oscillation of the IC, so select one with good temperature characteristics. FElectrical characteristic curves 481 Optical disc ICs FExternal dimensions (Units: mm) BA6795FP 482