Optical disc ICs 6-channel BTL driver for CD players BA5936S The BA5936S is a 6-channel BTL driver developed for use as the sled motor, spindle motor, actuator, and loading motor driver for CD players. It contains a current limiting function and 5V regulator for compatibility in a wide range of applications. Applications CD players Features 1) 6-channel BTL driver for CD players. Contains 4 channels for the focus coil, tracking coil, sled motor, and spindle motor drives; and 2 channels for the loading motor driver. 2) Internal 5V regulator with a earth protection circuit (requires an external PNP transistor). Absolute maximum ratings (Ta = 25C) Recommended operating conditions (Ta = 25C) 708 3) Internal mute circuit (enables the muting of the driver outputs from all but the loading driver, and muting of the regulator output). 4) Internal thermal shutdown circuit. Optical disc ICs BA5936S Block diagram 709 Optical disc ICs Pin descriptions Input / output circuits 710 BA5936S Optical disc ICs BA5936S 711 Optical disc ICs BA5936S Electrical characteristics (unless otherwise noted, Ta = 25C, VCC = 8V, RIN = 10kΩ, RL = 8Ω, VBIAS = 2.5V) 712 Optical disc ICs BA5936S Measurement circuit 713 Optical disc ICs Application example 714 BA5936S Optical disc ICs BA5936S Operation notes (1) Output mode switch for loading motor driver (VCC = 8V) (2) Loading motor driver voltage setting (ex: forward mode) (3) The BA5936S contains a thermal shutdown circuit. When the chip temperature reaches 175C (Typ.), the output current is muted. If the chip temperature then drops below 150C (Typ.), then the mute is released. (4) By having the mute pin (pin 27) voltage open or lowered to 0.5V or below, the output currents (channels 1, 2, 4, and 5, and regulator) can be muted. For normal conditions, have the voltage at pin 27 pull-up to 2V. (5) If the voltage of the bias pin (pin 24) drops below 1.4V (Typ.), the drivers (channels 1, 2, 4, and 5) are muted. For normal conditions, have the voltage at 1.6V or greater. 715 Optical disc ICs BA5936S (6) If the voltage of the thermal shutdown or bias pin drops, the mute is activated; however, in both these situations, only the drivers and regulator are muted. Also, the output pin voltage becomes the internal bias voltage (approx. (VCCVF) / 2 [for channels 1, 2, 4, and 5], VCC / 2 [for channels 3 and 6]). = Supplement = Various mute function and corresponding driver and regulator operating conditions (7) Connect a bypass capacitor (approx. 0.1µF) between the bases of the power supply pins of this IC. (8) The regulator characteristics are explained below. The limiting current and ground current can be set by changing the external current limiting resistor and external PNP transistor hfe. ∗ Do not use loads that will change the regulator load characteristics and regulator current limiting characteristics. Doing so may cause start-up malfunctions. 716 (9) The application example will assure excellent results, but nevertheless, be sure to carefully check all characteristics during use. During use with constants in the external circuitry modified, be sure to leave a sufficient margin in order to take into consideration fluctuations in the static and transient characteristics of the external components and this IC. Also, be aware that ROHM has not sufficiently performed all confirmations regarding patent rights. Optical disc ICs BA5936S Electrical characteristic curves External dimensions (Units: mm) 717