Designers of small form-factor, high performance hard disk drives (HDD) for portable computer systems can now shrink the space needed for these drives while improving performance with the TLS2205, a new, highly integrated low-power motor driver.
The programmable TLS2205 hard-disk motor driver is the industry's first voice-coil/spindle motor driver capable of spinning multiple 2.5 inch, or smaller, platters. It effectively drives the actuator arm and spindle motor, monitors system voltage and performs braking and automatic head retract functions, thereby preventing data loss.
The voice-coil power amplifier is capable of 0.4-A output current and has a 2-½ total rDS(on), thus ensuring low power dissipation. An internal 8-bit monotonic DAC with four gain ranges provides precise control of the voice coil motor. The TLS2205 simplifies system designs and saves board space.
Unlike comparable devices, the retract control circuitry is fully integrated and needs no additional components to isolate this function from the system power supply.
The low resistance levels of the TLS2205 are made possible by the LinBiCMOSTM technology in which the device is manufactured. During normal operation the device dissipates no more than 1 watt of power, while in stand-by mode the power consumption is a mere 17 mW.
Further design simplification is enabled by the TLS2205's three wire serial communication port. It can interface directly to various processors, including the TMS320C2x digital signal processor, as well as 8-bit or 16-bit general purpose microprocessors.
The TLS2205 is characterized for operation over the temperature range of 0_ to 70_C and is the latest in a long line of HDD integrated circuit developments from Texas Instruments.
The TLS2205 comes in a 56-pin shrink small outline package (SSOP), featuring a lead frame with copper bat-wing tabs to dissipate heat.
Vol 9, Summer, 1994