
Philips Electronics
GENERAL DESCRIPTION
The TDA5345HT is a combination of a voice coil motor and a spindle motor driver, designed for 5 V high performance portable small form factor hard disk drives. Communications with the micro-controller take place through a 16-bit 3-wire uni-directional serial port. Power dissipation is a major concern in portable drives, therefore each main function can be individually put in sleep mode when it is not used, to save as much power as possible. The serial port and the power monitor are the only functions which remain always active.
FEATURES
• Single chip voice coil and spindle motor drivers:
• Complementary outputs (Nmos & Pmos): No step-up converter needed
• On-chip isolation switch to allow synchronous rectification at power-down
• Suited for ramp load operation
• Register based architecture: on-chip serial interface
• Temperature shut down protection
• Linear 3.3 V regulator using one external NPN transistor
• Power monitor circuitrymonitoring the 5 V supply
• 1 axis shock sensor amplifier
• Switched capacitor regulator (-3 V) using 2 external capacitors and 2 external shottky diodes
• All main internal functions can be independently put in Sleep mode
• Small low profile package: TQFP64 (1.2 mm high).