Features: • 12-V Motor Supply
• Blocking Schottky Diode Replaced by External Synchronous Rectifier
• Spindle Motor Driver Features:
External LITTLE FOOT® Drivers for High Current/Power Application
Constant Off-Time PWM Current Drive Minimizing Power Dissipation
Sensorless Motor Commutation Immune to PWM Noise
Externally Controlled Start-Up/Run Function
Low-Jitter Commutation Output for External Speed Control
Level Shifting Buffer Amplifier for PWM DAC
Adjustable Output Slew Rate Control
Unique Commutation Driver Minimizing Audible Noise
Programmable Phase Advance for High Speed Motor
Speed Triggered Motor Brake for Enhanced Reliability
• Voice Coil Motor Driver Features:
External LITTLE FOOT Drivers for High Current/Power Application
Low Crossover Distortion in Linear Mode (Class AB)
Selectable Constant Frequency PWM or Linear Operation
Programmable Retract Voltage Clamp
Level Shifting Buffer Amplifier for PWM DAC
Direct VCM Retract Control Input
Current Sense Output for Enhanced Servo Control
Fixed PWM Output Slew Rate Limit
• System Manager Features:
Power-On Reset Generator
Adjustable System Voltage Monitor
2.3/5.0-V±5%, 150 ppm/°C Reference Output for External PWM DAC
Programmable Timer for Head Retract and Spindle Brake Delay
Built-In Test Ability
• 3-Wire Synchronous Serial Data Interface
• Internal Registers and Address Decoding with Full Readback CapabilitySpecificationsVoltage Referenced to GND Pin
VDD Supply Range. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-0.3 to 7 V
VCLAMP Supply Range . . . . . . . . . . . . . . . . . . . . . . . . . > (VCC - 0.3 V
and > (VDD - 0.3 V) to 14 V
VCC, VMOT Supply Range . . . . . . . . . . . . . . . . . . . . . . . . .-0.3 to 14 V
AGND, DGND, PWRGND to GND . . . . . . . . . . . . . . . . . . . -0.3 to 0.3 V
SENA, SENB, SENC, CT, VCM+, VCM-Pin . . . . . . . . -1.0 to VCC + 1.0 V
POR, FCOM, STEPCLK, ENCOM, SYSCLK, PWMIN,
PWMOUT, RESETVCM, IPCLK, IPDATA
and IPENABLE pins . . . . . . . . . . . . . . . . . . . . .. . . -0.3 to VDD + 0.3 V
All Other Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3 to VCC + 0.3 V
Maximum Current (All Input Pins) . . . . . . . . . . . . . . . . . . . . . . ±20 mA
Storage Temperature (Tstg) . . . . . . . . . . . . . . . . . . . . . -65 to 150°C
Operating Temperature (TA) . . . . . . . . . . . . . . . . . . . . . . . .0 to 70°C
Junction Temperature (TJ). . . . . . . . . . . . . . . . . . . . . . . . . . . . .150°C
Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 W
Thermal Impedance (QJA) . . . . . . . . . . . . . . . . . . . . . . . . . .6.25°C/W
* Exposure to Absolute Maximum rating conditions for extended periods may affect device reliability. Stresses above Absolute Maximum rating may cause permanent damage. Functional operation at conditions other than the operating conditions specified is not implied. Only one Absolute Maximum rating should be applied at any one time. Device mounted on one-inch square FR4 Board.
DescriptionThe Si9993CS consists of a 3-phase brushless dc motor (spindle) PWM controller and a linear/PWM transconductance stage suitable for driving a voice coil motor (head actuator). To meet the power handling capability required for a high capacity hard disk drive, both drivers utilize external LITTLE FOOT half-bridges (Siliconix Si9942 recommended). A separate LITTLE FOOT PMOS switch (Si9430) is used as a synchronous rectifier in place of the usual Schottky blocking diode.
Si9993CS is manufactured in a junction-isolated BiC/DMOS process (JIBCD15) and is available in a 64-pin SQFP package, specified to operate over the commercial (0°C to 70°C) temperature range.
Si9993CS Data Sheet
