ST1115C Datasheet, PDF (2/13 Pages) Silicon Touch Technology Inc. – PWM Speed Control Double Coil Brushless DC Motor Driver

點晶科技股份有限公司
SILICON TOUCH TECHNOLOGY INC.
ST1115C/ST1115D
ST1115C/ST1115D
PWM Speed Control
Double Coil Brushless DC Motor Driver
General Specifications
The ST1115 serial IC is a driver with pulse-width modulated (PWM) speed control for
two-phase unipolar DC brushless fan applications. The device is used as an interface between a
HALL effect latch and a double coil load. Besides its high-efficiency driving capability, the
ST1115 has various functions such as rotation detection (for ST1115C only), tachometer signal
output (for ST1115D only), linear fan speed control, exterior PWM control, locked-rotor
protection and self-restart.
The speed command can be either a PWM signal or simply a voltage reference according to
the applications. For the temperature-proportional fan speed control, the voltage command can
be generated by an external temperature sensor, typically a thermistor-resistor divider. If the
motor rotation is stalled by external force or obstacles, overdrive current (or lock current) may
incur coil overheat/burning. To prevent coil overheat/burning, this device incorporates
locked-rotor protection circuitry to shut down the drivers. After the motor locking is released,
the drivers can be automatically powered up by the internal self-restart circuitry.
Features and Benefits
z High-efficiency PWM fan speed control
z Linear temperature-speed control with minimum external circuitry
z High output sinking current capability
z Lock protection and automatic self-restart
z Tachometer output
z Directly connectable to a HALL Latch IC
z Thin, highly reliable package ( SOP8, MSOP8 )
SP-ST1115CD-A.005
Version：A.005
Page：1