SA306 Datasheet, PDF (8/14 Pages) Cirrus Logic – 3 Phase Switching Amplifier

SA306
Product Innovation From
2. SA306 OPERATION
The SA306 is designed primarily to drive three phase motors. However, it can be used for any application requir-
ing three high current outputs. The signal set of the SA306 is designed specifically to interface with a DSP or
microcontroller. A typical system block diagram is shown in the figure below. Over-temperature, Short-Circuit and
Current Limit fault signals provide important feedback to the system controller which can safely disable the output
drivers in the presence of a fault condition. High side current monitors for all three phases provide performance
information which can be used to regulate or limit torque.
Figure 4. System Diagram
V_DD
Vs (phase A)
Vs +
Vs (phase B&C)
SC
TEMP
I_LIM/D IS 1
Current ^Ia
monitor ^Ib
Signals Ic
Fault
Logic
GND
D IS 2
At
Ab
PWM B t
Signals _{B b}
Ct
Cb
SGND
M icrocontroller
or DSC
BRUSHLESS
MOTOR
Control
Gate
A
Logic
Control
B
OUT A
OUT B
C
OUT C
SA306 Switching Amplifier
PGND (A&B)
SGND
Sensing
circuits
PGND (C)
GND
Sensor – Hall Sensors
or
Sensorless – Input from Stator leads

SA306U