A3939 Three-Phase MOSFET Controller with Four-Quadrant Current Control
The A3939 is a three-phase, brushless, DC-motor controller for driving N-channel MOSFET motor drive bridges and is provided in the low profile 48-pin, LQFP package.
The high current gate drive capability allows driving of a wide range of power MOSFETs and can support motor supply voltages to 50V.
An LDO regulator supply is used for low-side drivers and charging bootstrap capacitors for high-side drivers.
Four-quadrant, current-controlled servos may use an analog voltage input for full-time control of average load current.
A user-selected, external timing capacitor and bias current resistor (and optional external sync input) control the waveform generator frequency used to modulate the motor terminals.
Two-quadrant control utilizes the same analog voltage input pin but sets only a maximum, absolute value on motor current. Current limiting (fast decay) is always available.
Main Features
- Operation over the full voltage range without circuit changes
- Latched (power loss) brake, soft brake
- Four quadrant current control
- Latched fault input/output
- Commutation logic for Hall sensors configured for 120-degree spacing
- Under Voltage Monitoring of supplies and bootcaps
- Thermal early warning and thermal shutdown
- Low profile (1mm body thickness) 48 lead TQFP package
Benefits derived from the unique features
- 50V output rating
- Four-quadrant average current control
Benefit: Improves current command accuracy for improved torque, speed and position control. - Drives Wide Range of N-channel MOSFETs
Benefit: Reduces problems from variations in MOSFET input capacitance (Device to device or manufacturer to manufacturer) - Adjustable Dead Time
Benefit: Improved cross-conduction protection - Selectable coast, brake, or soft brake on power-down, reset, fault or normal operation.
Benefit: Improved braking performance - Latched Fault Diagnostic Input/Output
Benefit: Mutiple motor drivers can respond uniformly to a fault in any one system - Thermal warning output and thermal shutdown
Benefit: Warning allows user to adjust driver performance before it effects system operation - 100% duty cycle
Benefit: No special control routines to keep MOSFET gates fully on or off - Special less than 12V ratings to cover supply variations
Benefit: Allows operation over normal 12V supply variations
Availability
Samples are available beginning September, preliminary datasheet is available upon request.