This reference design demonstrates precise proportional solenoid drive using a simple push-pull output comparator and highly-accurate, integrated current shunt monitor. Precise and accurate control of proportional solenoids is especially necessary in the automatic transmission of a vehicle for smoother drivability. This design addresses two of the main factors that affect the precise position of a solenoid: drive and current-sense accuracy over temperature.
Features
- Current sense accuracy of 0.5% (FSR)
- Drive frequency and duty cycle: 1 kHz
- Integrated shunt facilitates more accuracy over a larger dynamic range
- Lower temperature drifts
- Wide common mode: –4 V to 80 V
- High-side drive, high-side solenoid monitor with enhanced PWM rejection