The LMD18245T is a Full-bridge Power Amplifier incorporates all the circuit blocks required to drive and control current in a brushed type DC motor or one phase of a bipolar stepper motor. The multi-technology process used to build the device combines bipolar and CMOS control and protection circuitry with DMOS power switches on the same monolithic structure. It controls the motor current via a fixed off-time chopper technique. An all DMOS H-bridge power stage delivers continuous output currents up to 3A (6A peak) at supply voltages up to 55V. The DMOS power switches feature low RDS (ON) for high efficiency and a diode intrinsic to the DMOS body structure eliminates the discrete diodes typically required to clamp bipolar power stages. An innovative current sensing method eliminates the power loss associated with a sense resistor in series with the motor. A four-bit digital-to-analogue converter (DAC) provides a digital path for controlling the motor current and by extension.
● DMOS power stage rated at 55V and 3A continuous
● Low RDS (ON) of typically 0.3R per power switch
● Internal clamp diodes
● Low-loss current sensing method
● Digital or analogue control of motor current
● TTL and CMOS compatible inputs
● Thermal shutdown (outputs off) at TJ = 155°C
● Overcurrent protection
● No shoot-through currents
● For higher resolution applications, an external DAC can be used
●Device has limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates.
